Commercially pure titanium, Grade 7 (UNS R52400, Ti-0.15Pd) CP Ti Grade 7

Unalloyed titanium with 0.12 to 0.25 % palladium, UNS R52400 (ASTM Grade 7): maximum limits on O, Fe, C, N and H, titanium the balance

Also known as UNS R52400, EN 3.7235, ASTM B265, ASTM B863, ASME SB-265, Titanium Grade 7 · 1 more

Commercially pure (CP) titanium Grade 7, UNS R52400, is unalloyed titanium with 0.12 to 0.25 % palladium added (ASTM B265 Table 2).

11 sources · Updated 2026-10-26 · CC BY 4.0

Evidence level

2 of 5

Lab-measured

Strength

> 345 MPa

Ductility

> 20 %

Stiffness

112 GPa

Recipe, share of the weight

  • Ti balance (the rest)Titanium
  • Pd 0.12 to 0.25 %Palladium
  • O maximum 0.25 %Oxygen
  • Fe maximum 0.3 %Iron
  • C maximum 0.08 %Carbon
  • N maximum 0.03 %Nitrogen
  • H maximum 0.015 %Hydrogen

Best for

Chemical processing and hot chloride or acid service where crevice corrosion is the main concern and Grade 2 is not enough (ATI corrosion data sheet; Elgiloy datasheet)

Weakest at

Strength: 345 MPa minimum tensile, the same as Grade 2 and well below Ti-6Al-4V. Its crevice limit depends on pH and temperature, and no Grade 7 test at pH 1 or below was read in this run

Risk at a glance

  • People Low. Solid: no class. Powder and swarf: flammable
  • If it fails Moderate. Crevice attack in hot chloride or seawater above the stated limit
  • Corrosion Low. Grade 7 resisted stress corrosion cracking and pitting in near-anaerobic seawater up to 200 C.

Quick facts: CP Ti Grade 7

Key properties of CP Ti Grade 7
PropertyValueBasis
Density4.51 g/cm³1 sourced value
Yield strengthat least 275 MPa1 sourced value
Tensile strength345 to 448 MPa3 sourced values across conditions
Young's modulus112 GPa1 sourced value
Thermal conductivity21.8 W/(m·K)1 sourced value
Thermal expansion (CTE)9.7 ppm/K1 sourced value
Electrical resistivity5.3e-7 Ω·m1 sourced value
Maximum service temperature540 °C1 sourced value

What is the density of Commercially pure titanium, Grade 7?

Commercially pure titanium, Grade 7 has a density of 4.51 g/cm³. The source and test conditions are listed in the properties table on this page.

What is the thermal conductivity of Commercially pure titanium, Grade 7?

Commercially pure titanium, Grade 7 has a thermal conductivity of 21.8 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 Commercially pure titanium, Grade 7?

Commercially pure titanium, Grade 7 has a coefficient of thermal expansion of 9.7 ppm/K. The source and test conditions are listed in the properties table on this page.

What is the yield strength of Commercially pure titanium, Grade 7?

Commercially pure titanium, Grade 7 has a yield strength of at least 275 MPa. The source and test conditions are listed in the properties table on this page.

What is the tensile strength of Commercially pure titanium, Grade 7?

Commercially pure titanium, Grade 7 has a tensile strength of 345 to 448 MPa. 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 are the other names and codes for Commercially pure titanium, Grade 7?

Commercially pure titanium, Grade 7 is also written as UNS R52400, EN 3.7235, ASTM B265, ASTM B863, ASME SB-265, Titanium Grade 7. Each code is printed in the source listed beside it in the designations table.

What is Commercially pure titanium, Grade 7 used for?

Uses recorded in the sources include Heat exchangers, condensers and chemical process piping; Production equipment components.

Why it exists

Grade 7 is the palladium-alloyed version of the most common unalloyed titanium grade. It keeps Grade 2's moderate strength, ductility and weldability, and the small palladium addition gives it better crevice and acid resistance. ATI says the palladium-alloyed grades typically do not crevice-corrode below 250 C at pH above 1, against 80 C for unalloyed grades 1 to 4. It is chosen when crevice corrosion in chloride or acid service is the main concern and strength is secondary.

Where it's used

Chemical processing

Elgiloy lists chemical processing among the industries it supplies Grade 7 strip to. Bozo Metal lists reactors, storage tanks, acid pipelines and heat-exchanger tubing as typical uses. The Bozo Metal page is a supplier listing with no test data.

Seawater and hot chloride service

Titanium Industries says Grade 7 is viable for significantly better crevice corrosion resistance above 260 C in seawater, with Grade 12 as a lower-cost alternative.

Recipe

Unalloyed titanium with 0.12 to 0.25 % palladium, UNS R52400 (ASTM Grade 7): maximum limits on O, Fe, C, N and H, titanium the balance

Unalloyed titanium with 0.12 to 0.25 % palladium, the only deliberate addition. ASTM B265 limits the Grade 7 composition to maximum oxygen, iron, carbon, nitrogen and hydrogen, with titanium as the balance. Wikipedia describes Grade 7 as similar to Grade 2 with palladium added. Process routes are not described in the sources fetched for this profile.

What CP Ti Grade 7 is made of
IngredientShare of the weightWhat it does
Titanium Ti balance (the rest) Base metal. Gives the low density and the oxide-film corrosion resistance.
Palladium Pd 0.12 to 0.25 % Deliberate addition. ATI and Elgiloy credit it with better crevice and acid resistance than unalloyed CP grades.
Oxygen O maximum 0.25 % Interstitial impurity with a maximum limit.
Iron Fe maximum 0.3 % Impurity with a maximum limit.
Carbon C maximum 0.08 % Interstitial impurity with a maximum limit.
Nitrogen N maximum 0.03 % Interstitial impurity with a maximum limit.
Hydrogen H maximum 0.015 % Interstitial impurity with a maximum limit.

Weight shares are as printed in the sources.

What it can do

Strength

> 345 MPa

measured

Minimum tensile strength 345 MPa and minimum 0.2 % yield strength 275 MPa for strip, sheet and plate (ASTM B265). Typical annealed strip tensile is 448 MPa (Elgiloy).

Ductility

> 20 %

measured

Minimum elongation 20 % (ASTM B265, 2 in or 50 mm gauge). Minimum reduction of area 30 % for bar, tube and wire (ATI).

Stiffness

112 GPa

measured

Elastic modulus 112 GPa at 20 C (Elgiloy).

Corrosion

Palladium-alloyed; typically no crevice corrosion below 250 C at pH above 1 (ATI). Crevice attack is reported for Grade 2 at 80 C in near-anaerobic seawater (Pang and Blackwood), but no Grade 7 crevice temperature is printed in that abstract.

How it compares

Grade 7 is the palladium-alloyed version of Grade 2 ([Grade 2](/materials/titanium-grade-2)). Its strength is the same as Grade 2 (345 MPa minimum tensile, 275 MPa minimum yield, ASTM B265), and its density is 4.51 g/cm3 (Elgiloy and ATI). Its elastic modulus is 112 GPa at 20 C (Elgiloy). The palladium is the reason to choose Grade 7 over Grade 2 in crevice-prone service. Both are far weaker than [Ti-6Al-4V](/materials/ti-6al-4v).

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.

Benchmarks
MeasurementCP Ti Grade 7CP Ti Grade 2Ti-6Al-4VTi-6Al-4V ELITi-3Al-2.5V (Grade 9)TiAlBeta 3Ti Grade 11Ti Gr 12CP Ti Grade 3Ti minor alloys
Thermal behavior and safety
Thermal conductivity21.79 W/m-K422 W/(m·K)6.7 W/(m K)6.6 W/(m K)no datano datano data21.79 W/(m·K)19.02 W/(m·K)151.2 Btu-in/(hr·ft²·°F)46.8 BTU-in/hr-ft2-°F
Physical and electrical
Density4.51 g/cm³14.51 g/cm³4.43 g/cm³4.42 g/cm³4.48 g/cm³3.8 g/cm³5.07 g/cm³4.51 g/cm³4.51 g/cm³4.51 g/cm³4.54 g/cm³
Electrical resistivity53.3 µΩ·cm6no datano data1.68 μΩ·mno datano datano data53.3 μΩ·cm52 µΩ·cmno datano data
Other measurements
Elastic modulus112 GPa2103 GPa113.8 GPa107 to 122 GPa91 GPa168 GPa82 GPa112 GPa103 GPa103 GPa15000 ksi
Modulus of rigidity41 GPa3no datano data41 to 45 GPa44 GPano datano data41 GPano datano datano data
Coefficient of thermal expansion9.7 µm/m-°C5no data8.6 10^-6 /°C9 10^-6 /°Cno datano datano data9.7 μm/(m·°C)9.54 10^-6/°C8.6 10-6/°C9.7 ppm/K
Tensile strength, minimum (strip, sheet and plate)> 345 MPa7> 345 MPano data828 MPa> 620 MPa422 MPa1000 MPa> 240 MPa> 483 MPa> 450 MPa< 175 ksi
Yield strength, 0.2 % offset, minimum (strip, sheet and plate)> 275 MPa8> 275 MPa830 MPa759 MPa> 483 MPa326 MPa965 MPa> 138 MPa> 345 MPa> 380 MPa< 186 ksi
Elongation, minimum (strip, sheet and plate)> 20 %9> 20 %10 %10 %> 15 %1.7 %7 %> 24 %> 18 %> 18 %< 10 %
Tensile strength, minimum (bar, seamless tube, pipe and wire)> 345 MPa10> 345 MPano data828 MPa> 620 MPa422 MPa1000 MPa> 240 MPa> 483 MPa> 450 MPa< 175 ksi
Reduction of area, minimum (bar, seamless tube, pipe and wire)> 30 %11> 35 %no data41.5 %no datano datano datano datano data> 35 %no data
Tensile strength, typical (annealed strip)448 MPa12> 345 MPano data828 MPa> 620 MPa422 MPa1000 MPa> 240 MPa> 483 MPa> 450 MPa< 175 ksi
Suggested maximum operating temperature< 540 °C13no datano datano datano datano data288 °C540 °C600 °Fno datano data
Suggested minimum operating temperature> -184 °C14no datano datano datano datano datano data-184 °Cno datano datano data

Why choose it, and why not

Good for

  • Crevice-prone chloride or acid service above the range where Grade 2 is safe (ATI, Titanium Industries).
  • Forming and welding of sheet, plate and tube where ductility and weldability matter more than strength (Elgiloy, ASTM B265).
  • Chemical process equipment: reactors, heat exchangers and acid piping (Elgiloy, Bozo Metal).

Watch out for

  • Lower strength than Ti-6Al-4V: 345 MPa minimum tensile (see the Ti-6Al-4V profile).
  • Crevice limit is a manufacturer statement with no test conditions; the ATI limit applies only above pH 1.
  • Crevice attack is reported for Grade 2 at 80 C in near-anaerobic seawater; no comparable Grade 7 result is printed in the abstract read.
  • Powder and swarf are a flammable-solid fire hazard (PubChem).

CP titanium Grade 7 is Grade 2 with palladium added for better crevice and acid resistance. Its strength is the same modest 345 MPa minimum tensile, so it is a corrosion-service material, not a structural alloy. Pick it over Grade 2 where crevice attack in hot chloride or acid is the main risk, and verify the pH and temperature limits for the specific service.

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.

Other names and standards
SystemCodes
UNSR52400
EN3.7235
ASTMB265 (strip, sheet and plate), B863 (rod and wire)
ASMESB-265 (strip, sheet and plate)
NameTitanium Grade 7
Trade nameATI CP Grade 7 Titanium

Notes

The method, full conditions and any caveat for the numbered rows above.

Notes for the numbered rows
#MeasurementMethodConditionsCaveat
1DensityPrinted as 4.51 g/cm3 in the Physical Properties block of the Elgiloy strip datasheet (0.163 lb/in3 at 70 F). The ATI product page prints the same 4.51 g/cm3 for Grade 7 bar, tube, sheet and plate.form strip, sheet and plate (Elgiloy strip datasheet)condition at 20 C (At 20oC column)—
2Elastic modulusPrinted as 112 GPa at 20 C in the Physical Properties block of the Elgiloy strip datasheet (16.3 x 10^3 ksi at 70 F).form strip (Elgiloy strip datasheet)loading modulus of elasticity (E)condition at 20 C—
3Modulus of rigidityPrinted as 41 GPa at 20 C (modulus of rigidity, G) in the Physical Properties block of the Elgiloy strip datasheet.form strip (Elgiloy strip datasheet)condition at 20 C—
4Thermal conductivityPrinted as 21.79 W/m-K in the Physical Properties block of the Elgiloy strip datasheet (12.60 Btu-in/ft hr F at 70 F). The value is recorded in the unit printed.form strip (Elgiloy strip datasheet)temperature 20 C (At 20oC column)—
5Coefficient of thermal expansionPrinted as 9.7 μm/m-oC over 20 to 500 C in the Physical Properties block of the Elgiloy strip datasheet (5.4 microinches/in-F over 70 to 932 F). The unit is written as printed.form strip (Elgiloy strip datasheet)temperature range 20 to 500 Cunit in source μm/m-oC—
6Electrical resistivityPrinted as 53.3 μ ohm.cm at 20 C in the Physical Properties block of the Elgiloy strip datasheet (21 μ ohm.in at 70 F).form strip (Elgiloy strip datasheet)condition at 20 Cunit in source μ ohm.cm—
7Tensile strength, minimum (strip, sheet and plate)Minimum in Table 1 (Tensile Requirements) of the ASTM B265-08b copy, Grade 7 row, with 50 ksi printed beside 345 MPa.form strip, sheet and plate (ASTM B265 product)condition as specified for Grade 7 in ASTM B265-08b Table 1minimum yes—
8Yield strength, 0.2 % offset, minimum (strip, sheet and plate)Minimum in Table 1 of the ASTM B265-08b copy, Grade 7 row, with 40 ksi printed beside 275 MPa. The same row prints a maximum of 450 MPa (65 ksi), which is not recorded here. The ATI page prints 276 MPa for bar; the ASTM value is used.form strip, sheet and plate (ASTM B265 product)offset 0.2 %minimum yes—
9Elongation, minimum (strip, sheet and plate)Minimum elongation in Table 1 of the ASTM B265-08b copy, Grade 7 row.form strip, sheet and plate (ASTM B265 product)gauge 2 in or 50 mmminimum yes—
10Tensile strength, minimum (bar, seamless tube, pipe and wire)Printed as 50 ksi min and 345 MPa min for the bar, seamless tube, seamless pipe and wire product, metallurgical condition 1300 F anneal, on the ATI Grade 7 product page.form bar, seamless tube, seamless pipe and wire (ATI product page)condition 1300 F annealminimum yes—
11Reduction of area, minimum (bar, seamless tube, pipe and wire)Printed as Reduction in Area 30 % Min on the ATI Grade 7 product page for the same bar, tube and wire row. reduction_of_area is not in the canonical list, so a snake_case name is used (see gaps).form bar, seamless tube, seamless pipe and wire (ATI product page)condition 1300 F annealminimum yes—
12Tensile strength, typical (annealed strip)Printed as 65 ksi (448 MPa) typ in the Typical Mechanical Properties table of the Elgiloy strip datasheet, Annealed row, heat treatment 1290 F. The datasheet's minimum for the same row is 50 ksi (345 MPa), recorded above from ASTM B265.form strip (Elgiloy strip datasheet)heat treatment 1290 F annealbasis typical, not a minimum—
13Suggested maximum operating temperaturePrinted as 1000 F (540 C) as the upper end of Suggested Operating Conditions on the Elgiloy strip datasheet. It is a supplier suggestion, not a tested service limit.form strip (Elgiloy strip datasheet)basis suggested operating condition printed by the supplier—
14Suggested minimum operating temperaturePrinted as -300 F (-184 C) as the lower end of Suggested Operating Conditions on the Elgiloy strip datasheet. It is a supplier suggestion, not a tested service limit.form strip (Elgiloy strip datasheet)basis suggested operating condition printed by the supplier—

Corrosion and compatibility

What happens when it meets other materials and environments.

Corrosion and compatibility
EnvironmentConcernWhat happens
Near-anaerobic seawater up to 200 C, with and without CO2 low Grade 7 resisted stress corrosion cracking and pitting in near-anaerobic seawater up to 200 C.1
Crevice corrosion in palladium-alloyed CP titanium low Palladium-alloyed CP grades, including Grade 7, typically do not crevice-corrode below 250 C at pH above 1.2
Hot seawater (crevice corrosion, above about 260 C) low Grade 7 is named for significantly better crevice corrosion resistance above 260 C in seawater.3
Reducing and non-oxidising acids low The palladium addition is described as giving Grade 7 extreme resistance to acid corrosion.4
Corrosion details
#EnvironmentDetailsTest conditions
1 Near-anaerobic seawater up to 200 C, with and without CO2 Pang and Blackwood tested Grades 2, 5 and 7 in near-anaerobic seawater (below 1 ppm oxygen) up to 200 C, with and without CO2. The abstract says all three grades resist stress corrosion cracking and pitting. It names crevice corrosion only for Grades 2 and 5 (at 80 C and 200 C), so no crevice temperature for Grade 7 is printed in the abstract. electrolyte seawater, near-anaerobic (below 1 ppm oxygen)temperature up to 200 CCO2 tested with and without CO2
2 Crevice corrosion in palladium-alloyed CP titanium ATI says palladium-alloyed CP titanium (grades 7, 11, 16 and 17) is more resistant to crevice corrosion than unalloyed CP grades and typically does not suffer crevice corrosion below 250 C at pH greater than 1. The same sheet says unalloyed CP grades 1 to 4 typically do not crevice-corrode below 80 C at any pH. The sheet prints no test conditions for these statements. temperature below 250 CpH greater than 1basis manufacturer statement; no test conditions printed
3 Hot seawater (crevice corrosion, above about 260 C) Titanium Industries says that for significantly better crevice corrosion resistance at temperatures above 500 F (260 C), Titanium Grade 7 is viable, with Grade 12 as a lower-cost alternative. The statement is a supplier comparison; no test data are printed. temperature above 260 C (500 F)basis supplier statement; no test conditions printed
4 Reducing and non-oxidising acids The Elgiloy strip datasheet says Grade 7 is extremely resistant to corrosion, especially from acids, because of the palladium addition, and lists chemical processing among its industries. The datasheet prints no acid, concentration or temperature. basis manufacturer statement; no acid, concentration or temperature printed

Risks and side effects

Hazards to people, what happens when a cell overheats, and how the material is handled and stored.

For people

The solid metal is not hazard-classed in the sources fetched here. PubChem gives titanium a flammable-solid classification (H228), which applies to powder and swarf.

Solid metal
Sheet, plate, bar, tube and wire are covered by the ATI and Elgiloy product sheets, which carry no hazard classification.
Powder and swarf
PubChem gives H228 (flammable solid) from aggregated reports. Treat powder and swarf as a fire hazard.

Test details
The original wording and numbers from the sources, for readers who want them.

Failure risks

Failure risks
FailureTrigger and consequence
Crevice attack in hot chloride or seawater above the stated limitmoderate severityTight crevices in chloride service above about 250 C, or at pH 1 or belowLocal attack inside the crevice. ATI's limit applies only above pH 1, and no Grade 7 test at pH 1 or below is printed in the sources read.
Crevice corrosion of a related palladium-free CP grade in hot seawatermoderate severityTight crevices in near-anaerobic seawater at 80 C and abovePang and Blackwood report this for Grade 2 at 80 C, which is why Grade 7 is chosen for hotter crevice service. This is not a Grade 7 result.
Fire from titanium powder or swarfmoderate severityHandling fine powder or swarfPubChem gives H228 (flammable solid) from aggregated reports. Sheet, bar and tube are not classed in the sources read.

Handling and storage

  • Bend test radii in ASTM B265 Table 1 for Grade 7 are 2T for thickness under 0.070 in and 2.5T for 0.070 to 0.187 in.
  • Elgiloy describes Grade 7 as having excellent welding and fabrication properties, with physical and mechanical properties similar to Grade 2.

Supply and geography

How common the raw materials are and where they come from.

Titanium sponge (feedstock for titanium mill products, including Grade 7)

The USGS 2026 titanium summary fetched for this profile gives no crustal abundance or resource tonnage. It refers to a separate titanium mineral concentrates chapter.

Top producers (2025)
China 70.3%, Japan 14.3%, Russia 6.8%, Kazakhstan 4.3%, Saudi Arabia 3.2%