17-4 PH stainless steel 17-4 PH (UNS S17400, Type 630)
Fe balance, 15.0 to 17.5 Cr, 3.0 to 5.0 Ni, 3.0 to 5.0 Cu, 0.15 to 0.45 Nb plus Ta, max 0.070 C, max 1.00 Mn, max 1.00 Si, max 0.040 P, max 0.030 S (wt%)
Also known as UNS S17400, EN 1.4542, EN name X5CrNiCuNb16-4, AISI 630, JIS SUS630, AFNOR Z6CNU1704 · 16 more
17-4 PH is a martensitic, precipitation-hardening stainless steel with about 15 to 17.5 percent chromium, 3 to 5 percent nickel and 3 to 5 percent copper (Carpenter).
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Strength
1262 MPa
Stiffness
196 GPa
Hardness
36 HRC
Heat
316 °C
Recipe, share of the weight
- Fe balance (the rest)Iron
- Cr 15 to 17.5%Chromium
- Ni 3 to 5%Nickel
- Cu 3 to 5%Copper
- Nb+Ta 0.15 to 0.45%Niobium plus tantalum
- C 0 to 0.07%Carbon
- Mn 0 to 1%Manganese
- Si 0 to 1%Silicon
- P 0 to 0.04%Phosphorus
- S 0 to 0.03%Sulfur
Best for
High-strength fittings, fasteners, shafts and valve parts that need more strength than 304 and moderate corrosion resistance
Weakest at
Stress corrosion cracking and pitting in peak-aged (H900) material, and crevice corrosion in stagnant salt water
Risk at a glance
- People None found. No safety data sheet for the alloy was read
- If it fails High. Stress corrosion cracking at peak strength
- Corrosion Severe. Carpenter rates sea water as Restricted on its four-level comparative scale.
Quick facts: 17-4 PH (UNS S17400, Type 630)
| Property | Value | Basis |
|---|---|---|
| Density | 7.75 to 7.86 g/cm³ | 3 sourced values across conditions |
| Yield strength | 725 to 1,262 MPa | 9 sourced values across conditions |
| Tensile strength | 930 to 1,365 MPa | 9 sourced values across conditions |
| Young's modulus | 196 to 201 GPa | 2 sourced values across conditions |
| Thermal conductivity | 17.9 to 22.6 W/(m·K) | 2 sourced values across conditions |
| Thermal expansion (CTE) | 11.2 to 13 ppm/K | 4 sourced values across conditions |
| Melting point | 1,404 to 1,440 °C | 1 sourced value |
| Specific heat | 419 to 460 J/(kg·K) | 2 sourced values across conditions |
| Electrical resistivity | 7.7e-7 to 9.8e-7 Ω·m | 2 sourced values across conditions |
| Maximum service temperature | 316 °C | 1 sourced value |
What is the density of 17-4 PH stainless steel?
17-4 PH stainless steel has a density of 7.75 to 7.86 g/cm³. The range covers 3 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the thermal conductivity of 17-4 PH stainless steel?
17-4 PH stainless steel has a thermal conductivity of 17.9 to 22.6 W/(m·K). The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the coefficient of thermal expansion of 17-4 PH stainless steel?
17-4 PH stainless steel has a coefficient of thermal expansion of 11.2 to 13 ppm/K. The range covers 4 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the melting point of 17-4 PH stainless steel?
17-4 PH stainless steel has a melting point of 1,404 to 1,440 °C. The source and test conditions are listed in the properties table on this page.
What is the yield strength of 17-4 PH stainless steel?
17-4 PH stainless steel has a yield strength of 725 to 1,262 MPa. The range covers 9 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What are the other names and codes for 17-4 PH stainless steel?
17-4 PH stainless steel is also written as UNS S17400, EN 1.4542, EN name X5CrNiCuNb16-4, AISI 630, JIS SUS630, AFNOR Z6CNU1704. Each code is printed in the source listed beside it in the designations table.
What is 17-4 PH stainless steel used for?
Uses recorded in the sources include Aircraft and missile fittings; Bolts and fasteners; Jet engine stator vanes.
Why it exists
17-4 PH gives high strength from a simple one-step aging treatment, with corrosion resistance close to Type 304 in most media (Jacquet). Its weak point is that the highest strength comes with the greatest risk of stress corrosion cracking, so the aging condition is chosen for the environment as well as the load.
Where it's used
Aircraft and missile fittings
Carpenter lists aircraft and missile fittings for its 17-4 SELECT variant, and Steelforge lists forged aircraft fittings.
Bolts and fasteners
Austral Wright lists high-strength bolting and fasteners in aerospace and chemical plant use, and Jacquet lists AMS 7474 bolts.
Jet engine and pump parts
Ulbrich lists jet engine stator vanes, voestalpine lists pump shafts and rotors, and Steelforge lists valve parts and pump shafts.
Chemical, food and medical equipment
Ulbrich lists chemical, petrochemical and food processing equipment and surgical instruments, and Wikipedia lists medical devices and firearms.
Recipe
Fe balance, 15.0 to 17.5 Cr, 3.0 to 5.0 Ni, 3.0 to 5.0 Cu, 0.15 to 0.45 Nb plus Ta, max 0.070 C, max 1.00 Mn, max 1.00 Si, max 0.040 P, max 0.030 S (wt%)
17-4 PH is an iron-based martensitic precipitation-hardening stainless steel, UNS S17400 (AISI 630), made to the composition limits in the identity record with iron as the balance. It is supplied in the annealed condition, after a high-temperature solution treatment. One aging step at 480 to 620 C (900 to 1150 F) precipitates a copper-based phase that gives the strength (Austral Wright; Jacquet). Product forms are bar, sheet, plate, wire and forgings.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Iron Fe | balance (the rest) | Matrix of the alloy, martensitic when annealed. |
| Chromium Cr | 15 to 17.5% | Gives the passive film that resists rust; corrosion close to Type 304 in most media (Jacquet). |
| Nickel Ni | 3 to 5% | Part of the chromium-nickel-copper martensitic alloy (Carpenter: about 17 percent Cr and 4 percent Ni). |
| Copper Cu | 3 to 5% | Forms a copper-based phase on aging, which gives the high strength (Austral Wright). |
| Niobium plus tantalum Nb+Ta | 0.15 to 0.45% | Columbium plus tantalum, a listed alloying addition (Jacquet; Carpenter). |
| Carbon C | 0 to 0.07% | Kept low; Carpenter gives a maximum of 0.070 percent. |
| Manganese Mn | 0 to 1% | Residual element, maximum 1.00 percent. |
| Silicon Si | 0 to 1% | Residual element, maximum 1.00 percent. |
| Phosphorus P | 0 to 0.04% | Impurity held low, maximum 0.040 percent. |
| Sulfur S | 0 to 0.03% | Impurity held low, maximum 0.030 percent. |
Weight shares are as printed in the sources.
What it can do
Strength
1262 MPa
measured
Minimum yield is 1170 MPa in H900 and 725 MPa in H1150 for ASTM A564 bar (Austral Wright). Typical yield for cold-finished bar is 1262 MPa in H900 (Carpenter).
Stiffness
196 GPa
measured
Elastic modulus is 196 GPa in all conditions (Jacquet), and Austral Wright prints 200 to 201 GPa in tension.
Hardness
36 HRC
measured
Typical hardness is 44 HRC in H900 and 33 HRC in H1150 for cold-finished bar (Carpenter). Minimum hardness is 40 HRC in H900 (Austral Wright).
Heat
316 °C
measured
High strength is kept to about 316 C (600 F) (Jacquet).
How it compares
Jacquet says the corrosion resistance of 17-4 PH is comparable to Type 304 in most media and superior to the hardenable 400 series. Carpenter says its 17-4 SELECT variant approaches Type 304 in most corrodents and is better than the 400 series, while Carpenter's card calls the corrosion resistance moderate. Jacquet also says H900 gives the highest strength of this family, slightly below other precipitation-hardening grades that need more heat-treatment steps.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Other materials are shown beside it; each was measured under its own conditions, so open its page before comparing closely. Compare every grade in the family.
| Measurement | 17-4 PH (UNS S17400, Type 630) | 17-7 PH (UNS S17700, EN 1.4568, Type 631) | 15-7 PH |
|---|---|---|---|
| Capacity and energy | |||
| charpy impact energy | 20 J54 | no data | no data |
| charpy impact energy | 41 J55 | no data | no data |
| Thermal behavior and safety | |||
| melting point | 1404 °C8 | 1404 to 1440 °C | no data |
| Thermal conductivity | 17.9 W/m.K9 | 16.9 W/(m·K) | 16.2 W/m-K |
| Thermal conductivity | 22.6 W/m.K10 | 16.9 W/(m·K) | 16.2 W/m-K |
| specific heat | 419 J/kg.K11 | no data | no data |
| specific heat | 460 J/kg.K12 | no data | no data |
| Physical and electrical | |||
| Density | 7.75 g/cm³1 | 7.81 g/cm³ | 7.8 g/cm³ |
| Density | 7.81 g/cm³2 | 7.81 g/cm³ | 7.8 g/cm³ |
| Density | 7.86 g/cm³3 | 7.81 g/cm³ | 7.8 g/cm³ |
| electrical resistivity | 98 microhm-cm17 | 80 µΩ·cm | 82 microhm-cm |
| electrical resistivity | 77 microhm-cm18 | 80 µΩ·cm | 82 microhm-cm |
| hardness rockwell c | 36 HRC29 | no data | no data |
| hardness rockwell c | 44 HRC30 | no data | no data |
| hardness rockwell c | 38 HRC31 | no data | no data |
| hardness rockwell c | 33 HRC32 | no data | no data |
| hardness rockwell c | 40 HRC51 | no data | no data |
| hardness rockwell c | 35 HRC52 | no data | no data |
| hardness rockwell c | 28 HRC53 | no data | no data |
| Other measurements | |||
| elastic modulus | 196 GPa4 | 200 GPa | 28 10^6 psi |
| elastic modulus | 200 GPa5 | 200 GPa | 28 10^6 psi |
| shear modulus | 77.2 GPa6 | no data | no data |
| poissons ratio | 0.272 -7 | no data | no data |
| Thermal expansion (CTE) | 11.3 10-6/°C13 | 17.3 µm/(m·°C) | 14.4 10^-6/C |
| Thermal expansion (CTE) | 11.7 10-6/°C14 | 17.3 µm/(m·°C) | 14.4 10^-6/C |
| Thermal expansion (CTE) | 13 10-6/°C15 | 17.3 µm/(m·°C) | 14.4 10^-6/C |
| Thermal expansion (CTE) | 11.2 10-6/°C16 | 17.3 µm/(m·°C) | 14.4 10^-6/C |
| Maximum service temperature | 316 °C19 | no data | no data |
| yield strength | 1262 MPa20 | 310 MPa | 380 MPa |
| yield strength | 1117 MPa21 | 310 MPa | 380 MPa |
| yield strength | 869 MPa22 | 310 MPa | 380 MPa |
| ultimate tensile strength | 1365 MPa23 | 827 MPa | 860 MPa |
| ultimate tensile strength | 1158 MPa24 | 827 MPa | 860 MPa |
| ultimate tensile strength | 993 MPa25 | 827 MPa | 860 MPa |
| elongation | 15 %26 | 35 % | 30 % |
| elongation | 16 %27 | 35 % | 30 % |
| elongation | 20 %28 | 35 % | 30 % |
| yield strength | 760 MPa33 | 310 MPa | 380 MPa |
| yield strength | 1240 MPa34 | 310 MPa | 380 MPa |
| yield strength | 860 MPa35 | 310 MPa | 380 MPa |
| ultimate tensile strength | 1030 MPa36 | 827 MPa | 860 MPa |
| ultimate tensile strength | 1340 MPa37 | 827 MPa | 860 MPa |
| ultimate tensile strength | 1000 MPa38 | 827 MPa | 860 MPa |
| elongation | 8 %39 | 35 % | 30 % |
| elongation | 10 %40 | 35 % | 30 % |
| elongation | 10 %41 | 35 % | 30 % |
| yield strength | 1170 MPa42 | 310 MPa | 380 MPa |
| yield strength | 1000 MPa43 | 310 MPa | 380 MPa |
| yield strength | 725 MPa44 | 310 MPa | 380 MPa |
| ultimate tensile strength | 1310 MPa45 | 827 MPa | 860 MPa |
| ultimate tensile strength | 1070 MPa46 | 827 MPa | 860 MPa |
| ultimate tensile strength | 930 MPa47 | 827 MPa | 860 MPa |
| elongation | 10 %48 | 35 % | 30 % |
| elongation | 12 %49 | 35 % | 30 % |
| elongation | 16 %50 | 35 % | 30 % |
| elongation | 5 %56 | 35 % | 30 % |
| elongation | 5 %57 | 35 % | 30 % |
| elongation | 8 %58 | 35 % | 30 % |
Why choose it, and why not
Good for
- Fittings, fasteners and shafts where strength matters and exposure is mild, such as rural and mild industrial air (Austral Wright).
- Parts that can be aged to H1150 or double-aged for NACE sour service (voestalpine).
Watch out for
- Peak-aged H900 material is most prone to stress corrosion cracking. Age higher when chloride or sour service is possible (Jacquet; Carpenter).
- Crevice corrosion in stagnant salt water, and Restricted for sea water in Carpenter's table (Wikipedia; Carpenter).
- Annealed material is brittle and should not be used. Plasma torch cutting can crack it (Jacquet).
17-4 PH is the strong, moderately corrosion-resistant choice when a one-step age can set the strength. The aging condition is the design decision: H900 gives the most strength and the most stress corrosion risk, and H1150 gives more toughness and margin. For sea water or sour service, choose an overaged or NACE-listed condition and check the data for that condition.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Other names and standards
The same grade under other systems, as datasheets and standards print them. Each code was checked against the page it comes from.
| System | Codes |
|---|---|
| UNS | S17400 |
| EN | 1.4542 |
| EN name | X5CrNiCuNb16-4 |
| AISI | 630 |
| JIS | SUS630 |
| AFNOR | Z6CNU1704 |
| ASTM | A564 (bars, wire and shapes), A693 (sheet, plate and strip), A705 (forgings), F899 (when fully aged) |
| ASME | SA-564, SA-693 (plate, sheet and strip), SA-705 (forgings) |
| AMS | 5604 (sheet, strip and plate), 5643 (bars, forgings, tubing and rings), 5622, 5642 (bar), 5523, 7474 (bolts) |
| MIL | MIL-S-25043 |
| Trade name | Custom 630, 17-4 PH |
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Density | Physical properties table, Density in g/cm3 row, Condition A column | condition Condition A (annealed)basis typical, room temperatureform sheet, strip, plate and long products | — |
| 2 | Density | Physical properties table, Density in g/cm3 row, H 900 column | condition H900basis typical, room temperatureform sheet, strip, plate and long products | — |
| 3 | Density | Physical properties table, Density in g/cm3 row, H 1150 column | condition H1150basis typical, room temperatureform sheet, strip, plate and long products | — |
| 4 | elastic modulus | Mechanical properties table, Modulus of Elasticity row, GPa value in parentheses | condition all conditions printed (Condition A, H900, H1075, H1150)basis modulus of elasticity, printed as 28.5 x 10^6 psi (196 GPa) | — |
| 5 | elastic modulus | Physical properties table, Modulus of Elasticity tension row, minimum and maximum as printed | condition tension, printed as a range across conditionsbasis modulus of elasticity, tension | — |
| 6 | shear modulus | Mechanical properties table, Modulus of Rigidity row, GPa value in parentheses | condition all conditions printed (Condition A, H900, H1075, H1150)basis modulus of rigidity, printed as 11.2 x 10^6 psi (77.2 GPa) | — |
| 7 | poissons ratio | Physical properties table, Poisson's ratio rows, value as printed | condition H900, H1075 and H1150 (same value printed for each)basis room temperature | — |
| 8 | melting point | Physical properties table, Melting Range row, Celsius range as printed | basis melting range as printed, no solidus or liquidus splitunit in source 2560-2625 F (1404-1440 C) | — |
| 9 | Thermal conductivity | Physical properties table, Thermal Conductivity row, W/m.K value as printed | condition H900temperature 149 C (300 F)unit in source 124.0 Btu-in/hr/ft2/F at 300 F | — |
| 10 | Thermal conductivity | Physical properties table, Thermal Conductivity row, W/m.K value as printed | condition H900temperature 482 C (900 F)unit in source 157.0 Btu-in/hr/ft2/F at 900 F | — |
| 11 | specific heat | Physical properties table, Mean Specific Heat row, J/kg.K value as printed | condition not split by condition in the tabletemperature 0 to 100 C (32 to 212 F)unit in source 0.1000 Btu/lb/F | — |
| 12 | specific heat | Specific Heat (Annealed Condition) table, J/kg.K value as printed | condition Condition A (annealed)temperature 0 to 100 C (32 to 212 F)unit in source 0.11 Btu/lb/F | — |
| 13 | Thermal expansion (CTE) | Physical properties table, mean linear CTE at +70 to 800 F row, metric value in parentheses, Condition A column | condition Condition Atemperature 21 to 427 C (70 to 800 F) | — |
| 14 | Thermal expansion (CTE) | Physical properties table, mean linear CTE at +70 to 800 F row, metric value in parentheses, H 900 column | condition H900temperature 21 to 427 C (70 to 800 F) | — |
| 15 | Thermal expansion (CTE) | Physical properties table, mean linear CTE at +70 to 800 F row, metric value in parentheses, H 1150 column | condition H1150temperature 21 to 427 C (70 to 800 F) | — |
| 16 | Thermal expansion (CTE) | Mean Coefficient of Thermal Expansion table (annealed condition), value printed in μm/m·°C, which equals 10-6/°C | condition Condition A (annealed)temperature 21 to 427 C (70 to 800 F)unit in source μm/m·°C | — |
| 17 | electrical resistivity | Physical properties table, Electrical Resistivity row, value as printed | condition Condition A (annealed)temperature room temperature | — |
| 18 | electrical resistivity | Physical properties table, Electrical Resistivity row, value as printed | condition H900temperature room temperature | — |
| 19 | Maximum service temperature | Introduction text, Celsius value in parentheses as printed | basis statement that high strength is maintained to approximately 600 F (316 C) | — |
| 20 | yield strength | Typical mechanical properties table, 0.2 percent yield strength in MPa column | condition H900basis typical, room temperature, 0.2 percent offsetform bar, cold finished | — |
| 21 | yield strength | Typical mechanical properties table, 0.2 percent yield strength in MPa column | condition H1025basis typical, room temperature, 0.2 percent offsetform bar, cold finished | — |
| 22 | yield strength | Typical mechanical properties table, 0.2 percent yield strength in MPa column | condition H1150basis typical, room temperature, 0.2 percent offsetform bar, cold finished | — |
| 23 | ultimate tensile strength | Typical mechanical properties table, ultimate tensile strength in MPa column | condition H900basis typical, room temperatureform bar, cold finished | — |
| 24 | ultimate tensile strength | Typical mechanical properties table, ultimate tensile strength in MPa column | condition H1025basis typical, room temperatureform bar, cold finished | — |
| 25 | ultimate tensile strength | Typical mechanical properties table, ultimate tensile strength in MPa column | condition H1150basis typical, room temperatureform bar, cold finished | — |
| 26 | elongation | Typical mechanical properties table, elongation column | condition H900basis typical, elongation in 2 in (50.8 mm)form bar, cold finished | — |
| 27 | elongation | Typical mechanical properties table, elongation column | condition H1025basis typical, elongation in 2 in (50.8 mm)form bar, cold finished | — |
| 28 | elongation | Typical mechanical properties table, elongation column | condition H1150basis typical, elongation in 2 in (50.8 mm)form bar, cold finished | — |
| 29 | hardness rockwell c | Typical mechanical properties table, Rockwell C hardness column | condition Condition A (annealed and cold finished)basis typical, room temperature, Brinell 352 as printedform bar, cold finished | — |
| 30 | hardness rockwell c | Typical mechanical properties table, Rockwell C hardness column | condition H900basis typical, room temperature, Brinell 420 as printedform bar, cold finished | — |
| 31 | hardness rockwell c | Typical mechanical properties table, Rockwell C hardness column | condition H1025basis typical, room temperature, Brinell 352 as printedform bar, cold finished | — |
| 32 | hardness rockwell c | Typical mechanical properties table, Rockwell C hardness column | condition H1150basis typical, room temperature, Brinell 311 as printedform bar, cold finished | — |
| 33 | yield strength | Mechanical properties table, 0.2 percent offset yield strength in MPa row | condition Condition Abasis typical, room temperature, 0.2 percent offsetform sheet, strip, plate and long products | — |
| 34 | yield strength | Mechanical properties table, 0.2 percent offset yield strength in MPa row | condition H900basis typical, room temperature, 0.2 percent offsetform sheet, strip, plate and long products | — |
| 35 | yield strength | Mechanical properties table, 0.2 percent offset yield strength in MPa row | condition H1150basis typical, room temperature, 0.2 percent offsetform sheet, strip, plate and long products | — |
| 36 | ultimate tensile strength | Mechanical properties table, Ultimate Tensile Strength in MPa row | condition Condition Abasis typical, room temperatureform sheet, strip, plate and long products | — |
| 37 | ultimate tensile strength | Mechanical properties table, Ultimate Tensile Strength in MPa row | condition H900basis typical, room temperatureform sheet, strip, plate and long products | — |
| 38 | ultimate tensile strength | Mechanical properties table, Ultimate Tensile Strength in MPa row | condition H1150basis typical, room temperatureform sheet, strip, plate and long products | — |
| 39 | elongation | Mechanical properties table, Elongation row, percentage in 2 in | condition Condition Abasis typical, elongation in 2 inform sheet, strip, plate and long products | — |
| 40 | elongation | Mechanical properties table, Elongation row, percentage in 2 in | condition H900basis typical, elongation in 2 inform sheet, strip, plate and long products | — |
| 41 | elongation | Mechanical properties table, Elongation row, percentage in 2 in | condition H1150basis typical, elongation in 2 inform sheet, strip, plate and long products | — |
| 42 | yield strength | Minimum properties table, 0.2 percent proof stress MPa (min) column | condition H900basis minimum, ASTM A564 bar tableheat treatment 480 C, 1 h, air coolform bar and shapes | — |
| 43 | yield strength | Minimum properties table, 0.2 percent proof stress MPa (min) column | condition H1025basis minimum, ASTM A564 bar tableheat treatment 550 C, 4 h, air coolform bar and shapes | — |
| 44 | yield strength | Minimum properties table, 0.2 percent proof stress MPa (min) column | condition H1150basis minimum, ASTM A564 bar tableheat treatment 620 C, 4 h, air coolform bar and shapes | — |
| 45 | ultimate tensile strength | Minimum properties table, tensile strength MPa (min) column | condition H900basis minimum, ASTM A564 bar tableheat treatment 480 C, 1 h, air coolform bar and shapes | — |
| 46 | ultimate tensile strength | Minimum properties table, tensile strength MPa (min) column | condition H1025basis minimum, ASTM A564 bar tableheat treatment 550 C, 4 h, air coolform bar and shapes | — |
| 47 | ultimate tensile strength | Minimum properties table, tensile strength MPa (min) column | condition H1150basis minimum, ASTM A564 bar tableheat treatment 620 C, 4 h, air coolform bar and shapes | — |
| 48 | elongation | Minimum properties table, elongation percent (min) column | condition H900basis minimum, ASTM A564 bar tableform bar and shapes | — |
| 49 | elongation | Minimum properties table, elongation percent (min) column | condition H1025basis minimum, ASTM A564 bar tableform bar and shapes | — |
| 50 | elongation | Minimum properties table, elongation percent (min) column | condition H1150basis minimum, ASTM A564 bar tableform bar and shapes | — |
| 51 | hardness rockwell c | Minimum properties table, Hardness Rockwell C (min) column | condition H900basis minimum, ASTM A564 bar tableform bar and shapes | — |
| 52 | hardness rockwell c | Minimum properties table, Hardness Rockwell C (min) column | condition H1025basis minimum, ASTM A564 bar tableform bar and shapes | — |
| 53 | hardness rockwell c | Minimum properties table, Hardness Rockwell C (min) column | condition H1150basis minimum, ASTM A564 bar tableform bar and shapes | — |
| 54 | charpy impact energy | Minimum properties table, Impact Charpy VJ (min) column | condition H1025basis minimum, ASTM A564 bar table, Charpy V-notchform bar and shapes | — |
| 55 | charpy impact energy | Minimum properties table, Impact Charpy VJ (min) column | condition H1150basis minimum, ASTM A564 bar table, Charpy V-notchform bar and shapes | — |
| 56 | elongation | Heat treat capabilities (aged) table, elongation min | condition H900basis minimum, wire datasheetform wire | — |
| 57 | elongation | Heat treat capabilities (aged) table, elongation min | condition H1025basis minimum, wire datasheetform wire | — |
| 58 | elongation | Heat treat capabilities (aged) table, elongation min | condition H1150basis minimum, wire datasheetform wire | — |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Sea water | severe | Carpenter rates sea water as Restricted on its four-level comparative scale.1 |
| Salt spray (NaCl) | low | Carpenter rates salt spray as Good.2 |
| Humidity | low | Carpenter rates humidity as Excellent.3 |
| Nitric acid | low | Carpenter rates nitric acid as Good.4 |
| Sulfuric acid | severe | Carpenter rates sulfuric acid as Restricted.5 |
| Sour oil and gas | severe | Carpenter rates sour oil and gas as Restricted.6 |
| Sea coast atmosphere and salt water service | not rated | Sea coast air causes slow light rusting and pitting; salt water use relies on cathodic protection.7 |
| Crevice corrosion in stagnant salt water | not rated | Crevice corrosion can occur in stagnant salt water.8 |
| General corrosion in most media | low | Corrosion resistance is comparable to Type 304 in most media and superior to the 400 series.9 |
| Peak-aged material in chloride service | not rated | Peak-aged material is more susceptible to stress corrosion cracking.10 |
| Hardening temperature and stress corrosion cracking | not rated | Good stress corrosion resistance comes from hardening at 1025 F (552 C) or higher.11 |
| Overaged condition and stress corrosion cracking | not rated | Overaging improves resistance to stress corrosion cracking.12 |
| Annealed (untempered martensite) material | not rated | Annealed material is more sensitive to hydrogen embrittlement and chloride cracking than aged material.13 |
| Sour (NACE) service | not rated | H1150M and DH1150 are stocked for NACE service.14 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Sea water | On Carpenter's comparative scale (Excellent, Good, Moderate, Restricted) sea water is Restricted for 17-4 SELECT, which carries the same UNS S17400 type. The scale is for comparison only and says corrosion testing is recommended. The site rating is mapped as Restricted to severe. | medium sea waterscale Carpenter comparative rating |
| 2 | Salt spray (NaCl) | On Carpenter's comparative scale the salt spray entry for 17-4 SELECT is Good, mapped here to low. | medium salt spray (NaCl)scale Carpenter comparative rating |
| 3 | Humidity | On Carpenter's comparative scale the humidity entry for 17-4 SELECT is Excellent, mapped here to low. | medium humid airscale Carpenter comparative rating |
| 4 | Nitric acid | Carpenter's comparative table gives 17-4 SELECT a Good rating in nitric acid, mapped here to low. The table says factors such as temperature, concentration and pH change the result. | medium nitric acidscale Carpenter comparative rating |
| 5 | Sulfuric acid | Carpenter's comparative table gives 17-4 SELECT a Restricted rating in sulfuric acid, mapped here to severe. | medium sulfuric acidscale Carpenter comparative rating |
| 6 | Sour oil and gas | Carpenter's comparative table rates sour oil and gas as Restricted for 17-4 SELECT, mapped here to severe. Use the NACE-listed aged conditions for sour service (see the mitigations). | medium sour oil and gasscale Carpenter comparative rating |
| 7 | Sea coast atmosphere and salt water service | Austral Wright says 17-4PH develops overall light rusting and pitting slowly in sea coast atmospheres, and that it is used successfully in salt water as boat shafting with cathodic protection. | medium sea coast atmosphere; salt water with cathodic protection |
| 8 | Crevice corrosion in stagnant salt water | Wikipedia says 17-4 is susceptible to crevice corrosion in stagnant salt water, and that its corrosion resistance and machinability are comparable to 304. | medium stagnant salt water in crevices |
| 9 | General corrosion in most media | Jacquet states that corrosion resistance is comparable to Type 304 stainless steel in most media and superior to the hardenable 400 series stainless steels. Carpenter's card describes the corrosion resistance as moderate. | medium most media |
| 10 | Peak-aged material in chloride service | Jacquet says 17-4 is more susceptible to stress corrosion cracking at peak strength. Where chloride stress corrosion cracking is possible, the alloy should be precipitation hardened to the lowest hardness compatible with the use, by heat treating at the highest temperature that still gives the minimum properties. | condition H900 and other peak-aged conditionsmedium chloride |
| 11 | Hardening temperature and stress corrosion cracking | Carpenter says good resistance to stress corrosion cracking is gained by hardening at 1025 F (552 C) and higher, and that 17-4 SELECT withstood corrosive attack better than the 400 series hardenable stainless steels. | temperature 1025 F (552 C) and higher for aging |
| 12 | Overaged condition and stress corrosion cracking | Wikipedia says overaging, meaning aging beyond the peak strength condition, improves resistance to stress corrosion cracking. | condition overaged (beyond peak strength) |
| 13 | Annealed (untempered martensite) material | Jacquet says annealed 17-4 has untempered martensite, which may fail by unpredictable brittle fracture and is more sensitive to hydrogen embrittlement and chloride stress corrosion cracking than aged material. | condition Condition A (annealed) |
| 14 | Sour (NACE) service | voestalpine says it stocks several conditions of 17-4, including H1150M and DH1150, for NACE service. The page gives no crack threshold data. | condition H1150M and DH1150 (double-aged) |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
The PubChem records below cover elemental nickel, chromium and copper, not the finished 17-4 PH alloy.
- Nickel
- PubChem lists elemental nickel as Danger, with H317 (skin sensitiser), H351 (suspected carcinogen) and H372 (organ damage on repeated exposure).
- Chromium
- PubChem lists elemental chromium as Danger with H317, H319 and H334 in notifications that carry hazard codes.
- Copper
- PubChem lists elemental copper as Warning, with H400 and H410 for aquatic life.
- Workshop
- Check the supplier safety data sheet before cutting, grinding or welding this alloy.
In the environment
Crevice corrosion and stress corrosion cracking are the main failure routes in service.
- Sea water
- Carpenter rates sea water as Restricted for 17-4 SELECT. Austral Wright uses it in salt water as boat shafting only with cathodic protection.
- Crevices
- Wikipedia says it is susceptible to crevice corrosion in stagnant salt water.
- Sour service
- Carpenter rates sour oil and gas as Restricted. voestalpine stocks H1150M and DH1150 for NACE service.
Heat treatment and fabrication
The highest strength comes from the H900 condition, which is also the most prone to stress corrosion cracking.
- Peak aging
- Jacquet says 17-4 is more susceptible to stress corrosion cracking at peak strength, so the lowest hardness compatible with the use is preferred.
- Annealed
- Untempered martensite in the annealed condition may fail unpredictably and is more sensitive to hydrogen embrittlement (Jacquet).
- Torch cutting
- Plasma torch cutting of annealed plate can crack the metal, especially plate thicker than about 1 inch (Jacquet).
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Stress corrosion cracking at peak strengthhigh severity | Chloride or other corrosive exposure with H900 or other peak-aged material under tensile stressBrittle cracking in service; Jacquet says to age to the lowest hardness compatible with the use |
| Brittle fracture of material left in the annealed conditionhigh severity | Service or fabrication in Condition A (annealed) without an aging treatmentUntempered martensite may fail unpredictably and is more sensitive to hydrogen embrittlement and chloride cracking |
| Crevice and pitting corrosion in salt watermoderate severity | Stagnant salt water, crevices, or sea coast atmosphereCrevice corrosion in stagnant salt water; slow light rusting and pitting in sea coast air |
| Cracking during plasma torch cuttingmoderate severity | Plasma torch cutting of material in the as-annealed condition, especially plate thicker than about 1 inch (25.4 mm)Cracks that may propagate far into the base metal |
| Loss of strength from overagingmoderate severity | Aging above the specified temperature or for too longThe precipitation reaction passes peak strength, so strength and hardness fall |
Handling and storage
- Do not put annealed (Condition A) material into service; age it to a specified H condition first.
- Choose the aging temperature for stress corrosion as well as strength. Hardening at 1025 F (552 C) or higher gives good stress corrosion resistance.
- Severe cold working should be done in the H1150 condition, and the part should be re-aged after cold forming.
- Multipass welds must be solution annealed before aging; single-pass welds are precipitation hardened after welding.
- Oxyacetylene welding is not recommended because carbon pick-up can occur in the weld; use a 17-4PH type filler.
- Before plasma torch cutting, age the material at 1150 F (621 C) or higher to lower the cracking risk, then re-solution anneal and re-age after machining.
- Avoid protective atmospheres containing carbon or nitrogen during heat treatment; they can soften the surface.
Mitigations
- For NACE sour service, use the H1150M or double-aged DH1150 conditions, which voestalpine stocks for that service.
- Clean and passivate after fabrication, and remove scale, lubricants and drawing coatings, which Carpenter says matter for corrosion resistance.
- Overaging, meaning aging beyond the peak strength condition, improves resistance to stress corrosion cracking.
Supply and geography
How common the raw materials are and where they come from.
Nickel production by country (world mine, 2025 estimate)
World mine production 3,900,000 t in 2025 (estimated); world reserves more than 140,000,000 t, of which Indonesia 62,000,000 t (USGS 2026).
- Top producers (2025)
- Indonesia 66.7%, Philippines 6.9%, Russia 5.1%, New Caledonia 3.6%, Canada 3.6%, China 3.1%
- Recycling
- Nickel recovered from scrap accounted for about 60% of US apparent consumption in 2025; most secondary nickel is stainless-steel scrap.
- Substitutes
- Low-nickel, duplex or ultrahigh-chromium stainless steels replace austenitic grades in construction; Titanium alloys can substitute for nickel or nickel-base alloys in corrosive environments
Nickel use in the United States
Stainless and alloy steel and nickel-containing alloys typically account for more than 85% of domestic consumption. US net import reliance 41% of apparent consumption in 2025 (estimated).
- Recycling
- Recycled nickel 60% of US apparent consumption in 2025.
Chromium production by country (world mine, 2025 estimate)
World mine production 51,000 thousand t gross weight in 2025 (estimated); world resources greater than 12 billion t of shipping-grade chromite, with 95% of chromium resources in Kazakhstan and southern Africa.
- Top producers (2025)
- South Africa 45.1%, Turkey 17.6%, Kazakhstan 13.7%, India 5.9%, Brazil 3.9%, Zimbabwe 3.9%
- Recycling
- Recycled chromium in stainless-steel scrap receipts was 21% of US apparent consumption in 2025.
- Substitutes
- Chromium has no substitute in stainless steel, the leading end use
Chromium import reliance
US net import reliance 79% of apparent consumption in 2025 (estimated).
Copper production by country (world mine, 2025 estimate)
World mine production 23,000 thousand t in 2025 (estimated); world reserves 980,000 thousand t (USGS 2026).
- Top producers (2025)
- Chile 23%, Congo (Kinshasa) 13.9%, Peru 11.7%, China 7.8%, Russia 5.7%
- Critical mineral lists
- U.S. Final 2025 List of Critical Minerals (Federal Register, 7 November 2025): listed
- Recycling
- Old scrap converted to refined metal provided about 160,000 t of copper in 2025, and copper from scrap contributed about 30% of US supply.
- Substitutes
- Aluminum substitutes for copper in electrical equipment and power cable; titanium and steel are used in heat exchangers
Copper use and import reliance in the United States
US net import reliance 57% of apparent consumption in 2025 (estimated). Building construction takes 42% of copper and copper alloy products, electrical and electronic products 23%.
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
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spore: profile
id: stainless-17-4ph
spore_version: 0.2
family: stainless-precipitation-hardening
name: 17-4 PH stainless steel
abbreviation: 17-4 PH (UNS S17400, Type 630)
role: precipitation-hardening structural alloy
category: metals
type: steels-and-stainless
summary: |
17-4 PH is a martensitic, precipitation-hardening stainless steel with about 15 to 17.5 percent chromium, 3 to 5 percent nickel and 3 to 5 percent copper (Carpenter). It is supplied annealed and then aged in one step at about 480 to 620 C (900 to 1150 F). The aging temperature sets the strength: H900 is the strongest and hardest condition, and H1150 is softer and tougher. In most media its corrosion resistance is close to Type 304, but peak-aged material is more prone to stress corrosion cracking, so the aging condition has to be chosen for the environment as well as the load.
best_for: High-strength fittings, fasteners, shafts and valve parts that need more strength than 304 and moderate corrosion resistance
weakest_at: Stress corrosion cracking and pitting in peak-aged (H900) material, and crevice corrosion in stagnant salt water
identity:
formula: Fe balance, 15.0 to 17.5 Cr, 3.0 to 5.0 Ni, 3.0 to 5.0 Cu, 0.15 to 0.45 Nb plus Ta, max 0.070 C, max 1.00 Mn, max 1.00 Si, max 0.040 P, max 0.030 S (wt%)
source: carp-select
where: Type analysis table (Carpenter 17-4 SELECT data sheet, UNS S17400 type)
designations:
- system: UNS
code: S17400
source: carp-select
where: 'Associated identifiers line: UNS S17400'
- system: AISI
code: '630'
source: carp-select
where: 'Associated identifiers line: AISI 630'
- system: EN
code: '1.4542'
source: austral-174
where: 'Equivalent Specifications table, Steel Europe row: EN10088 X5CrNiCuNb16-4 1.4542'
- system: EN name
code: X5CrNiCuNb16-4
source: austral-174
where: Equivalent Specifications table, Steel Europe row
- system: JIS
code: SUS630
source: austral-174
where: 'Equivalent Specifications table, Japan row: JIS G4305 SUS 630'
- system: AFNOR
code: Z6CNU1704
source: ams5643-page
where: 'Specifications list: AFNOR Z6CNU1704, beside WS 1.4542'
- system: ASTM
code: A564
note: bars, wire and shapes
source: jacquet-174
where: 'Specifications table: ASTM A564 Bars, Wire and Shapes'
- system: ASTM
code: A693
note: sheet, plate and strip
source: jacquet-174
where: 'Specifications table: ASTM A693 Sheet, Plate and Strip'
- system: ASTM
code: A705
note: forgings
source: jacquet-174
where: 'Specifications table: ASTM A705 Forgings'
- system: ASTM
code: F899
note: when fully aged
source: carp-select
where: 'Applicable specifications line: ASTM F899 (when fully aged)'
- system: ASME
code: SA-564
source: carp-select
where: 'Applicable specifications line: ASME SA564'
- system: ASME
code: SA-693
note: plate, sheet and strip
source: jacquet-174
where: 'Specifications table: ASME SA-693 beside ASTM A693'
- system: ASME
code: SA-705
note: forgings
source: jacquet-174
where: 'Specifications table: ASME SA-705 beside ASTM A705'
- system: AMS
code: '5604'
note: sheet, strip and plate
source: jacquet-174
where: 'Specifications table: AMS 5604 Sheet, Strip and Plate'
- system: AMS
code: '5643'
note: bars, forgings, tubing and rings
source: jacquet-174
where: 'Specifications table: AMS 5643 Bars, Forgings, Tubing and Rings'
- system: AMS
code: '5622'
note: vacuum melt; bars, wire, forgings, tubing and rings
source: ams5643-page
where: 'Specifications list: AMS 5622 (Vac Melt) Bars, Wire, Forgings, Tubing and Rings'
- system: AMS
code: '5642'
note: bar
source: ams5643-page
where: 'Specifications list: AMS 5642 Bar'
- system: AMS
code: '5523'
source: ulbrich-wire
where: 'Product heading: ASTM A564, ASTM 693, AMS 5523, AMS 5604, AMS 5643'
- system: AMS
code: '7474'
note: bolts
source: jacquet-174
where: 'Specifications table: AMS 7474 Bolts'
- system: MIL
code: MIL-S-25043
source: ams5643-page
where: 'Specifications list: MIL-S-25043'
- system: Trade name
code: Custom 630
source: carp-card
where: 'Card title: Custom 630 (17-4)'
- system: Trade name
code: 17-4 PH
source: ulbrich-wire
where: 'Title: 17-4 PH® Stainless Steel, UNS S17400'
tags:
environments: []
stresses: []
applications:
- structures
- mechanisms
- propulsion-and-tanks
properties:
- benchmark: density
value: 7.75
unit: g/cm3
scope: material
conditions:
condition: Condition A (annealed)
basis: typical, room temperature
form: sheet, strip, plate and long products
method: Physical properties table, Density in g/cm3 row, Condition A column
status: ground
source: jacquet-174
where: Physical properties table (Density, g/cm3 row)
- benchmark: density
value: 7.81
unit: g/cm3
scope: material
conditions:
condition: H900
basis: typical, room temperature
form: sheet, strip, plate and long products
method: Physical properties table, Density in g/cm3 row, H 900 column
status: ground
source: jacquet-174
where: Physical properties table (Density, g/cm3 row)
- benchmark: density
value: 7.86
unit: g/cm3
scope: material
conditions:
condition: H1150
basis: typical, room temperature
form: sheet, strip, plate and long products
method: Physical properties table, Density in g/cm3 row, H 1150 column
status: ground
source: jacquet-174
where: Physical properties table (Density, g/cm3 row)
- benchmark: elastic_modulus
value: 196
unit: GPa
scope: material
conditions:
condition: all conditions printed (Condition A, H900, H1075, H1150)
basis: modulus of elasticity, printed as 28.5 x 10^6 psi (196 GPa)
method: Mechanical properties table, Modulus of Elasticity row, GPa value in parentheses
status: ground
source: jacquet-174
where: Mechanical properties table (Modulus of Elasticity row)
- benchmark: elastic_modulus
value: 200
value_high: 201
unit: GPa
scope: material
conditions:
condition: tension, printed as a range across conditions
basis: modulus of elasticity, tension
method: Physical properties table, Modulus of Elasticity tension row, minimum and maximum as printed
status: ground
source: austral-174
where: Physical Properties table (Modulus of Elasticity, Tension row)
- benchmark: shear_modulus
value: 77.2
unit: GPa
scope: material
conditions:
condition: all conditions printed (Condition A, H900, H1075, H1150)
basis: modulus of rigidity, printed as 11.2 x 10^6 psi (77.2 GPa)
method: Mechanical properties table, Modulus of Rigidity row, GPa value in parentheses
status: ground
source: jacquet-174
where: Mechanical properties table (Modulus of Rigidity row)
- benchmark: poissons_ratio
value: 0.272
unit: '-'
scope: material
conditions:
condition: H900, H1075 and H1150 (same value printed for each)
basis: room temperature
method: Physical properties table, Poisson's ratio rows, value as printed
status: ground
source: carp-select
where: Physical properties table (Poisson's ratio, three condition rows)
- benchmark: melting_point
value: 1404
value_high: 1440
unit: °C
scope: material
conditions:
basis: melting range as printed, no solidus or liquidus split
unit_in_source: 2560-2625 F (1404-1440 C)
method: Physical properties table, Melting Range row, Celsius range as printed
status: ground
source: upmet-174
where: Physical Properties table (Melting Range row)
- benchmark: thermal_conductivity
value: 17.9
unit: W/m.K
scope: material
conditions:
condition: H900
temperature: 149 C (300 F)
unit_in_source: 124.0 Btu-in/hr/ft2/F at 300 F
method: Physical properties table, Thermal Conductivity row, W/m.K value as printed
status: ground
source: carp-select
where: Physical properties, Thermal Conductivity, H 900 at 300 F (149 C)
- benchmark: thermal_conductivity
value: 22.6
unit: W/m.K
scope: material
conditions:
condition: H900
temperature: 482 C (900 F)
unit_in_source: 157.0 Btu-in/hr/ft2/F at 900 F
method: Physical properties table, Thermal Conductivity row, W/m.K value as printed
status: ground
source: carp-select
where: Physical properties, Thermal Conductivity, H 900 at 900 F (482 C)
- benchmark: specific_heat
value: 419
unit: J/kg.K
scope: material
conditions:
condition: not split by condition in the table
temperature: 0 to 100 C (32 to 212 F)
unit_in_source: 0.1000 Btu/lb/F
method: Physical properties table, Mean Specific Heat row, J/kg.K value as printed
status: ground
source: carp-select
where: Physical properties table (Mean Specific Heat row)
- benchmark: specific_heat
value: 460
unit: J/kg.K
scope: material
conditions:
condition: Condition A (annealed)
temperature: 0 to 100 C (32 to 212 F)
unit_in_source: 0.11 Btu/lb/F
method: Specific Heat (Annealed Condition) table, J/kg.K value as printed
status: ground
source: upmet-174
where: Physical Properties table (Specific Heat, annealed condition row)
- benchmark: cte
value: 11.3
unit: 10-6/°C
scope: material
conditions:
condition: Condition A
temperature: 21 to 427 C (70 to 800 F)
method: Physical properties table, mean linear CTE at +70 to 800 F row, metric value in parentheses, Condition A column
status: ground
source: jacquet-174
where: Physical properties table (Linear Coefficient of Thermal Expansion, +70 to 800 F row)
- benchmark: cte
value: 11.7
unit: 10-6/°C
scope: material
conditions:
condition: H900
temperature: 21 to 427 C (70 to 800 F)
method: Physical properties table, mean linear CTE at +70 to 800 F row, metric value in parentheses, H 900 column
status: ground
source: jacquet-174
where: Physical properties table (Linear Coefficient of Thermal Expansion, +70 to 800 F row)
- benchmark: cte
value: 13
unit: 10-6/°C
scope: material
conditions:
condition: H1150
temperature: 21 to 427 C (70 to 800 F)
method: Physical properties table, mean linear CTE at +70 to 800 F row, metric value in parentheses, H 1150 column
status: ground
source: jacquet-174
where: Physical properties table (Linear Coefficient of Thermal Expansion, +70 to 800 F row)
- benchmark: cte
value: 11.2
unit: 10-6/°C
scope: material
conditions:
condition: Condition A (annealed)
temperature: 21 to 427 C (70 to 800 F)
unit_in_source: μm/m·°C
method: Mean Coefficient of Thermal Expansion table (annealed condition), value printed in μm/m·°C, which equals 10-6/°C
status: ground
source: upmet-174
where: Physical properties table (Mean Coefficient of Thermal Expansion, 21-427 C row)
- benchmark: electrical_resistivity
value: 98
unit: microhm-cm
scope: material
conditions:
condition: Condition A (annealed)
temperature: room temperature
method: Physical properties table, Electrical Resistivity row, value as printed
status: ground
source: jacquet-174
where: Physical properties table (Electrical Resistivity row, Condition A column)
- benchmark: electrical_resistivity
value: 77
unit: microhm-cm
scope: material
conditions:
condition: H900
temperature: room temperature
method: Physical properties table, Electrical Resistivity row, value as printed
status: ground
source: jacquet-174
where: Physical properties table (Electrical Resistivity row, H 900 column)
- benchmark: max_service_temp
value: 316
unit: °C
scope: material
conditions:
basis: statement that high strength is maintained to approximately 600 F (316 C)
method: Introduction text, Celsius value in parentheses as printed
status: ground
source: jacquet-174
where: Introduction (high strength maintained to approximately 600 F (316 C))
- benchmark: yield_strength
value: 1262
unit: MPa
scope: material
conditions:
condition: H900
basis: typical, room temperature, 0.2 percent offset
form: bar, cold finished
method: Typical mechanical properties table, 0.2 percent yield strength in MPa column
status: ground
source: carp-select
where: Typical mechanical properties table (H 900 row, MPa)
- benchmark: yield_strength
value: 1117
unit: MPa
scope: material
conditions:
condition: H1025
basis: typical, room temperature, 0.2 percent offset
form: bar, cold finished
method: Typical mechanical properties table, 0.2 percent yield strength in MPa column
status: ground
source: carp-select
where: Typical mechanical properties table (H 1025 row, MPa)
- benchmark: yield_strength
value: 869
unit: MPa
scope: material
conditions:
condition: H1150
basis: typical, room temperature, 0.2 percent offset
form: bar, cold finished
method: Typical mechanical properties table, 0.2 percent yield strength in MPa column
status: ground
source: carp-select
where: Typical mechanical properties table (H 1150 row, MPa)
- benchmark: ultimate_tensile_strength
value: 1365
unit: MPa
scope: material
conditions:
condition: H900
basis: typical, room temperature
form: bar, cold finished
method: Typical mechanical properties table, ultimate tensile strength in MPa column
status: ground
source: carp-select
where: Typical mechanical properties table (H 900 row, MPa)
- benchmark: ultimate_tensile_strength
value: 1158
unit: MPa
scope: material
conditions:
condition: H1025
basis: typical, room temperature
form: bar, cold finished
method: Typical mechanical properties table, ultimate tensile strength in MPa column
status: ground
source: carp-select
where: Typical mechanical properties table (H 1025 row, MPa)
- benchmark: ultimate_tensile_strength
value: 993
unit: MPa
scope: material
conditions:
condition: H1150
basis: typical, room temperature
form: bar, cold finished
method: Typical mechanical properties table, ultimate tensile strength in MPa column
status: ground
source: carp-select
where: Typical mechanical properties table (H 1150 row, MPa)
- benchmark: elongation
value: 15
unit: '%'
scope: material
conditions:
condition: H900
basis: typical, elongation in 2 in (50.8 mm)
form: bar, cold finished
method: Typical mechanical properties table, elongation column
status: ground
source: carp-select
where: Typical mechanical properties table (H 900 row, elongation)
- benchmark: elongation
value: 16
unit: '%'
scope: material
conditions:
condition: H1025
basis: typical, elongation in 2 in (50.8 mm)
form: bar, cold finished
method: Typical mechanical properties table, elongation column
status: ground
source: carp-select
where: Typical mechanical properties table (H 1025 row, elongation)
- benchmark: elongation
value: 20
unit: '%'
scope: material
conditions:
condition: H1150
basis: typical, elongation in 2 in (50.8 mm)
form: bar, cold finished
method: Typical mechanical properties table, elongation column
status: ground
source: carp-select
where: Typical mechanical properties table (H 1150 row, elongation)
- benchmark: hardness_rockwell_c
value: 36
unit: HRC
scope: material
conditions:
condition: Condition A (annealed and cold finished)
basis: typical, room temperature, Brinell 352 as printed
form: bar, cold finished
method: Typical mechanical properties table, Rockwell C hardness column
status: ground
source: carp-select
where: Typical mechanical properties table (Hardness, Condition A row)
- benchmark: hardness_rockwell_c
value: 44
unit: HRC
scope: material
conditions:
condition: H900
basis: typical, room temperature, Brinell 420 as printed
form: bar, cold finished
method: Typical mechanical properties table, Rockwell C hardness column
status: ground
source: carp-select
where: Typical mechanical properties table (Hardness, H 900 row)
- benchmark: hardness_rockwell_c
value: 38
unit: HRC
scope: material
conditions:
condition: H1025
basis: typical, room temperature, Brinell 352 as printed
form: bar, cold finished
method: Typical mechanical properties table, Rockwell C hardness column
status: ground
source: carp-select
where: Typical mechanical properties table (Hardness, H 1025 row)
- benchmark: hardness_rockwell_c
value: 33
unit: HRC
scope: material
conditions:
condition: H1150
basis: typical, room temperature, Brinell 311 as printed
form: bar, cold finished
method: Typical mechanical properties table, Rockwell C hardness column
status: ground
source: carp-select
where: Typical mechanical properties table (Hardness, H 1150 row)
- benchmark: yield_strength
value: 760
unit: MPa
scope: material
conditions:
condition: Condition A
basis: typical, room temperature, 0.2 percent offset
form: sheet, strip, plate and long products
method: Mechanical properties table, 0.2 percent offset yield strength in MPa row
status: ground
source: jacquet-174
where: Mechanical properties table (0.2 percent Offset Yield Strength, MPa, Condition A)
- benchmark: yield_strength
value: 1240
unit: MPa
scope: material
conditions:
condition: H900
basis: typical, room temperature, 0.2 percent offset
form: sheet, strip, plate and long products
method: Mechanical properties table, 0.2 percent offset yield strength in MPa row
status: ground
source: jacquet-174
where: Mechanical properties table (0.2 percent Offset Yield Strength, MPa, H 900)
- benchmark: yield_strength
value: 860
unit: MPa
scope: material
conditions:
condition: H1150
basis: typical, room temperature, 0.2 percent offset
form: sheet, strip, plate and long products
method: Mechanical properties table, 0.2 percent offset yield strength in MPa row
status: ground
source: jacquet-174
where: Mechanical properties table (0.2 percent Offset Yield Strength, MPa, H 1150)
- benchmark: ultimate_tensile_strength
value: 1030
unit: MPa
scope: material
conditions:
condition: Condition A
basis: typical, room temperature
form: sheet, strip, plate and long products
method: Mechanical properties table, Ultimate Tensile Strength in MPa row
status: ground
source: jacquet-174
where: Mechanical properties table (Ultimate Tensile Strength, MPa, Condition A)
- benchmark: ultimate_tensile_strength
value: 1340
unit: MPa
scope: material
conditions:
condition: H900
basis: typical, room temperature
form: sheet, strip, plate and long products
method: Mechanical properties table, Ultimate Tensile Strength in MPa row
status: ground
source: jacquet-174
where: Mechanical properties table (Ultimate Tensile Strength, MPa, H 900)
- benchmark: ultimate_tensile_strength
value: 1000
unit: MPa
scope: material
conditions:
condition: H1150
basis: typical, room temperature
form: sheet, strip, plate and long products
method: Mechanical properties table, Ultimate Tensile Strength in MPa row
status: ground
source: jacquet-174
where: Mechanical properties table (Ultimate Tensile Strength, MPa, H 1150)
- benchmark: elongation
value: 8
unit: '%'
scope: material
conditions:
condition: Condition A
basis: typical, elongation in 2 in
form: sheet, strip, plate and long products
method: Mechanical properties table, Elongation row, percentage in 2 in
status: ground
source: jacquet-174
where: Mechanical properties table (Elongation row, Condition A)
- benchmark: elongation
value: 10
unit: '%'
scope: material
conditions:
condition: H900
basis: typical, elongation in 2 in
form: sheet, strip, plate and long products
method: Mechanical properties table, Elongation row, percentage in 2 in
status: ground
source: jacquet-174
where: Mechanical properties table (Elongation row, H 900)
- benchmark: elongation
value: 10
unit: '%'
scope: material
conditions:
condition: H1150
basis: typical, elongation in 2 in
form: sheet, strip, plate and long products
method: Mechanical properties table, Elongation row, percentage in 2 in
status: ground
source: jacquet-174
where: Mechanical properties table (Elongation row, H 1150)
- benchmark: yield_strength
value: 1170
unit: MPa
scope: material
conditions:
condition: H900
basis: minimum, ASTM A564 bar table
heat_treatment: 480 C, 1 h, air cool
form: bar and shapes
method: Minimum properties table, 0.2 percent proof stress MPa (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H900 row, proof stress MPa min)
- benchmark: yield_strength
value: 1000
unit: MPa
scope: material
conditions:
condition: H1025
basis: minimum, ASTM A564 bar table
heat_treatment: 550 C, 4 h, air cool
form: bar and shapes
method: Minimum properties table, 0.2 percent proof stress MPa (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H1025 row, proof stress MPa min)
- benchmark: yield_strength
value: 725
unit: MPa
scope: material
conditions:
condition: H1150
basis: minimum, ASTM A564 bar table
heat_treatment: 620 C, 4 h, air cool
form: bar and shapes
method: Minimum properties table, 0.2 percent proof stress MPa (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H1150 row, proof stress MPa min)
- benchmark: ultimate_tensile_strength
value: 1310
unit: MPa
scope: material
conditions:
condition: H900
basis: minimum, ASTM A564 bar table
heat_treatment: 480 C, 1 h, air cool
form: bar and shapes
method: Minimum properties table, tensile strength MPa (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H900 row, tensile MPa min)
- benchmark: ultimate_tensile_strength
value: 1070
unit: MPa
scope: material
conditions:
condition: H1025
basis: minimum, ASTM A564 bar table
heat_treatment: 550 C, 4 h, air cool
form: bar and shapes
method: Minimum properties table, tensile strength MPa (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H1025 row, tensile MPa min)
- benchmark: ultimate_tensile_strength
value: 930
unit: MPa
scope: material
conditions:
condition: H1150
basis: minimum, ASTM A564 bar table
heat_treatment: 620 C, 4 h, air cool
form: bar and shapes
method: Minimum properties table, tensile strength MPa (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H1150 row, tensile MPa min)
- benchmark: elongation
value: 10
unit: '%'
scope: material
conditions:
condition: H900
basis: minimum, ASTM A564 bar table
form: bar and shapes
method: Minimum properties table, elongation percent (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H900 row, elongation min)
- benchmark: elongation
value: 12
unit: '%'
scope: material
conditions:
condition: H1025
basis: minimum, ASTM A564 bar table
form: bar and shapes
method: Minimum properties table, elongation percent (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H1025 row, elongation min)
- benchmark: elongation
value: 16
unit: '%'
scope: material
conditions:
condition: H1150
basis: minimum, ASTM A564 bar table
form: bar and shapes
method: Minimum properties table, elongation percent (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H1150 row, elongation min)
- benchmark: hardness_rockwell_c
value: 40
unit: HRC
scope: material
conditions:
condition: H900
basis: minimum, ASTM A564 bar table
form: bar and shapes
method: Minimum properties table, Hardness Rockwell C (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H900 row, Rockwell C min)
- benchmark: hardness_rockwell_c
value: 35
unit: HRC
scope: material
conditions:
condition: H1025
basis: minimum, ASTM A564 bar table
form: bar and shapes
method: Minimum properties table, Hardness Rockwell C (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H1025 row, Rockwell C min)
- benchmark: hardness_rockwell_c
value: 28
unit: HRC
scope: material
conditions:
condition: H1150
basis: minimum, ASTM A564 bar table
form: bar and shapes
method: Minimum properties table, Hardness Rockwell C (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H1150 row, Rockwell C min)
- benchmark: charpy_impact_energy
value: 20
unit: J
scope: material
conditions:
condition: H1025
basis: minimum, ASTM A564 bar table, Charpy V-notch
form: bar and shapes
method: Minimum properties table, Impact Charpy VJ (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H1025 row, Charpy VJ min)
- benchmark: charpy_impact_energy
value: 41
unit: J
scope: material
conditions:
condition: H1150
basis: minimum, ASTM A564 bar table, Charpy V-notch
form: bar and shapes
method: Minimum properties table, Impact Charpy VJ (min) column
status: ground
source: austral-174
where: Temper table, ASTM A564 Bar and Shapes (H1150 row, Charpy VJ min)
- benchmark: elongation
value: 5
unit: '%'
scope: material
conditions:
condition: H900
basis: minimum, wire datasheet
form: wire
method: Heat treat capabilities (aged) table, elongation min
status: ground
source: ulbrich-wire
where: Heat Treat Capabilities (Aged), H900 elongation min
- benchmark: elongation
value: 5
unit: '%'
scope: material
conditions:
condition: H1025
basis: minimum, wire datasheet
form: wire
method: Heat treat capabilities (aged) table, elongation min
status: ground
source: ulbrich-wire
where: Heat Treat Capabilities (Aged), H1025 elongation min
- benchmark: elongation
value: 8
unit: '%'
scope: material
conditions:
condition: H1150
basis: minimum, wire datasheet
form: wire
method: Heat treat capabilities (aged) table, elongation min
status: ground
source: ulbrich-wire
where: Heat Treat Capabilities (Aged), H1150 elongation min
corrosion:
- environment: Sea water
headline: Carpenter rates sea water as Restricted on its four-level comparative scale.
effect: On Carpenter's comparative scale (Excellent, Good, Moderate, Restricted) sea water is Restricted for 17-4 SELECT, which carries the same UNS S17400 type. The scale is for comparison only and says corrosion testing is recommended. The site rating is mapped as Restricted to severe.
rating: severe
conditions:
medium: sea water
scale: Carpenter comparative rating
source: carp-select
where: Corrosion resistance, comparative rating table (Sea Water row)
- environment: Salt spray (NaCl)
headline: Carpenter rates salt spray as Good.
effect: On Carpenter's comparative scale the salt spray entry for 17-4 SELECT is Good, mapped here to low.
rating: low
conditions:
medium: salt spray (NaCl)
scale: Carpenter comparative rating
source: carp-select
where: Corrosion resistance, comparative rating table (Salt Spray row)
- environment: Humidity
headline: Carpenter rates humidity as Excellent.
effect: On Carpenter's comparative scale the humidity entry for 17-4 SELECT is Excellent, mapped here to low.
rating: low
conditions:
medium: humid air
scale: Carpenter comparative rating
source: carp-select
where: Corrosion resistance, comparative rating table (Humidity row)
- environment: Nitric acid
headline: Carpenter rates nitric acid as Good.
effect: Carpenter's comparative table gives 17-4 SELECT a Good rating in nitric acid, mapped here to low. The table says factors such as temperature, concentration and pH change the result.
rating: low
conditions:
medium: nitric acid
scale: Carpenter comparative rating
source: carp-select
where: Corrosion resistance, comparative rating table (Nitric Acid row)
- environment: Sulfuric acid
headline: Carpenter rates sulfuric acid as Restricted.
effect: Carpenter's comparative table gives 17-4 SELECT a Restricted rating in sulfuric acid, mapped here to severe.
rating: severe
conditions:
medium: sulfuric acid
scale: Carpenter comparative rating
source: carp-select
where: Corrosion resistance, comparative rating table (Sulfuric Acid row)
- environment: Sour oil and gas
headline: Carpenter rates sour oil and gas as Restricted.
effect: Carpenter's comparative table rates sour oil and gas as Restricted for 17-4 SELECT, mapped here to severe. Use the NACE-listed aged conditions for sour service (see the mitigations).
rating: severe
conditions:
medium: sour oil and gas
scale: Carpenter comparative rating
source: carp-select
where: Corrosion resistance, comparative rating table (Sour Oil/Gas row)
- environment: Sea coast atmosphere and salt water service
headline: Sea coast air causes slow light rusting and pitting; salt water use relies on cathodic protection.
effect: Austral Wright says 17-4PH develops overall light rusting and pitting slowly in sea coast atmospheres, and that it is used successfully in salt water as boat shafting with cathodic protection.
rating: unknown
conditions:
medium: sea coast atmosphere; salt water with cathodic protection
source: austral-174
where: Corrosion resistance text (sea coast atmospheres; boat shafting)
- environment: Crevice corrosion in stagnant salt water
headline: Crevice corrosion can occur in stagnant salt water.
effect: Wikipedia says 17-4 is susceptible to crevice corrosion in stagnant salt water, and that its corrosion resistance and machinability are comparable to 304.
rating: unknown
conditions:
medium: stagnant salt water in crevices
source: wiki-174
where: Introduction (corrosion resistance and crevice corrosion statement)
- environment: General corrosion in most media
headline: Corrosion resistance is comparable to Type 304 in most media and superior to the 400 series.
effect: Jacquet states that corrosion resistance is comparable to Type 304 stainless steel in most media and superior to the hardenable 400 series stainless steels. Carpenter's card describes the corrosion resistance as moderate.
rating: low
conditions:
medium: most media
source: jacquet-174
where: Corrosion resistance section
- environment: Peak-aged material in chloride service
headline: Peak-aged material is more susceptible to stress corrosion cracking.
effect: Jacquet says 17-4 is more susceptible to stress corrosion cracking at peak strength. Where chloride stress corrosion cracking is possible, the alloy should be precipitation hardened to the lowest hardness compatible with the use, by heat treating at the highest temperature that still gives the minimum properties.
rating: unknown
conditions:
condition: H900 and other peak-aged conditions
medium: chloride
source: jacquet-174
where: Corrosion resistance section (stress corrosion cracking at peak strength)
- environment: Hardening temperature and stress corrosion cracking
headline: Good stress corrosion resistance comes from hardening at 1025 F (552 C) or higher.
effect: Carpenter says good resistance to stress corrosion cracking is gained by hardening at 1025 F (552 C) and higher, and that 17-4 SELECT withstood corrosive attack better than the 400 series hardenable stainless steels.
rating: unknown
conditions:
temperature: 1025 F (552 C) and higher for aging
source: carp-select
where: Corrosion resistance text (stress corrosion cracking paragraph)
- environment: Overaged condition and stress corrosion cracking
headline: Overaging improves resistance to stress corrosion cracking.
effect: Wikipedia says overaging, meaning aging beyond the peak strength condition, improves resistance to stress corrosion cracking.
rating: unknown
conditions:
condition: overaged (beyond peak strength)
source: wiki-174
where: Introduction (overaging statement)
- environment: Annealed (untempered martensite) material
headline: Annealed material is more sensitive to hydrogen embrittlement and chloride cracking than aged material.
effect: Jacquet says annealed 17-4 has untempered martensite, which may fail by unpredictable brittle fracture and is more sensitive to hydrogen embrittlement and chloride stress corrosion cracking than aged material.
rating: unknown
conditions:
condition: Condition A (annealed)
source: jacquet-174
where: Corrosion resistance section (untempered martensite)
- environment: Sour (NACE) service
headline: H1150M and DH1150 are stocked for NACE service.
effect: voestalpine says it stocks several conditions of 17-4, including H1150M and DH1150, for NACE service. The page gives no crack threshold data.
rating: unknown
conditions:
condition: H1150M and DH1150 (double-aged)
source: voest-174
where: Product page (Stocking the following conditions; NACE service)
risks:
hazards:
- text: 'PubChem aggregated GHS for elemental nickel (Danger): H317 May cause an allergic skin reaction; H351 Suspected of causing cancer; H372 Causes damage to organs through prolonged or repeated exposure; H412 Harmful to aquatic life with long lasting effects. The record covers the element, not the 17-4 PH alloy.'
ghs:
- H317
- H351
- H372
- H412
source: pubchem-nickel
where: Safety and Hazards, GHS Classification (aggregated statements)
- text: 'PubChem GHS for elemental chromium (Danger): H317 May cause an allergic skin reaction; H319 Causes serious eye irritation; H334 May cause allergy or asthma symptoms or breathing difficulties if inhaled. PubChem reports that it does not meet GHS criteria in 50 percent of 2,404 reports.'
ghs:
- H317
- H319
- H334
source: pubchem-chromium
where: Safety and Hazards, GHS Classification (aggregated statements)
- text: 'PubChem GHS for elemental copper (Warning): H400 Very toxic to aquatic life; H410 Very toxic to aquatic life with long lasting effects. PubChem reports that it does not meet GHS criteria in 52.5 percent of 3,463 reports.'
ghs:
- H400
- H410
source: pubchem-copper
where: Safety and Hazards, GHS Classification (aggregated statements)
- text: No safety data sheet for the 17-4 PH alloy was read in this run. The three PubChem records above cover the elements, not the finished alloy.
ghs: []
source: pubchem-nickel
where: Not applicable (gap note)
failure_risks:
- mode: Stress corrosion cracking at peak strength
trigger: Chloride or other corrosive exposure with H900 or other peak-aged material under tensile stress
consequence: Brittle cracking in service; Jacquet says to age to the lowest hardness compatible with the use
severity: high
source: jacquet-174
where: Corrosion resistance section
- mode: Brittle fracture of material left in the annealed condition
trigger: Service or fabrication in Condition A (annealed) without an aging treatment
consequence: Untempered martensite may fail unpredictably and is more sensitive to hydrogen embrittlement and chloride cracking
severity: high
source: jacquet-174
where: Corrosion resistance section; Heat treatment section
- mode: Crevice and pitting corrosion in salt water
trigger: Stagnant salt water, crevices, or sea coast atmosphere
consequence: Crevice corrosion in stagnant salt water; slow light rusting and pitting in sea coast air
severity: moderate
source: wiki-174
where: Introduction (crevice corrosion statement)
- mode: Cracking during plasma torch cutting
trigger: Plasma torch cutting of material in the as-annealed condition, especially plate thicker than about 1 inch (25.4 mm)
consequence: Cracks that may propagate far into the base metal
severity: moderate
source: jacquet-174
where: Cutting section
- mode: Loss of strength from overaging
trigger: Aging above the specified temperature or for too long
consequence: The precipitation reaction passes peak strength, so strength and hardness fall
severity: moderate
source: jacquet-174
where: Heat treatment section (precipitation hardening past peak strength)
side_effects: []
handling:
- text: Do not put annealed (Condition A) material into service; age it to a specified H condition first.
source: jacquet-174
where: Corrosion resistance section; Heat treatment section
- text: Choose the aging temperature for stress corrosion as well as strength. Hardening at 1025 F (552 C) or higher gives good stress corrosion resistance.
source: carp-select
where: Corrosion resistance section
- text: Severe cold working should be done in the H1150 condition, and the part should be re-aged after cold forming.
source: austral-174
where: Fabrication section
- text: Multipass welds must be solution annealed before aging; single-pass welds are precipitation hardened after welding.
source: austral-174
where: Weldability text
- text: Oxyacetylene welding is not recommended because carbon pick-up can occur in the weld; use a 17-4PH type filler.
source: steelforge-174
where: Weldability section
- text: Before plasma torch cutting, age the material at 1150 F (621 C) or higher to lower the cracking risk, then re-solution anneal and re-age after machining.
source: jacquet-174
where: Cutting section
- text: Avoid protective atmospheres containing carbon or nitrogen during heat treatment; they can soften the surface.
source: austral-174
where: Heat treatment text
mitigations:
- text: For NACE sour service, use the H1150M or double-aged DH1150 conditions, which voestalpine stocks for that service.
source: voest-174
where: Product page (NACE service conditions)
- text: Clean and passivate after fabrication, and remove scale, lubricants and drawing coatings, which Carpenter says matter for corrosion resistance.
source: carp-select
where: Corrosion resistance section
- text: Overaging, meaning aging beyond the peak strength condition, improves resistance to stress corrosion cracking.
source: wiki-174
where: Introduction (overaging statement)
uses:
- application: structures
device: Aircraft and missile fittings
example: Carpenter lists aircraft and missile fittings among the applications for 17-4 SELECT, a controlled-residual-stress variant of the UNS S17400 type.
source: carp-select
where: Applications list
- application: mechanisms
device: Bolts and fasteners
example: Austral Wright lists high-strength bolting and fasteners in aerospace and chemical plant applications, and boat propeller shafts. Jacquet lists AMS 7474 bolts.
source: austral-174
where: Typical Applications text
- application: propulsion-and-tanks
device: Jet engine stator vanes
example: Ulbrich lists jet engine stator vanes among the applications for its 17-4 PH wire, and Steelforge lists jet engine parts.
source: ulbrich-wire
where: Applications list
- application: mechanisms
device: Pump shafts, valve parts and rotors
example: voestalpine lists valves, pump shafts and rotors as applications. Steelforge lists oil field valve parts, pump shafts and gears.
source: voest-174
where: Applications list
supply:
- subject: Nickel production by country (world mine, 2025 estimate)
abundance: World mine production 3,900,000 t in 2025 (estimated); world reserves more than 140,000,000 t, of which Indonesia 62,000,000 t (USGS 2026).
producers:
- country: Indonesia
share_percent: 66.7
year: 2025
basis: 2,600,000 t of 3,900,000 t mine production, computed from printed tonnage
- country: Philippines
share_percent: 6.9
year: 2025
basis: 270,000 t of 3,900,000 t, computed
- country: Russia
share_percent: 5.1
year: 2025
basis: 200,000 t of 3,900,000 t, computed
- country: New Caledonia
share_percent: 3.6
year: 2025
basis: 140,000 t of 3,900,000 t, computed
- country: Canada
share_percent: 3.6
year: 2025
basis: 140,000 t of 3,900,000 t, computed
- country: China
share_percent: 3.1
year: 2025
basis: 120,000 t of 3,900,000 t, computed
critical_lists: []
recycling: Nickel recovered from scrap accounted for about 60% of US apparent consumption in 2025; most secondary nickel is stainless-steel scrap.
substitutes:
- Low-nickel, duplex or ultrahigh-chromium stainless steels replace austenitic grades in construction
- Titanium alloys can substitute for nickel or nickel-base alloys in corrosive environments
source: usgs-nickel-2026
where: Salient Statistics; World Mine Production and Reserves; Recycling; Substitutes
- subject: Nickel use in the United States
abundance: Stainless and alloy steel and nickel-containing alloys typically account for more than 85% of domestic consumption. US net import reliance 41% of apparent consumption in 2025 (estimated).
producers: []
critical_lists: []
recycling: Recycled nickel 60% of US apparent consumption in 2025.
substitutes: []
source: usgs-nickel-2026
where: Domestic Production and Use; Salient Statistics (net import reliance)
- subject: Chromium production by country (world mine, 2025 estimate)
abundance: World mine production 51,000 thousand t gross weight in 2025 (estimated); world resources greater than 12 billion t of shipping-grade chromite, with 95% of chromium resources in Kazakhstan and southern Africa.
producers:
- country: South Africa
share_percent: 45.1
year: 2025
basis: 23,000 of 51,000 thousand t gross weight, computed
- country: Turkey
share_percent: 17.6
year: 2025
basis: 9,000 of 51,000 thousand t, computed
- country: Kazakhstan
share_percent: 13.7
year: 2025
basis: 7,000 of 51,000 thousand t, computed
- country: India
share_percent: 5.9
year: 2025
basis: 3,000 of 51,000 thousand t, computed
- country: Brazil
share_percent: 3.9
year: 2025
basis: 2,000 of 51,000 thousand t, computed
- country: Zimbabwe
share_percent: 3.9
year: 2025
basis: 2,000 of 51,000 thousand t, computed
critical_lists: []
recycling: Recycled chromium in stainless-steel scrap receipts was 21% of US apparent consumption in 2025.
substitutes:
- Chromium has no substitute in stainless steel, the leading end use
source: usgs-chromium-2026
where: World Mine Production and Reserves; World Resources; Substitutes; Recycling
- subject: Chromium import reliance
abundance: US net import reliance 79% of apparent consumption in 2025 (estimated).
producers: []
critical_lists: []
recycling: ''
substitutes: []
source: usgs-chromium-2026
where: Salient Statistics (net import reliance)
- subject: Copper production by country (world mine, 2025 estimate)
abundance: World mine production 23,000 thousand t in 2025 (estimated); world reserves 980,000 thousand t (USGS 2026).
producers:
- country: Chile
share_percent: 23
year: 2025
basis: 5,300 of 23,000 thousand t, computed
- country: Congo (Kinshasa)
share_percent: 13.9
year: 2025
basis: 3,200 of 23,000 thousand t, computed
- country: Peru
share_percent: 11.7
year: 2025
basis: 2,700 of 23,000 thousand t, computed
- country: China
share_percent: 7.8
year: 2025
basis: 1,800 of 23,000 thousand t, computed
- country: Russia
share_percent: 5.7
year: 2025
basis: 1,300 of 23,000 thousand t, computed
critical_lists:
- list: U.S. Final 2025 List of Critical Minerals (Federal Register, 7 November 2025)
listed: true
recycling: Old scrap converted to refined metal provided about 160,000 t of copper in 2025, and copper from scrap contributed about 30% of US supply.
substitutes:
- Aluminum substitutes for copper in electrical equipment and power cable; titanium and steel are used in heat exchangers
source: usgs-copper-2026
where: World Mine and Refinery Production; Recycling; Critical minerals text; Substitutes
- subject: Copper use and import reliance in the United States
abundance: US net import reliance 57% of apparent consumption in 2025 (estimated). Building construction takes 42% of copper and copper alloy products, electrical and electronic products 23%.
producers: []
critical_lists: []
recycling: ''
substitutes: []
source: usgs-copper-2026
where: Domestic Production and Use; Salient Statistics (net import reliance)
media: []
documents:
- title: 'Jacquet Metal Service: Technical Sheet 17-4 PH (630), AMS 5604, AMS 5643, ASTM A564'
type: datasheet
url: https://usa.myjacquet.com/wp-content/uploads/sites/55/2025/08/Technical_Sheet_17-4_PH.pdf
year: 2025
- title: 'Carpenter Technology: 17-4 SELECT data sheet, UNS S17400 type'
type: datasheet
url: https://www.carpentertechnology.com/hubfs/Data%20Sheets/17-4%20Select.pdf
- title: 'Carpenter Technology: Custom 630 (17-4) alloy card'
type: datasheet
url: https://www.carpentertechnology.com/hubfs/Alloy%20Cards/Custom_630_(17-4)_snapshot.pdf
year: 2024
- title: 'Austral Wright Metals: Product Data Sheet, Stainless Steel Alloy 17-4PH (UNS S17400)'
type: datasheet
url: https://www.australwright.com.au/technical-data/alloys/stainless-steel/stainless-steel-alloy-17-4ph/
- title: 'United Performance Metals: Datasheet for 17-4 PH stainless steel (AMS 5604, 5643)'
type: datasheet
url: https://www.upmet.com/sites/default/files/datasheets/17-4-ph.pdf
year: 2026
- title: 'Ulbrich Stainless Steels: 17-4 PH UNS S17400 wire datasheet'
type: datasheet
url: https://ulbrich.com/uploads/data-sheets/Stainless-Steel-17-4PH-Wire-UNS-S17400-Wire.pdf
- title: 'AircraftMaterials.com: Stainless Steel 17-4PH (AMS 5643) technical data sheet'
type: datasheet
url: https://aircraftmaterials.com/data/alstst/alstst/ams5643.html
- title: 'voestalpine Specialty Metals UK: 17-4PH (UNS S17400) product page'
type: datasheet
url: https://www.voestalpine.com/specialtymetals/uk/en/17-4ph-uns-s17400/
- title: 'USGS Mineral Commodity Summaries 2026: Nickel'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
year: 2026
- title: 'USGS Mineral Commodity Summaries 2026: Chromium'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
year: 2026
- title: 'USGS Mineral Commodity Summaries 2026: Copper'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-copper.pdf
year: 2026
- title: 'PubChem: Nickel (CID 935), Safety and Hazards, GHS Classification'
type: database
url: https://pubchem.ncbi.nlm.nih.gov/compound/935
year: 2026
- title: 'PubChem: Chromium (CID 23976), Safety and Hazards, GHS Classification'
type: database
url: https://pubchem.ncbi.nlm.nih.gov/compound/23976
year: 2026
- title: 'PubChem: Copper (CID 23978), Safety and Hazards, GHS Classification'
type: database
url: https://pubchem.ncbi.nlm.nih.gov/compound/23978
year: 2026
gaps:
- No fracture toughness (K_IC) value and no Charpy value for H900 or H1150 in the wrought datasheets were read in this run. Charpy values are kept only for H1025 and H1150 (ASTM A564 bar minimums).
- No fatigue strength, creep or elevated-temperature strength value was read.
- The NACE MR0175 and ISO 15156 hardness limit for 17-4 PH (34 to 35 HRC) and the 2020 AMPP sour-gas cracking threshold (45 to 60 percent of SMYS) were seen only in search snippets. Neither page could be read, so neither value is in the file.
- No NASA or ESA report on 17-4 PH was found in this run, so the uses come from supplier and Carpenter sources, not from a space qualification record.
- The Carpenter Custom 630 full datasheet (ASM Alloy Digest SS-258) needs a login and was not read.
- Atlas Steels, the AMPP store page, the DTIC AD0854108 report and the OSTI MR0175 page could not be fetched or were blocked, so they are not used. The Fagersta sheet was read but has no numeric values for this grade.
- The hazard records are for the elements nickel, chromium and copper. No safety data sheet for the 17-4 PH alloy was read.
- Nickel and chromium are not shown on a critical minerals list in the USGS text read. Copper is on the US 2025 list. The EU critical raw materials list was not read.
- USGS shares are mine production only and are computed from printed tonnage. Refinery and smelting shares were not read.
- 'Sources differ and each value keeps its own source: specific heat 419 J/kg.K (Carpenter) and 460 J/kg.K (Upmet); annealed CTE 11.3 (Jacquet) and 11.2 (Upmet); annealed hardness 36 HRC (Carpenter) and 33 HRC (Jacquet, not used).'
- hardness_rockwell_c and charpy_impact_energy are not names in property-canon, so they are kept as snake_case names.
- 'Elongation depends on product form: wire minimums are 5 to 8 percent and bar minimums are 10 to 16 percent. Each row names its form.'
- Austral Wright electrical resistivity values have unclear units, so only the Jacquet values are used.
- No fetched source gives a space environment for this alloy, so the environment tags are empty.
- No DIN designation is printed on the stockist and manufacturer pages read in this run, so none is listed under identity.designations.
- Left out of designations because they name other products, not this grade. These are AMS 5825 and AMS 5827 (welding filler metal), AWS E630 and ER630 (filler metal), CB-7Cu-1 (ASTM A747, which Austral Wright calls the cast equivalent, not the same grade), and Custom 630 (17-4) Project 70+ and 15Cr-5Ni (similar alloys in the Carpenter card).
sources:
jacquet-174:
title: 'Jacquet Metal Service: Technical Sheet 17-4 PH (630)'
id: Technical_Sheet_17-4_PH
url: https://usa.myjacquet.com/wp-content/uploads/sites/55/2025/08/Technical_Sheet_17-4_PH.pdf
kind: datasheet
year: 2025
license: cited, not reproduced
carp-select:
title: 'Carpenter Technology: 17-4 SELECT data sheet'
id: 17-4 SELECT
url: https://www.carpentertechnology.com/hubfs/Data%20Sheets/17-4%20Select.pdf
kind: datasheet
license: cited, not reproduced
carp-card:
title: 'Carpenter Technology: Custom 630 (17-4) alloy card'
id: Custom_630_(17-4)_snapshot
url: https://www.carpentertechnology.com/hubfs/Alloy%20Cards/Custom_630_(17-4)_snapshot.pdf
kind: datasheet
year: 2024
license: cited, not reproduced
austral-174:
title: 'Austral Wright Metals: Product Data Sheet, Stainless Steel Alloy 17-4PH'
id: stainless-steel-alloy-17-4ph
url: https://www.australwright.com.au/technical-data/alloys/stainless-steel/stainless-steel-alloy-17-4ph/
kind: datasheet
license: cited, not reproduced
upmet-174:
title: 'United Performance Metals: Datasheet for 17-4 PH stainless steel'
id: 17-4-ph.pdf
url: https://www.upmet.com/sites/default/files/datasheets/17-4-ph.pdf
kind: datasheet
year: 2026
license: cited, not reproduced
ulbrich-wire:
title: 'Ulbrich Stainless Steels: 17-4 PH UNS S17400 wire datasheet'
id: Stainless-Steel-17-4PH-Wire-UNS-S17400-Wire
url: https://ulbrich.com/uploads/data-sheets/Stainless-Steel-17-4PH-Wire-UNS-S17400-Wire.pdf
kind: datasheet
license: cited, not reproduced
ams5643-page:
title: 'AircraftMaterials.com: Stainless Steel 17-4PH (AMS 5643) technical data sheet'
id: ams5643
url: https://aircraftmaterials.com/data/alstst/alstst/ams5643.html
kind: datasheet
license: cited, not reproduced
voest-174:
title: 'voestalpine Specialty Metals UK: 17-4PH (UNS S17400)'
id: 17-4ph-uns-s17400
url: https://www.voestalpine.com/specialtymetals/uk/en/17-4ph-uns-s17400/
kind: datasheet
license: cited, not reproduced
steelforge-174:
title: 'All Metals and Forge Group: Stainless Steel 17-4 PH report'
id: stainless-steel-17-4-ph
url: https://steelforge.com/stainless-steel-17-4-ph/
kind: web
license: cited, not reproduced
wiki-174:
title: 'Wikipedia: 17-4 stainless steel'
id: 17-4 stainless steel
url: https://en.wikipedia.org/wiki/17-4_stainless_steel
kind: web
license: CC BY-SA 4.0 (cited, not reproduced)
usgs-nickel-2026:
title: 'USGS Mineral Commodity Summaries 2026: Nickel'
id: mcs2026-nickel
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
kind: report
year: 2026
license: public domain
usgs-chromium-2026:
title: 'USGS Mineral Commodity Summaries 2026: Chromium'
id: mcs2026-chromium
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
kind: report
year: 2026
license: public domain
usgs-copper-2026:
title: 'USGS Mineral Commodity Summaries 2026: Copper'
id: mcs2026-copper
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-copper.pdf
kind: report
year: 2026
license: public domain
pubchem-nickel:
title: 'PubChem: Nickel (CID 935), Safety and Hazards, GHS Classification'
id: CID 935
url: https://pubchem.ncbi.nlm.nih.gov/compound/935
kind: database
license: PubChem terms (public)
pubchem-chromium:
title: 'PubChem: Chromium (CID 23976), Safety and Hazards, GHS Classification'
id: CID 23976
url: https://pubchem.ncbi.nlm.nih.gov/compound/23976
kind: database
license: PubChem terms (public)
pubchem-copper:
title: 'PubChem: Copper (CID 23978), Safety and Hazards, GHS Classification'
id: CID 23978
url: https://pubchem.ncbi.nlm.nih.gov/compound/23978
kind: database
license: PubChem terms (public)
license: CC-BY-4.0
updated: '2026-10-24'
review:
status: draft
method: assistant
checked_values: 58
unreachable: 5
caveats: 3
note: 'Written by an AI assistant on 2026-10-24 from pages fetched in this run only. Strength values are kept with their own condition (H900, H1025, H1150, Condition A), form and basis (typical or minimum). Carpenter''s four-level corrosion scale is mapped as Excellent and Good to low, Moderate to moderate, Restricted to severe. Unreachable: Atlas Steels, AMPP store, DTIC, OSTI and the Boeing H900 page.'
story:
recipe:
line: 17-4 PH is an iron-based martensitic precipitation-hardening stainless steel, UNS S17400 (AISI 630), made to the composition limits in the identity record with iron as the balance. It is supplied in the annealed condition, after a high-temperature solution treatment. One aging step at 480 to 620 C (900 to 1150 F) precipitates a copper-based phase that gives the strength (Austral Wright; Jacquet). Product forms are bar, sheet, plate, wire and forgings.
parts:
- name: Iron
symbol: Fe
share_note: balance (the rest)
role: Matrix of the alloy, martensitic when annealed.
- name: Chromium
symbol: Cr
share_percent: 15
share_high: 17.5
role: Gives the passive film that resists rust; corrosion close to Type 304 in most media (Jacquet).
- name: Nickel
symbol: Ni
share_percent: 3
share_high: 5
role: 'Part of the chromium-nickel-copper martensitic alloy (Carpenter: about 17 percent Cr and 4 percent Ni).'
- name: Copper
symbol: Cu
share_percent: 3
share_high: 5
role: Forms a copper-based phase on aging, which gives the high strength (Austral Wright).
- name: Niobium plus tantalum
symbol: Nb+Ta
share_percent: 0.15
share_high: 0.45
role: Columbium plus tantalum, a listed alloying addition (Jacquet; Carpenter).
- name: Carbon
symbol: C
share_percent: 0
share_high: 0.07
limit: maximum
role: Kept low; Carpenter gives a maximum of 0.070 percent.
- name: Manganese
symbol: Mn
share_percent: 0
share_high: 1
limit: maximum
role: Residual element, maximum 1.00 percent.
- name: Silicon
symbol: Si
share_percent: 0
share_high: 1
limit: maximum
role: Residual element, maximum 1.00 percent.
- name: Phosphorus
symbol: P
share_percent: 0
share_high: 0.04
limit: maximum
role: Impurity held low, maximum 0.040 percent.
- name: Sulfur
symbol: S
share_percent: 0
share_high: 0.03
limit: maximum
role: Impurity held low, maximum 0.030 percent.
risk_groups:
- title: For people
level: 0
verdict: No safety data sheet for the alloy was read
lead: The PubChem records below cover elemental nickel, chromium and copper, not the finished 17-4 PH alloy.
points:
- label: Nickel
line: PubChem lists elemental nickel as Danger, with H317 (skin sensitiser), H351 (suspected carcinogen) and H372 (organ damage on repeated exposure).
- label: Chromium
line: PubChem lists elemental chromium as Danger with H317, H319 and H334 in notifications that carry hazard codes.
- label: Copper
line: PubChem lists elemental copper as Warning, with H400 and H410 for aquatic life.
- label: Workshop
line: Check the supplier safety data sheet before cutting, grinding or welding this alloy.
- title: In the environment
level: 1
verdict: Chloride and stagnant water are the watch points
lead: Crevice corrosion and stress corrosion cracking are the main failure routes in service.
points:
- label: Sea water
line: Carpenter rates sea water as Restricted for 17-4 SELECT. Austral Wright uses it in salt water as boat shafting only with cathodic protection.
- label: Crevices
line: Wikipedia says it is susceptible to crevice corrosion in stagnant salt water.
- label: Sour service
line: Carpenter rates sour oil and gas as Restricted. voestalpine stocks H1150M and DH1150 for NACE service.
- title: Heat treatment and fabrication
level: 1
verdict: The aging temperature sets both strength and cracking risk
lead: The highest strength comes from the H900 condition, which is also the most prone to stress corrosion cracking.
points:
- label: Peak aging
line: Jacquet says 17-4 is more susceptible to stress corrosion cracking at peak strength, so the lowest hardness compatible with the use is preferred.
- label: Annealed
line: Untempered martensite in the annealed condition may fail unpredictably and is more sensitive to hydrogen embrittlement (Jacquet).
- label: Torch cutting
line: Plasma torch cutting of annealed plate can crack the metal, especially plate thicker than about 1 inch (Jacquet).
why: 17-4 PH gives high strength from a simple one-step aging treatment, with corrosion resistance close to Type 304 in most media (Jacquet). Its weak point is that the highest strength comes with the greatest risk of stress corrosion cracking, so the aging condition is chosen for the environment as well as the load.
uses:
- where: Aircraft and missile fittings
line: Carpenter lists aircraft and missile fittings for its 17-4 SELECT variant, and Steelforge lists forged aircraft fittings.
- where: Bolts and fasteners
line: Austral Wright lists high-strength bolting and fasteners in aerospace and chemical plant use, and Jacquet lists AMS 7474 bolts.
- where: Jet engine and pump parts
line: Ulbrich lists jet engine stator vanes, voestalpine lists pump shafts and rotors, and Steelforge lists valve parts and pump shafts.
- where: Chemical, food and medical equipment
line: Ulbrich lists chemical, petrochemical and food processing equipment and surgical instruments, and Wikipedia lists medical devices and firearms.
can_do:
- label: Strength
benchmark: yield_strength
line: Minimum yield is 1170 MPa in H900 and 725 MPa in H1150 for ASTM A564 bar (Austral Wright). Typical yield for cold-finished bar is 1262 MPa in H900 (Carpenter).
- label: Stiffness
benchmark: elastic_modulus
line: Elastic modulus is 196 GPa in all conditions (Jacquet), and Austral Wright prints 200 to 201 GPa in tension.
- label: Hardness
benchmark: hardness_rockwell_c
line: Typical hardness is 44 HRC in H900 and 33 HRC in H1150 for cold-finished bar (Carpenter). Minimum hardness is 40 HRC in H900 (Austral Wright).
- label: Heat
benchmark: max_service_temp
line: High strength is kept to about 316 C (600 F) (Jacquet).
compare: Jacquet says the corrosion resistance of 17-4 PH is comparable to Type 304 in most media and superior to the hardenable 400 series. Carpenter says its 17-4 SELECT variant approaches Type 304 in most corrodents and is better than the 400 series, while Carpenter's card calls the corrosion resistance moderate. Jacquet also says H900 gives the highest strength of this family, slightly below other precipitation-hardening grades that need more heat-treatment steps.
compare_rows:
- scope: material
label: Yield strength
benchmark: yield_strength
- scope: material
label: Elastic modulus
benchmark: elastic_modulus
- scope: material
label: Melting range
benchmark: melting_point
handling:
- Do not use annealed (Condition A) material in service. Age it to a specified H condition first (Jacquet).
- Choose the aging temperature for stress corrosion as well as strength. Hardening at 1025 F (552 C) or higher gives good stress corrosion resistance (Carpenter).
- Weld with matching filler and solution anneal multipass welds before aging (Austral Wright). Avoid oxyacetylene welding (Steelforge).
good_for:
- Fittings, fasteners and shafts where strength matters and exposure is mild, such as rural and mild industrial air (Austral Wright).
- Parts that can be aged to H1150 or double-aged for NACE sour service (voestalpine).
watch_out:
- Peak-aged H900 material is most prone to stress corrosion cracking. Age higher when chloride or sour service is possible (Jacquet; Carpenter).
- Crevice corrosion in stagnant salt water, and Restricted for sea water in Carpenter's table (Wikipedia; Carpenter).
- Annealed material is brittle and should not be used. Plasma torch cutting can crack it (Jacquet).
verdict: '17-4 PH is the strong, moderately corrosion-resistant choice when a one-step age can set the strength. The aging condition is the design decision: H900 gives the most strength and the most stress corrosion risk, and H1150 gives more toughness and margin. For sea water or sour service, choose an overaged or NACE-listed condition and check the data for that condition.'
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.