Phynox UNS R30003
Cobalt-base austenitic alloy. Aperam nominal composition (wt %): Co 40, Cr 20, Ni 16, Fe 15, Mo 7
Also known as UNS R30003, EN 2.4711, EN name CoCr20Ni15Mo, ASTM F1058, AMS 5833, AMS 5834 · 4 more
Phynox (UNS R30003, EN 2.4711, also sold as Elgiloy) is a cobalt-base alloy of cobalt, chromium, nickel, molybdenum and iron.
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 in cold rolled strip
2500 MPa
Stiffness in the wire sheet
190 GPa
Operating range
-184 to 454 C
Recipe, share of the weight
- Co 40%Cobalt
- Cr 20%Chromium
- Ni 16%Nickel
- Mo 7%Molybdenum
- Fe 15%Iron
- Mn not statedManganese
- C not statedCarbon
Best for
Thin, high-strength springs and diaphragms that must stay non-magnetic and resist corrosion in seawater and sour wells
Weakest at
Joining after age hardening, and no measured corrosion rates in the sources read
Risk at a glance
- People Low. Unverified for this alloy
- If it fails Moderate. Hardening lost or limited after welding
- Corrosion Low. Virtually immune to crevice, stress corrosion and pitting in seawater, even at the highest strength levels.
Quick facts: UNS R30003
| Property | Value | Basis |
|---|---|---|
| Density | 8.3 g/cm³ | 1 sourced value |
| Yield strength | 1,800 MPa | 1 sourced value |
| Tensile strength | 689 to 2,620 MPa | 8 sourced values across conditions |
| Young's modulus | 186 to 221 GPa | 4 sourced values across conditions |
| Thermal conductivity | 12.5 W/(m·K) | 1 sourced value |
| Thermal expansion (CTE) | 12.5 to 15.2 ppm/K | 2 sourced values across conditions |
| Specific heat | 450 J/(kg·K) | 1 sourced value |
| Electrical resistivity | 9.5e-7 to 0.000001 Ω·m | 2 sourced values across conditions |
| Maximum service temperature | 454 °C | 1 sourced value |
What is the density of Phynox (UNS R30003)?
Phynox (UNS R30003) has a density of 8.3 g/cm³. The source and test conditions are listed in the properties table on this page.
What is the thermal conductivity of Phynox (UNS R30003)?
Phynox (UNS R30003) has a thermal conductivity of 12.5 W/(m·K). The source and test conditions are listed in the properties table on this page.
What is the coefficient of thermal expansion of Phynox (UNS R30003)?
Phynox (UNS R30003) has a coefficient of thermal expansion of 12.5 to 15.2 ppm/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 yield strength of Phynox (UNS R30003)?
Phynox (UNS R30003) has a yield strength of 1,800 MPa. The source and test conditions are listed in the properties table on this page.
What is the tensile strength of Phynox (UNS R30003)?
Phynox (UNS R30003) has a tensile strength of 689 to 2,620 MPa. The range covers 8 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 Phynox (UNS R30003)?
Phynox (UNS R30003) is also written as UNS R30003, EN 2.4711, EN name CoCr20Ni15Mo, ASTM F1058, AMS 5833, AMS 5834. Each code is printed in the source listed beside it in the designations table.
What is Phynox (UNS R30003) used for?
Uses recorded in the sources include Helical and shaped springs; Parts for satellite communications equipment; Watch springs and axles.
Why it exists
Phynox is a non-magnetic cobalt alloy that the manufacturers describe as strong, tough and corrosion resistant. Aperam says cold rolled strip reaches up to 2500 MPa and that cold work alone can give more than 1800 MPa yield strength. The listed uses are springs, diaphragms, electrical apparatus, aerospace equipment, surgical implants and pacemaker electrodes. The sources read here give no spacecraft flight record.
Where it's used
Springs
Aperam lists helical, shaped and printer springs among the applications.
Satellite communications equipment
The Elgiloy strip sheet lists satellite communications equipment among its applications, without naming a mission.
Watch springs and axles
Studer says Phynox is a popular material for springs and axles in the watch industry.
Recipe
Cobalt-base austenitic alloy. Aperam nominal composition (wt %): Co 40, Cr 20, Ni 16, Fe 15, Mo 7
Phynox is a cobalt-base austenitic alloy of cobalt, chromium, nickel, molybdenum and iron, with manganese and a little carbon. Aperam gives the nominal composition as Co 40, Cr 20, Ni 16, Fe 15 and Mo 7 (weight percent). Studer describes the product as annealed at 1050 C and then cold worked and age hardened at 480 to 540 C for 2 to 5 h under vacuum or argon. The sources read here do not describe how the alloy is melted.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Cobalt Co | 40% | Main element. Aperam gives 40 percent as the nominal value, and Studer says the alloy contains 40 percent cobalt. |
| Chromium Cr | 20% | Major element for corrosion resistance. The sources give it no separate role. |
| Nickel Ni | 16% | Austenite former. Studer gives 16 percent; the Elgiloy sheets give a range of 14 to 18 percent. |
| Molybdenum Mo | 7% | Alloying element. Studer gives 7 percent; the Elgiloy sheets give a range of 6 to 8 percent. |
| Iron Fe | 15% | Nominal value from Aperam. Studer and the Elgiloy sheets list iron as the balance. |
| Manganese Mn | not stated | Alloying element. The Elgiloy strip sheet prints a range only, and no nominal value is printed. |
| Carbon C | not stated | Minor element. The Elgiloy sheets print a maximum only. |
Weight shares are as printed in the sources.
What it can do
Strength in cold rolled strip
2500 MPa
measured
Aperam gives up to 2500 MPa for cold rolled strip in the fully hardened condition.
Stiffness in the wire sheet
190 GPa
measured
The Elgiloy wire sheet gives 190 GPa at 20 C. Studer gives 215 GPa for flat wire at the same temperature.
Operating range
-184 to 454 C
measured
Both Elgiloy sheets give a suggested operating range of -300 to 850 F (-184 to 454 C) for all listed tempers.
How it compares
Phynox and Elgiloy are the same alloy under two trade names. In the Elgiloy wire sheet the annealed tensile range is 120 to 150 ksi, and the spring temper and aged range is 260 to 330 ksi. The Elgiloy strip sheet gives up to 380 ksi for spring temper strip that is aged. The sheets come from one manufacturer, and the datasheet values are typical, not minimums, so read them as examples, not a ranking against other alloys.
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 | UNS R30003 | UNS R30605 | UNS R30004 |
|---|---|---|---|
| Thermal behavior and safety | |||
| Thermal conductivity at 20 C | 12.5 W/(m.K)8 | 9.4 W/m·K | 13 W/(m·K) |
| Specific heat capacity at 20 C | 450 J/(kg.K)9 | no data | no data |
| Physical and electrical | |||
| Density | 8.3 g/cm³1 | 9.13 g/cm³ | 0.3 lb/in3 |
| Specific electrical resistance at 20 C, Studer | 95 uOhm.cm10 | 89 µΩ·cm | 92 µΩ·cm |
| Electrical resistivity at 20 C, wire sheet | 99.6 uOhm.cm11 | 89 µΩ·cm | 92 µΩ·cm |
| Other measurements | |||
| Young's modulus at 20 C, flat wire | 215 GPa2 | 225 GPa | 29.5 psi x 10^6 |
| Modulus of elasticity at 20 C, wire | 190 GPa3 | 225 GPa | 29.5 psi x 10^6 |
| Modulus of elasticity, cold reduced stripPrinted as a range in the Elgiloy strip sheet. | 186 GPa4 | 225 GPa | 29.5 psi x 10^6 |
| Modulus of elasticity, cold reduced and aged strip | 206 GPa5 | 225 GPa | 29.5 psi x 10^6 |
| Coefficient of thermal expansion, 20 to 200 C | 12.5 10-6/K6 | 14.4 µm/m·°C | 12.5 µm/m·°C |
| Coefficient of thermal expansion, 20 to 300 C, wire sheet | 15.2 um/m-C7 | 14.4 µm/m·°C | 12.5 µm/m·°C |
| Tensile strength, annealed wire | 120 ksi12 | > 896 MPa | 1.4×10^5 psi |
| Tensile strength, spring temper wire | 220 ksi13 | > 896 MPa | 1.4×10^5 psi |
| Tensile strength, spring temper and aged wire | 260 ksi14 | > 896 MPa | 1.4×10^5 psi |
| Tensile strength, annealed strip | 100 ksi15 | > 896 MPa | 1.4×10^5 psi |
| Tensile strength, spring temper strip, no heat treatment | 310 ksi16 | > 896 MPa | 1.4×10^5 psi |
| Tensile strength, spring temper strip and aged | 380 ksi17 | > 896 MPa | 1.4×10^5 psi |
| Tensile strength, hardened wire, over 2200 | 2200 N/mm218 | > 896 MPa | 1.4×10^5 psi |
| Tensile strength, cold rolled strip, fully hardened | 2500 MPa19 | > 896 MPa | 1.4×10^5 psi |
| Yield strength, cold worked | 1800 MPa20 | > 379 MPa | 70000 psi |
| Suggested maximum operating temperature | 454 °C21 | 1800 °F | no data |
| Suggested minimum operating temperature | -184 °C22 | no data | no data |
Why choose it, and why not
Good for
- Springs and diaphragms: up to 2500 MPa in cold rolled strip, per Aperam.
- Non-magnetic parts: Studer says the alloy can be considered non-magnetic over the whole temperature range.
- Seawater and sour wells: the Elgiloy sheets say it is virtually immune to crevice and pitting attack in seawater and highly resistant to sulfide stress cracking.
Watch out for
- Heat treatment in air: the surface forms a yellow oxide layer.
- No measured corrosion rates: the corrosion ratings rest on qualitative statements.
- Conflicting values: modulus and resistivity differ between the Studer and Elgiloy sheets.
- No Phynox-specific SDS, no flight record and no measured elongation or hardness were found in this run.
Phynox is a strong, non-magnetic cobalt-base spring alloy, and the manufacturers' data support its use in springs, diaphragms and thin strip. The sources read here give qualitative corrosion resistance, no measured corrosion rates and no spacecraft flight record.
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 | R30003 |
| EN | 2.4711 |
| EN name | CoCr20Ni15Mo |
| ASTM | F1058 (surgical implant wire and strip) |
| AMS | 5833, 5834, 5876 |
| ISO | 5832-7 |
| Trade name | Phynox, Elgiloy |
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Density | Printed in the Physical Properties table of the Elgiloy wire sheet. Studer SBA-011 prints the same 8.3 g/cm3 without a temperature. | temperature 20 Cunit in source 8.30 g/cm3 at 20 C (also 0.300 lb/in3) | — |
| 2 | Young's modulus at 20 C, flat wire | Printed in the Physical properties table of the Studer SBA-011 datasheet. The Elgiloy wire sheet prints a lower value for round wire (190 GPa), and both are recorded. | temperature 20 Cform flat wireunit in source 215.00 GPA | — |
| 3 | Modulus of elasticity at 20 C, wire | Printed in the Physical Properties table of the Elgiloy wire sheet. The Studer datasheet prints 215 GPa at 20 C for flat wire, and both are recorded. | temperature 20 Cform wireunit in source 190 GPa at 20 C | — |
| 4 | Modulus of elasticity, cold reduced strip | — | temper cold reducedform stripunit in source 186 to 200 GPa cold reduced | — |
| 5 | Modulus of elasticity, cold reduced and aged strip | Printed as a range in the Elgiloy strip sheet. Aging is the printed heat treatment in that sheet. | temper cold reduced and agedform stripunit in source 206 to 221 GPa cold reduced and aged | — |
| 6 | Coefficient of thermal expansion, 20 to 200 C | Printed in the Physical properties table of the Studer datasheet. | temperature 20 to 200 Cunit in source 12.5 [10-6/K] | — |
| 7 | Coefficient of thermal expansion, 20 to 300 C, wire sheet | Printed in the Physical Properties table of the Elgiloy wire sheet. The same sheet gives 8.4 microinches per inch per F for 70 to 600 F. The two values are recorded separately because the temperature ranges differ. | temperature 20 to 300 Cunit in source 15.2 um/m-oC (20-300 oC) | — |
| 8 | Thermal conductivity at 20 C | Printed in the Physical properties table of the Studer datasheet. The Elgiloy wire sheet prints the same 12.5 W/m-K at 20 C. | temperature 20 Cunit in source 12.5 W/m K | — |
| 9 | Specific heat capacity at 20 C | Printed in the Physical properties table of the Studer datasheet. | temperature 20 Cunit in source 450 J/kgK | — |
| 10 | Specific electrical resistance at 20 C, Studer | Printed in the Physical properties table of the Studer datasheet. The Elgiloy wire sheet prints 99.6 uOhm.cm at 20 C, and both are recorded. | temperature 20 Cunit in source 95 uOhm cm | — |
| 11 | Electrical resistivity at 20 C, wire sheet | Printed in the Physical Properties table of the Elgiloy wire sheet. The Elgiloy strip sheet prints the same 99.6 micro ohm.cm at 20 C. | temperature 20 Cunit in source 99.6 micro ohm.cm | — |
| 12 | Tensile strength, annealed wire | Typical Mechanical Properties table, Spring Applications, Elgiloy wire sheet. The MPa range is printed beside the ksi range. | temper annealedform wireheat treatment 2048 F (1120 C)unit in source 120 to 150 ksi (830 to 1035 MPa) | — |
| 13 | Tensile strength, spring temper wire | Typical Mechanical Properties table, Spring Applications, Elgiloy wire sheet. | temper spring temper, no agingform wireunit in source 220 to 290 ksi (1515 to 2000 MPa) | — |
| 14 | Tensile strength, spring temper and aged wire | Typical Mechanical Properties table, Spring Applications, Elgiloy wire sheet. The aging step is printed in the same row. | temper spring temper and aged, aged at 980 F (527 C) for 5 h after coilingform wireunit in source 260 to 330 ksi (1790 to 2275 MPa) | — |
| 15 | Tensile strength, annealed strip | Typical Mechanical Properties table, Elgiloy strip sheet. The value is printed as a minimum. | temper annealed per AMS 5876form stripunit in source 100 ksi min (690 MPa) | — |
| 16 | Tensile strength, spring temper strip, no heat treatment | Typical Mechanical Properties table, Elgiloy strip sheet. The value is printed as up to. | temper spring temper, no heat treatmentform stripunit in source up to 310 ksi (2100 MPa) | — |
| 17 | Tensile strength, spring temper strip and aged | Typical Mechanical Properties table, Elgiloy strip sheet. The value is printed as up to. | temper spring temper after cold rolling, then aged per AMS 5876form stripunit in source up to 380 ksi (2600 MPa) | — |
| 18 | Tensile strength, hardened wire, over 2200 | Printed in the Technical main features section of the Studer datasheet. The value is printed as over 2200 N/mm2 and depends on diameter, so it is a lower bound. | temper hardened by the heat treatment in the Studer datasheetform flat wireunit in source over 2200 N/mm2, depending on diameter | — |
| 19 | Tensile strength, cold rolled strip, fully hardened | Printed on the Aperam PHYNOX product page, first paragraph. The value is printed as up to. | temper cold rolled strip, fully hardenedform stripunit in source up to 2500 MPa | — |
| 20 | Yield strength, cold worked | Printed on the Aperam PHYNOX product page. The page gives it as higher than 1800 MPa that can be achieved by cold working alone. | temper cold worked, no agingunit in source higher than 1800 MPa | — |
| 21 | Suggested maximum operating temperature | Printed as the suggested operating range in the Typical Mechanical Properties tables of both Elgiloy sheets. | temper all listed tempersunit in source -300 F to 850 F (-184 C to 454 C) | — |
| 22 | Suggested minimum operating temperature | Printed as the suggested operating range in the Typical Mechanical Properties table of the Elgiloy wire sheet. The Elgiloy strip sheet prints the same range. | temper all listed tempersunit in source -300 F to 850 F (-184 C to 454 C) | — |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Seawater, crevice and pitting | low | Virtually immune to crevice, stress corrosion and pitting in seawater, even at the highest strength levels.1 |
| Sour well environments, sulfide stress cracking | low | Highly resistant to sulfide stress corrosion cracking; NACE MR0175 is an applicable specification.2 |
| Mineral and organic acids at room temperature | low | Not, or only very hardly, attacked by mineral and organic acids at room temperature.3 |
| Stress corrosion cracking and hydrogen embrittlement in service | low | Exceptional resistance to corrosion, stress corrosion cracking and hydrogen embrittlement, per the manufacturer.4 |
| Air during heat treatment | low | Discolours in air; a treatment in air leaves a yellow oxide layer with no effect on mechanical properties.5 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Seawater, crevice and pitting | The Elgiloy wire sheet says that in seawater the alloy is virtually immune to crevice and stress corrosion and to pitting, even at the highest strength levels. No seawater test duration or rate is printed. | basis qualitative statement, no rate printedproduct wire and strip, all strength levels |
| 2 | Sour well environments, sulfide stress cracking | The Elgiloy wire sheet says the alloy is highly resistant to sulfide stress corrosion cracking and is the alloy of choice in the most demanding sour well environments. Both Elgiloy sheets list NACE MR0175 in their applicable specifications. No test figure is printed. | basis qualitative statement, no test figure printed |
| 3 | Mineral and organic acids at room temperature | The Studer SBA-011 datasheet says the alloy is not or only very hardly attacked by organic and mineral acids at room temperature, and that it outshines the best stainless steels. No acid concentration or rate is printed. | temperature room temperaturebasis qualitative statement, no rate printed |
| 4 | Stress corrosion cracking and hydrogen embrittlement in service | Aperam lists exceptional resistance to corrosion, stress corrosion cracking and hydrogen embrittlement among the most important properties of the alloy. The page prints no test data. | basis manufacturer statement, no test data printed |
| 5 | Air during heat treatment | Studer says the material discolours in air and that this has no effect on its mechanical properties. Its thermal treatment table says a treatment in air causes a yellow oxide layer, and it recommends vacuum or argon. | temperature 480 to 540 C hardeningbasis qualitative statement |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
No Phynox safety data sheet was found. The hazard data here are PubChem's cobalt summary, so they describe cobalt metal rather than this alloy.
- Sensitisation
- PubChem's aggregated cobalt data lists H317 and H334, which mean an allergic skin reaction and allergy or breathing difficulties if inhaled.
- Carcinogenicity and fertility
- The same summary lists H350 (may cause cancer), H360F (may damage fertility) and H341 (suspected of causing genetic defects).
- Dust and fume
- No Phynox-specific fume statement was in the sources read. Studer says machining is difficult and slow.
If it fails
The failure routes in the sources are about welding after hardening and about reheating. The sources report no service failure in space.
- Welding after hardening
- Only strain hardened material can be hardened, so welded areas should not carry major stress after hardening.
- Corrosion
- The sources give qualitative corrosion resistance only, with no measured rate in seawater, acid or sour service.
Handling and storage
- Heat treatment
- Anneal at 1050 C for 0.5 h, then harden at 480 to 540 C for 2 to 5 h, preferably under vacuum or argon.
- Stress relief
- Stress relieve cold rolled products before machining.
- Machining
- Machining is difficult. Use slow cutting speeds of about 20 to 40 m/min and moderate to strong feeds.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Hardening lost or limited after weldingmoderate severity | Welding an already hardened partStuder says only strain hardened material can be hardened, and welded areas should not carry major mechanical stress once the material is hardened. |
Side effects on surrounding parts
| Affects | Effect |
|---|---|
| Surface finish; the datasheet says this does not change mechanical properties. | Heat treatment in air forms a yellow oxide layer on the surface. |
Handling and storage
- Anneal at 1050 C for 0.5 h and cool rapidly in air, gas or water. Stress relief cold rolled products before machining.
- Harden at 480 to 540 C for 2 to 5 h, preferably under vacuum or in argon. Keep all heat treatments in a hydrogen free atmosphere.
- Machining is difficult. Studer gives a cutting speed of about 20 to 40 m/min, with moderate to strong feed.
- The alloy can be welded and soldered, but only strain hardened material can be hardened.
Mitigations
- Heat treat under vacuum or in argon, so the surface does not form the yellow oxide layer.
Supply and geography
How common the raw materials are and where they come from.
Cobalt (40 percent nominal)
- Top producers (2025)
- Congo (Kinshasa) 73%, Indonesia 14%
- Recycling
- USGS: in 2025, cobalt content of purchased scrap represented 25 percent of estimated cobalt consumption. USGS says 51 percent of cobalt consumed in the United States went into superalloys, mainly for aircraft gas turbine engines.
- Substitutes
- USGS: depending on the application, substitution for cobalt could result in a loss in product performance or increased cost.
Chromium (20 percent nominal)
- Top producers (2025)
- South Africa 45.1%, Turkey 17.6%, Kazakhstan 13.7%, India 5.9%
- Recycling
- USGS: in 2025, recycled chromium in reported stainless steel scrap receipts accounted for 21 percent of apparent consumption.
- Substitutes
- USGS: chromium has no substitute in stainless steel, the leading end use, or in superalloys, the major strategic end use.
Molybdenum (7 percent nominal)
- Top producers (2025)
- China 37.3%, Chile 16.2%, Peru 15%, Mexico 6.5%
- Recycling
- USGS: molybdenum is recycled as a component of catalysts, ferrous scrap and superalloy scrap. The USGS summary gives no recycled share for molybdenum.
- Substitutes
- USGS: there is little substitution for molybdenum in its major application in steels and cast irons. Potential substitutes in alloy steels include boron, chromium, niobium and vanadium.
Nickel (16 percent nominal)
- Top producers (2025)
- Indonesia 66.7%, Philippines 6.9%, Russia 5.1%
- Recycling
- USGS: most secondary nickel was in the form of nickel content of stainless steel scrap, and most recycled nickel was used to make new alloys.
- Substitutes
- USGS: low-nickel, duplex or ultrahigh-chromium stainless steels have been substituted for austenitic grades in some applications. Titanium alloys can substitute for nickel-base alloys in corrosive environments.
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: phynox
spore_version: 0.2
family: cobalt-alloys
name: Phynox
abbreviation: UNS R30003
role: non-magnetic cobalt-base spring alloy, also sold as Elgiloy, for high-strength springs, diaphragms and thin strip
category: metals
type: nickel-superalloys
summary: |
Phynox (UNS R30003, EN 2.4711, also sold as Elgiloy) is a cobalt-base alloy of cobalt, chromium, nickel, molybdenum and iron. Aperam gives its nominal composition as 40 Co, 20 Cr, 16 Ni, 15 Fe and 7 Mo (weight percent). It gets its strength from cold work and can be age hardened at about 500 C. Aperam says cold rolled strip reaches up to 2500 MPa tensile strength. The alloy is non-magnetic. Its listed uses are springs, diaphragms, electrical and electronic apparatus, aerospace equipment, and surgical implants and pacemaker electrodes. Elgiloy strip data are also used for satellite communications equipment, but no spacecraft is named.
best_for: Thin, high-strength springs and diaphragms that must stay non-magnetic and resist corrosion in seawater and sour wells
weakest_at: Joining after age hardening, and no measured corrosion rates in the sources read
identity:
formula: 'Cobalt-base austenitic alloy. Aperam nominal composition (wt %): Co 40, Cr 20, Ni 16, Fe 15, Mo 7'
source: aperam-phynox
where: Chemical Composition table on the PHYNOX product page (Co40 Cr20 Ni16 Fe15 Mo7)
designations:
- system: UNS
code: R30003
source: elgiloy-wire-sheet
where: Title block and Applicable Specifications table (Wire and Bar)
- system: EN
code: '2.4711'
source: studer-phynox-sba011
where: Material number column, title block
- system: EN name
code: CoCr20Ni15Mo
source: studer-phynox-sba011
where: EN/DIN column, title block
- system: ASTM
code: F1058
note: surgical implant wire and strip
source: studer-phynox-sba011
where: ASTM column, title block; also Applicable Specifications in both Elgiloy sheets
- system: AMS
code: '5833'
source: elgiloy-wire-sheet
where: Applicable Specifications, Wire and Bar row
- system: AMS
code: '5834'
source: elgiloy-wire-sheet
where: Applicable Specifications, Wire and Bar row
- system: AMS
code: '5876'
source: elgiloy-strip-sheet
where: Applicable Specifications, Strip and Foil row
- system: ISO
code: 5832-7
source: elgiloy-wire-sheet
where: Applicable Specifications, Wire and Bar row
- system: Trade name
code: Phynox
source: aperam-phynox
where: Product page title and datasheet name
- system: Trade name
code: Elgiloy
source: elgiloy-wire-sheet
where: Title block; registered trademark of Elgiloy Specialty Metals
tags:
environments: []
stresses:
- extreme-cold
- extreme-heat
applications:
- mechanisms
- electronics-and-chips
properties:
- benchmark: density
label: Density
value: 8.3
unit: g/cm3
scope: material
conditions:
temperature: 20 C
unit_in_source: 8.30 g/cm3 at 20 C (also 0.300 lb/in3)
method: Printed in the Physical Properties table of the Elgiloy wire sheet. Studer SBA-011 prints the same 8.3 g/cm3 without a temperature.
status: ground
source: elgiloy-wire-sheet
where: Physical Properties table, row Density, At 20 C column
- benchmark: elastic_modulus
label: Young's modulus at 20 C, flat wire
value: 215
unit: GPa
scope: material
conditions:
temperature: 20 C
form: flat wire
unit_in_source: 215.00 GPA
method: Printed in the Physical properties table of the Studer SBA-011 datasheet. The Elgiloy wire sheet prints a lower value for round wire (190 GPa), and both are recorded.
status: ground
source: studer-phynox-sba011
where: Physical properties table, row Young's modulus E, 20 C
- benchmark: elastic_modulus
label: Modulus of elasticity at 20 C, wire
value: 190
unit: GPa
scope: material
conditions:
temperature: 20 C
form: wire
unit_in_source: 190 GPa at 20 C
method: Printed in the Physical Properties table of the Elgiloy wire sheet. The Studer datasheet prints 215 GPa at 20 C for flat wire, and both are recorded.
status: ground
source: elgiloy-wire-sheet
where: Physical Properties table, row Modulus of Elasticity (E), At 20C column
- benchmark: elastic_modulus
label: Modulus of elasticity, cold reduced strip
value: 186
value_high: 200
unit: GPa
scope: material
conditions:
temper: cold reduced
form: strip
unit_in_source: 186 to 200 GPa cold reduced
method: Printed as a range in the Elgiloy strip sheet.
status: ground
source: elgiloy-strip-sheet
where: Physical Properties table, row Modulus of Elasticity (E), cold reduced line
- benchmark: elastic_modulus
label: Modulus of elasticity, cold reduced and aged strip
value: 206
value_high: 221
unit: GPa
scope: material
conditions:
temper: cold reduced and aged
form: strip
unit_in_source: 206 to 221 GPa cold reduced and aged
method: Printed as a range in the Elgiloy strip sheet. Aging is the printed heat treatment in that sheet.
status: ground
source: elgiloy-strip-sheet
where: Physical Properties table, row Modulus of Elasticity (E), cold reduced and aged line
- benchmark: cte
label: Coefficient of thermal expansion, 20 to 200 C
value: 12.5
unit: 10-6/K
scope: material
conditions:
temperature: 20 to 200 C
unit_in_source: 12.5 [10-6/K]
method: Printed in the Physical properties table of the Studer datasheet.
status: ground
source: studer-phynox-sba011
where: Physical properties table, row Heat expansion coefficient
- benchmark: cte
label: Coefficient of thermal expansion, 20 to 300 C, wire sheet
value: 15.2
unit: um/m-C
scope: material
conditions:
temperature: 20 to 300 C
unit_in_source: 15.2 um/m-oC (20-300 oC)
method: Printed in the Physical Properties table of the Elgiloy wire sheet. The same sheet gives 8.4 microinches per inch per F for 70 to 600 F. The two values are recorded separately because the temperature ranges differ.
status: ground
source: elgiloy-wire-sheet
where: Physical Properties table, row Coefficient of Expansion, At 20oC column
- benchmark: thermal_conductivity
label: Thermal conductivity at 20 C
value: 12.5
unit: W/(m.K)
scope: material
conditions:
temperature: 20 C
unit_in_source: 12.5 W/m K
method: Printed in the Physical properties table of the Studer datasheet. The Elgiloy wire sheet prints the same 12.5 W/m-K at 20 C.
status: ground
source: studer-phynox-sba011
where: Physical properties table, row Heat conductivity
- benchmark: specific_heat
label: Specific heat capacity at 20 C
value: 450
unit: J/(kg.K)
scope: material
conditions:
temperature: 20 C
unit_in_source: 450 J/kgK
method: Printed in the Physical properties table of the Studer datasheet.
status: ground
source: studer-phynox-sba011
where: Physical properties table, row Specific heat capacity
- benchmark: electrical_resistivity
label: Specific electrical resistance at 20 C, Studer
value: 95
unit: uOhm.cm
scope: material
conditions:
temperature: 20 C
unit_in_source: 95 uOhm cm
method: Printed in the Physical properties table of the Studer datasheet. The Elgiloy wire sheet prints 99.6 uOhm.cm at 20 C, and both are recorded.
status: ground
source: studer-phynox-sba011
where: Physical properties table, row Specific resistance
- benchmark: electrical_resistivity
label: Electrical resistivity at 20 C, wire sheet
value: 99.6
unit: uOhm.cm
scope: material
conditions:
temperature: 20 C
unit_in_source: 99.6 micro ohm.cm
method: Printed in the Physical Properties table of the Elgiloy wire sheet. The Elgiloy strip sheet prints the same 99.6 micro ohm.cm at 20 C.
status: ground
source: elgiloy-wire-sheet
where: Physical Properties table, row Electrical Resistivity, At 20C column
- benchmark: ultimate_tensile_strength
label: Tensile strength, annealed wire
value: 120
value_high: 150
unit: ksi
scope: material
conditions:
temper: annealed
form: wire
heat_treatment: 2048 F (1120 C)
unit_in_source: 120 to 150 ksi (830 to 1035 MPa)
method: Typical Mechanical Properties table, Spring Applications, Elgiloy wire sheet. The MPa range is printed beside the ksi range.
status: ground
source: elgiloy-wire-sheet
where: Typical Mechanical Properties table, row Annealed
- benchmark: ultimate_tensile_strength
label: Tensile strength, spring temper wire
value: 220
value_high: 290
unit: ksi
scope: material
conditions:
temper: spring temper, no aging
form: wire
unit_in_source: 220 to 290 ksi (1515 to 2000 MPa)
method: Typical Mechanical Properties table, Spring Applications, Elgiloy wire sheet.
status: ground
source: elgiloy-wire-sheet
where: Typical Mechanical Properties table, row Spring Temper
- benchmark: ultimate_tensile_strength
label: Tensile strength, spring temper and aged wire
value: 260
value_high: 330
unit: ksi
scope: material
conditions:
temper: spring temper and aged, aged at 980 F (527 C) for 5 h after coiling
form: wire
unit_in_source: 260 to 330 ksi (1790 to 2275 MPa)
method: Typical Mechanical Properties table, Spring Applications, Elgiloy wire sheet. The aging step is printed in the same row.
status: ground
source: elgiloy-wire-sheet
where: Typical Mechanical Properties table, row Spring Temper + Aged
- benchmark: ultimate_tensile_strength
label: Tensile strength, annealed strip
value: 100
unit: ksi
scope: material
conditions:
temper: annealed per AMS 5876
form: strip
unit_in_source: 100 ksi min (690 MPa)
method: Typical Mechanical Properties table, Elgiloy strip sheet. The value is printed as a minimum.
status: ground
source: elgiloy-strip-sheet
where: Typical Mechanical Properties table, row Annealed
- benchmark: ultimate_tensile_strength
label: Tensile strength, spring temper strip, no heat treatment
value: 310
unit: ksi
scope: material
conditions:
temper: spring temper, no heat treatment
form: strip
unit_in_source: up to 310 ksi (2100 MPa)
method: Typical Mechanical Properties table, Elgiloy strip sheet. The value is printed as up to.
status: ground
source: elgiloy-strip-sheet
where: Typical Mechanical Properties table, row Spring Temper
- benchmark: ultimate_tensile_strength
label: Tensile strength, spring temper strip and aged
value: 380
unit: ksi
scope: material
conditions:
temper: spring temper after cold rolling, then aged per AMS 5876
form: strip
unit_in_source: up to 380 ksi (2600 MPa)
method: Typical Mechanical Properties table, Elgiloy strip sheet. The value is printed as up to.
status: ground
source: elgiloy-strip-sheet
where: Typical Mechanical Properties table, row Spring Temper + Aged
- benchmark: ultimate_tensile_strength
label: Tensile strength, hardened wire, over 2200
value: 2200
unit: N/mm2
scope: material
conditions:
temper: hardened by the heat treatment in the Studer datasheet
form: flat wire
unit_in_source: over 2200 N/mm2, depending on diameter
method: Printed in the Technical main features section of the Studer datasheet. The value is printed as over 2200 N/mm2 and depends on diameter, so it is a lower bound.
status: ground
source: studer-phynox-sba011
where: Technical main features, paragraph beginning Tensile strengths of over 2200 N/mm2
- benchmark: ultimate_tensile_strength
label: Tensile strength, cold rolled strip, fully hardened
value: 2500
unit: MPa
scope: material
conditions:
temper: cold rolled strip, fully hardened
form: strip
unit_in_source: up to 2500 MPa
method: Printed on the Aperam PHYNOX product page, first paragraph. The value is printed as up to.
status: ground
source: aperam-phynox
where: Product description paragraph, first sentence
- benchmark: yield_strength
label: Yield strength, cold worked
value: 1800
unit: MPa
scope: material
conditions:
temper: cold worked, no aging
unit_in_source: higher than 1800 MPa
method: Printed on the Aperam PHYNOX product page. The page gives it as higher than 1800 MPa that can be achieved by cold working alone.
status: ground
source: aperam-phynox
where: Product description paragraph beginning Yield strengths higher than 1800 MPa
- benchmark: max_service_temp
label: Suggested maximum operating temperature
value: 454
unit: C
scope: material
conditions:
temper: all listed tempers
unit_in_source: '-300 F to 850 F (-184 C to 454 C)'
method: Printed as the suggested operating range in the Typical Mechanical Properties tables of both Elgiloy sheets.
status: ground
source: elgiloy-wire-sheet
where: Typical Mechanical Properties table, Suggested Operating Conditions column
- benchmark: min_service_temp
label: Suggested minimum operating temperature
value: -184
unit: C
scope: material
conditions:
temper: all listed tempers
unit_in_source: '-300 F to 850 F (-184 C to 454 C)'
method: Printed as the suggested operating range in the Typical Mechanical Properties table of the Elgiloy wire sheet. The Elgiloy strip sheet prints the same range.
status: ground
source: elgiloy-wire-sheet
where: Typical Mechanical Properties table, Suggested Operating Conditions column
corrosion:
- environment: Seawater, crevice and pitting
headline: Virtually immune to crevice, stress corrosion and pitting in seawater, even at the highest strength levels.
effect: The Elgiloy wire sheet says that in seawater the alloy is virtually immune to crevice and stress corrosion and to pitting, even at the highest strength levels. No seawater test duration or rate is printed.
rating: low
conditions:
basis: qualitative statement, no rate printed
product: wire and strip, all strength levels
source: elgiloy-wire-sheet
where: Introduction paragraph, sentence beginning In seawater
- environment: Sour well environments, sulfide stress cracking
headline: Highly resistant to sulfide stress corrosion cracking; NACE MR0175 is an applicable specification.
effect: The Elgiloy wire sheet says the alloy is highly resistant to sulfide stress corrosion cracking and is the alloy of choice in the most demanding sour well environments. Both Elgiloy sheets list NACE MR0175 in their applicable specifications. No test figure is printed.
rating: low
conditions:
basis: qualitative statement, no test figure printed
source: elgiloy-wire-sheet
where: Introduction paragraph and Applicable Specifications row
- environment: Mineral and organic acids at room temperature
headline: Not, or only very hardly, attacked by mineral and organic acids at room temperature.
effect: The Studer SBA-011 datasheet says the alloy is not or only very hardly attacked by organic and mineral acids at room temperature, and that it outshines the best stainless steels. No acid concentration or rate is printed.
rating: low
conditions:
temperature: room temperature
basis: qualitative statement, no rate printed
source: studer-phynox-sba011
where: Technical main features, Corosion resistance paragraph
- environment: Stress corrosion cracking and hydrogen embrittlement in service
headline: Exceptional resistance to corrosion, stress corrosion cracking and hydrogen embrittlement, per the manufacturer.
effect: Aperam lists exceptional resistance to corrosion, stress corrosion cracking and hydrogen embrittlement among the most important properties of the alloy. The page prints no test data.
rating: low
conditions:
basis: manufacturer statement, no test data printed
source: aperam-phynox
where: Product text, list of complementary properties
- environment: Air during heat treatment
headline: Discolours in air; a treatment in air leaves a yellow oxide layer with no effect on mechanical properties.
effect: Studer says the material discolours in air and that this has no effect on its mechanical properties. Its thermal treatment table says a treatment in air causes a yellow oxide layer, and it recommends vacuum or argon.
rating: low
conditions:
temperature: 480 to 540 C hardening
basis: qualitative statement
source: studer-phynox-sba011
where: Heat treatment paragraph and Thermal treatment table footnote
risks:
hazards:
- text: No Phynox or Elgiloy safety data sheet was found in this run. The hazard entries use PubChem's aggregated GHS data for cobalt metal, which is a different material, and are labelled as such. The alloy is 40 percent cobalt.
ghs: []
source: pubchem-cobalt
where: Safety and Hazards, Hazards Identification, GHS Classification (signal word Danger)
- text: 'Cobalt metal, PubChem aggregated GHS data from ECHA notifications, signal word Danger: H317 may cause an allergic skin reaction, H334 may cause allergy or asthma symptoms or breathing difficulties if inhaled, H341 suspected of causing genetic defects, H350 may cause cancer, H360F may damage fertility, and H413 may cause long lasting harmful effects to aquatic life.'
ghs:
- H317
- H334
- H341
- H350
- H360F
- H413
source: pubchem-cobalt
where: Safety and Hazards, Hazards Identification, GHS Classification (aggregated notifications without percentages, cobalt CID 104730)
failure_risks:
- mode: Hardening lost or limited after welding
trigger: Welding an already hardened part
consequence: Studer says only strain hardened material can be hardened, and welded areas should not carry major mechanical stress once the material is hardened.
severity: moderate
source: studer-phynox-sba011
where: Heat treatment paragraph and Weldability paragraph
side_effects:
- text: Heat treatment in air forms a yellow oxide layer on the surface.
affects: Surface finish; the datasheet says this does not change mechanical properties.
source: studer-phynox-sba011
where: Heat treatment paragraph and Thermal treatment table footnote
handling:
- text: Anneal at 1050 C for 0.5 h and cool rapidly in air, gas or water. Stress relief cold rolled products before machining.
source: studer-phynox-sba011
where: Thermal treatment table, row Annealing; Remarks
- text: Harden at 480 to 540 C for 2 to 5 h, preferably under vacuum or in argon. Keep all heat treatments in a hydrogen free atmosphere.
source: studer-phynox-sba011
where: Thermal treatment table, rows Hardening and Protective atmosphere
- text: Machining is difficult. Studer gives a cutting speed of about 20 to 40 m/min, with moderate to strong feed.
source: studer-phynox-sba011
where: Processing, Machining table
- text: The alloy can be welded and soldered, but only strain hardened material can be hardened.
source: studer-phynox-sba011
where: Weldability paragraph
mitigations:
- text: Heat treat under vacuum or in argon, so the surface does not form the yellow oxide layer.
source: studer-phynox-sba011
where: Heat treatment paragraph
uses:
- application: mechanisms
device: Helical and shaped springs
example: Aperam lists shaped springs, helical springs and printer springs among the applications. Studer names springs and axles for the watch industry.
source: aperam-phynox
where: Applications list
- application: electronics-and-chips
device: Parts for satellite communications equipment
example: The Elgiloy strip sheet lists satellite communications equipment among its applications. It names no satellite or mission.
source: elgiloy-strip-sheet
where: Introduction paragraph, Applications sentence
- application: mechanisms
device: Watch springs and axles
example: Studer says Phynox is a popular material for springs and axles in the watch industry.
source: studer-phynox-sba011
where: Technical main features, Properties and applications paragraph
supply:
- subject: Cobalt (40 percent nominal)
producers:
- country: Congo (Kinshasa)
share_percent: 73
year: 2025
- country: Indonesia
share_percent: 14
year: 2025
critical_lists: []
recycling: 'USGS: in 2025, cobalt content of purchased scrap represented 25 percent of estimated cobalt consumption. USGS says 51 percent of cobalt consumed in the United States went into superalloys, mainly for aircraft gas turbine engines.'
substitutes:
- 'USGS: depending on the application, substitution for cobalt could result in a loss in product performance or increased cost.'
source: usgs-mcs2026-cobalt
where: Events, Trends, and Issues (Congo 73 percent, Indonesia 14 percent); Domestic Production and Use; Recycling; Substitutes
- subject: Chromium (20 percent nominal)
producers:
- country: South Africa
share_percent: 45.1
year: 2025
- country: Turkey
share_percent: 17.6
year: 2025
- country: Kazakhstan
share_percent: 13.7
year: 2025
- country: India
share_percent: 5.9
year: 2025
critical_lists: []
recycling: 'USGS: in 2025, recycled chromium in reported stainless steel scrap receipts accounted for 21 percent of apparent consumption.'
substitutes:
- 'USGS: chromium has no substitute in stainless steel, the leading end use, or in superalloys, the major strategic end use.'
source: usgs-mcs2026-chromium
where: World Mine Production and Reserves table, 2025e column (South Africa 23,000 t, Turkey 9,000 t, Kazakhstan 7,000 t, India 3,000 t, world total 51,000 t). Shares are calculated by Space Mushroom from those tonnages, since USGS does not print them. Recycling; Substitutes.
- subject: Molybdenum (7 percent nominal)
producers:
- country: China
share_percent: 37.3
year: 2025
- country: Chile
share_percent: 16.2
year: 2025
- country: Peru
share_percent: 15
year: 2025
- country: Mexico
share_percent: 6.5
year: 2025
critical_lists: []
recycling: 'USGS: molybdenum is recycled as a component of catalysts, ferrous scrap and superalloy scrap. The USGS summary gives no recycled share for molybdenum.'
substitutes:
- 'USGS: there is little substitution for molybdenum in its major application in steels and cast irons. Potential substitutes in alloy steels include boron, chromium, niobium and vanadium.'
source: usgs-mcs2026-molybdenum
where: Events, Trends, and Issues (China, Chile, United States, Peru and Mexico account for 90 percent of world production); World Mine Production and Reserves table, 2025e column (China 97,000 t, Chile 42,000 t, Peru 39,000 t, Mexico 17,000 t, world total 260,000 t). Shares are calculated by Space Mushroom from those tonnages. Recycling; Substitutes.
- subject: Nickel (16 percent nominal)
producers:
- country: Indonesia
share_percent: 66.7
year: 2025
- country: Philippines
share_percent: 6.9
year: 2025
- country: Russia
share_percent: 5.1
year: 2025
critical_lists: []
recycling: 'USGS: most secondary nickel was in the form of nickel content of stainless steel scrap, and most recycled nickel was used to make new alloys.'
substitutes:
- 'USGS: low-nickel, duplex or ultrahigh-chromium stainless steels have been substituted for austenitic grades in some applications. Titanium alloys can substitute for nickel-base alloys in corrosive environments.'
source: usgs-mcs2026-nickel
where: World Mine Production and Reserves table, 2025e column (Indonesia 2,600,000 t, Philippines 270,000 t, Russia 200,000 t, world total 3,900,000 t). Shares are calculated by Space Mushroom from those tonnages. Recycling; Substitutes. Countries with smaller shares are left out.
documents:
- title: Studer-Biennaform, Phynox flat wire technical data sheet SBA-011, edition 2023/10
type: datasheet
url: https://www.studersa.com/media/cms/Legierungen%20/%20Tech-Sheets/SBA%20-%20Tech%20Sheet%20/%20Werkstoffe/sba-011-tech-sheet-phynox.pdf
year: 2023
- title: Elgiloy Specialty Metals, Elgiloy wire products data sheet
type: datasheet
url: https://www.combmet.com/wp-content/uploads/2023/05/Wire-Elgiloy-Alloy.pdf
- title: Elgiloy Specialty Metals, Elgiloy strip products data sheet (dated 4/10/17)
type: datasheet
url: https://www.combmet.com/wp-content/uploads/2023/02/Strip-Elgiloy-Alloy-1.pdf
year: 2017
- title: Aperam, PHYNOX product page with datasheet link
type: datasheet
url: https://www.aperam.com/product/phynox/
- title: 'PubChem: Cobalt (CID 104730), GHS classification summary'
type: database
url: https://pubchem.ncbi.nlm.nih.gov/compound/Cobalt
- title: 'USGS Mineral Commodity Summaries 2026: Cobalt'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-cobalt.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: Molybdenum'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-molybdenum.pdf
year: 2026
- title: 'USGS Mineral Commodity Summaries 2026: Nickel'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
year: 2026
- title: 'Wikipedia: Elgiloy, composition, specifications and trade names'
type: database
url: https://en.wikipedia.org/wiki/Elgiloy
gaps:
- No Phynox or Elgiloy safety data sheet was found. The hazard entries use the PubChem cobalt summary, which is for cobalt metal, not this alloy.
- 'Melting point or melting range: not printed in any source read in this run.'
- 'Elongation and hardness: not printed in the Studer or Elgiloy datasheets read. The Goodfellow comparison article prints values for these, but its tables cite no source, so they were not used.'
- 'Corrosion rates in mils per year or mm per year, and pitting or crevice potentials: not printed in any source read. The corrosion ratings are the assistant''s grouping of the printed wording, not measured values.'
- UNS R30008 is left out. Aperam and Studer list it with R30003, but it is a separate grade (ASTM F1058 grade 2) with its own composition, so it is not an alias.
- 'Iron: Aperam prints 15 percent as the nominal value, while Studer and the Elgiloy sheets print iron as the balance. Both are recorded in the recipe.'
- 'Young''s modulus at 20 C: the Studer datasheet prints 215 GPa for flat wire and the Elgiloy wire sheet prints 190 GPa for wire. Both are kept with their own source.'
- 'Electrical resistivity at 20 C: Studer prints 95 uOhm.cm and the Elgiloy sheets print 99.6 uOhm.cm. Both are kept.'
- 'Beryllium: the Elgiloy wire sheet gives a maximum of 0.1 percent, the strip sheet gives 0.10 percent, and the Studer table gives 0.001 percent. The values conflict, so beryllium is not listed in the recipe.'
- Wikipedia gives an iron range of 11.3 to 20.5 percent that does not match the datasheets and is not used. Wikipedia is used for composition and trade names only.
- The Matthey Phynox datasheet link returned an error and was not read. The Springer article on Elgiloy corrosion is behind a paywall and was not read.
- The ASTM F1058 text itself was not read. The standard is cited only as a specification listed in the datasheets.
- No ASTM, AMS or EN standard gives per-grade composition limits in the sources read beyond the datasheet ranges.
- Critical-mineral list status for cobalt, chromium, molybdenum and nickel is not printed in the USGS text read, so critical_lists is empty.
- No flight, spacecraft or launch-vehicle record, and no radiation, outgassing, atomic oxygen or vacuum data, was found in any source read in this run.
- No image with a checked licence was opened, so the profile has no media entry.
sources:
studer-phynox-sba011:
title: Studer-Biennaform (Notz Metal), Phynox flat wire technical data sheet, material 2.4711, SBA-011
id: edition 2023/10, printed on the sheet
url: https://www.studersa.com/media/cms/Legierungen%20/%20Tech-Sheets/SBA%20-%20Tech%20Sheet%20/%20Werkstoffe/sba-011-tech-sheet-phynox.pdf
year: 2023
kind: datasheet
license: Manufacturer technical data sheet, informative only (cited, not reproduced)
elgiloy-wire-sheet:
title: Elgiloy Specialty Metals, Specialty Metals Wire Products, Elgiloy (UNS R30003, W.Nr 2.4711)
url: https://www.combmet.com/wp-content/uploads/2023/05/Wire-Elgiloy-Alloy.pdf
kind: datasheet
license: Manufacturer data sheet (cited, not reproduced)
elgiloy-strip-sheet:
title: Elgiloy Specialty Metals, Specialty Metals Strip Products, Elgiloy (UNS R30003, W.Nr 2.4711)
id: sheet dated 4/10/17
url: https://www.combmet.com/wp-content/uploads/2023/02/Strip-Elgiloy-Alloy-1.pdf
year: 2017
kind: datasheet
license: Manufacturer data sheet (cited, not reproduced)
aperam-phynox:
title: Aperam, PHYNOX product page (grade data, composition, applications)
url: https://www.aperam.com/product/phynox/
kind: web
license: Manufacturer web page (cited, not reproduced)
wiki-elgiloy:
title: Elgiloy, Wikipedia
url: https://en.wikipedia.org/wiki/Elgiloy
kind: database
license: CC BY-SA (cited, not reproduced); used for composition ranges, specifications and trade names only
pubchem-cobalt:
title: PubChem, Cobalt (CID 104730), GHS classification (aggregated ECHA notifications)
url: https://pubchem.ncbi.nlm.nih.gov/compound/Cobalt
kind: database
license: PubChem, public domain (cited, not reproduced)
usgs-mcs2026-cobalt:
title: 'Mineral Commodity Summaries 2026: Cobalt (U.S. Geological Survey)'
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-cobalt.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-mcs2026-chromium:
title: 'Mineral Commodity Summaries 2026: Chromium (U.S. Geological Survey)'
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-mcs2026-molybdenum:
title: 'Mineral Commodity Summaries 2026: Molybdenum (U.S. Geological Survey)'
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-molybdenum.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-mcs2026-nickel:
title: 'Mineral Commodity Summaries 2026: Nickel (U.S. Geological Survey)'
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
year: 2026
kind: report
license: public domain (USGS)
license: CC-BY-4.0
updated: '2026-10-26'
review:
status: draft
method: assistant
checked_values: 22
unreachable: 2
caveats: 4
note: 'Values were read by an AI assistant on 2026-10-26 from the Studer SBA-011 datasheet, the Elgiloy wire and strip data sheets, the Aperam PHYNOX page, Wikipedia, PubChem and USGS MCS 2026. Caveats: the Studer and Elgiloy modulus and resistivity values differ and both are recorded; the hazard data are for cobalt metal; the corrosion ratings are assistant groupings of qualitative wording; the Matthey datasheet link was unreachable.'
story:
recipe:
line: Phynox is a cobalt-base austenitic alloy of cobalt, chromium, nickel, molybdenum and iron, with manganese and a little carbon. Aperam gives the nominal composition as Co 40, Cr 20, Ni 16, Fe 15 and Mo 7 (weight percent). Studer describes the product as annealed at 1050 C and then cold worked and age hardened at 480 to 540 C for 2 to 5 h under vacuum or argon. The sources read here do not describe how the alloy is melted.
parts:
- name: Cobalt
symbol: Co
share_percent: 40
role: Main element. Aperam gives 40 percent as the nominal value, and Studer says the alloy contains 40 percent cobalt.
- name: Chromium
symbol: Cr
share_percent: 20
role: Major element for corrosion resistance. The sources give it no separate role.
- name: Nickel
symbol: Ni
share_percent: 16
role: Austenite former. Studer gives 16 percent; the Elgiloy sheets give a range of 14 to 18 percent.
- name: Molybdenum
symbol: Mo
share_percent: 7
role: Alloying element. Studer gives 7 percent; the Elgiloy sheets give a range of 6 to 8 percent.
- name: Iron
symbol: Fe
share_percent: 15
role: Nominal value from Aperam. Studer and the Elgiloy sheets list iron as the balance.
- name: Manganese
symbol: Mn
role: Alloying element. The Elgiloy strip sheet prints a range only, and no nominal value is printed.
- name: Carbon
symbol: C
role: Minor element. The Elgiloy sheets print a maximum only.
risk_groups:
- title: For people
lead: No Phynox safety data sheet was found. The hazard data here are PubChem's cobalt summary, so they describe cobalt metal rather than this alloy.
level: 1
verdict: Unverified for this alloy
points:
- label: Sensitisation
line: PubChem's aggregated cobalt data lists H317 and H334, which mean an allergic skin reaction and allergy or breathing difficulties if inhaled.
- label: Carcinogenicity and fertility
line: The same summary lists H350 (may cause cancer), H360F (may damage fertility) and H341 (suspected of causing genetic defects).
- label: Dust and fume
line: No Phynox-specific fume statement was in the sources read. Studer says machining is difficult and slow.
- title: If it fails
lead: The failure routes in the sources are about welding after hardening and about reheating. The sources report no service failure in space.
points:
- label: Welding after hardening
line: Only strain hardened material can be hardened, so welded areas should not carry major stress after hardening.
- label: Corrosion
line: The sources give qualitative corrosion resistance only, with no measured rate in seawater, acid or sour service.
- title: Handling and storage
points:
- label: Heat treatment
line: Anneal at 1050 C for 0.5 h, then harden at 480 to 540 C for 2 to 5 h, preferably under vacuum or argon.
- label: Stress relief
line: Stress relieve cold rolled products before machining.
- label: Machining
line: Machining is difficult. Use slow cutting speeds of about 20 to 40 m/min and moderate to strong feeds.
why: Phynox is a non-magnetic cobalt alloy that the manufacturers describe as strong, tough and corrosion resistant. Aperam says cold rolled strip reaches up to 2500 MPa and that cold work alone can give more than 1800 MPa yield strength. The listed uses are springs, diaphragms, electrical apparatus, aerospace equipment, surgical implants and pacemaker electrodes. The sources read here give no spacecraft flight record.
uses:
- where: Springs
line: Aperam lists helical, shaped and printer springs among the applications.
- where: Satellite communications equipment
line: The Elgiloy strip sheet lists satellite communications equipment among its applications, without naming a mission.
- where: Watch springs and axles
line: Studer says Phynox is a popular material for springs and axles in the watch industry.
can_do:
- label: Strength in cold rolled strip
value: 2500 MPa
benchmark: ultimate_tensile_strength
line: Aperam gives up to 2500 MPa for cold rolled strip in the fully hardened condition.
- label: Stiffness in the wire sheet
value: 190 GPa
benchmark: elastic_modulus
line: The Elgiloy wire sheet gives 190 GPa at 20 C. Studer gives 215 GPa for flat wire at the same temperature.
- label: Operating range
value: '-184 to 454 C'
benchmark: max_service_temp
line: Both Elgiloy sheets give a suggested operating range of -300 to 850 F (-184 to 454 C) for all listed tempers.
compare: Phynox and Elgiloy are the same alloy under two trade names. In the Elgiloy wire sheet the annealed tensile range is 120 to 150 ksi, and the spring temper and aged range is 260 to 330 ksi. The Elgiloy strip sheet gives up to 380 ksi for spring temper strip that is aged. The sheets come from one manufacturer, and the datasheet values are typical, not minimums, so read them as examples, not a ranking against other alloys.
compare_rows:
- label: Density
benchmark: density
- label: Thermal conductivity
benchmark: thermal_conductivity
- label: Thermal expansion
benchmark: cte
handling:
- Anneal at 1050 C for 0.5 h, then harden at 480 to 540 C for 2 to 5 h under vacuum or argon.
- Welding and soldering are possible, but welded areas should not carry major stress after hardening.
- Machining is difficult, so use slow speeds and stress relieve cold rolled products before machining.
good_for:
- 'Springs and diaphragms: up to 2500 MPa in cold rolled strip, per Aperam.'
- 'Non-magnetic parts: Studer says the alloy can be considered non-magnetic over the whole temperature range.'
- 'Seawater and sour wells: the Elgiloy sheets say it is virtually immune to crevice and pitting attack in seawater and highly resistant to sulfide stress cracking.'
watch_out:
- 'Heat treatment in air: the surface forms a yellow oxide layer.'
- 'No measured corrosion rates: the corrosion ratings rest on qualitative statements.'
- 'Conflicting values: modulus and resistivity differ between the Studer and Elgiloy sheets.'
- No Phynox-specific SDS, no flight record and no measured elongation or hardness were found in this run.
verdict: Phynox is a strong, non-magnetic cobalt-base spring alloy, and the manufacturers' data support its use in springs, diaphragms and thin strip. The sources read here give qualitative corrosion resistance, no measured corrosion rates and no spacecraft flight record.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
| # | Source | Type | Year | Used for |
|---|---|---|---|---|
| Studer-Biennaform (Notz Metal), Phynox flat wire technical data sheet, material 2.4711, SBA-011 | datasheet | 2023 | 16 values | |
| Elgiloy Specialty Metals, Specialty Metals Wire Products, Elgiloy (UNS R30003, W.Nr 2.4711) | datasheet | 11 values | ||
| Elgiloy Specialty Metals, Specialty Metals Strip Products, Elgiloy (UNS R30003, W.Nr 2.4711) | datasheet | 2017 | 6 values | |
| Aperam, PHYNOX product page (grade data, composition, applications) | web | 5 values | ||
| Elgiloy, Wikipedia | database | 0 values | ||
| PubChem, Cobalt (CID 104730), GHS classification (aggregated ECHA notifications) | database | 2 values | ||
| Mineral Commodity Summaries 2026: Cobalt (U.S. Geological Survey) | report | 2026 | 1 value | |
| Mineral Commodity Summaries 2026: Chromium (U.S. Geological Survey) | report | 2026 | 1 value | |
| Mineral Commodity Summaries 2026: Molybdenum (U.S. Geological Survey) | report | 2026 | 1 value | |
| Mineral Commodity Summaries 2026: Nickel (U.S. Geological Survey) | report | 2026 | 1 value |