Unalloyed commercially pure titanium is divided into four distinct grades, numbered 1 through 4. The grade is related to the required corrosion resistance, ductility, and strength. Properties range from grade 1, with the highest corrosion resistance and formability but the lowest strength, through grade 4, which offers the highest strength with moderate ductility.
Chemical composition
| Element |
Grade 1 |
Grade 2 UNS R50400 % |
Grade 3 UNS R50550 % |
Grade 4 UNS R50700 % |
|
Nitrogen |
0.03 max | 0.03 max | 0.05 max | 0.05 max |
|
Carbon |
0.08 max | 0.08 max | 0.08 max | 0.08 max |
|
Hydrogen |
0.015 max | 0.015 max | 0.015 max | 0.015 max |
|
Iron |
0.20 max | 0.30 max | 0.30 max | 0.50 max |
|
Oxygen |
0.18 max | 0.25 max | 0.35 max | 0.40 max |
|
Titanium |
Balance | Balance | Balance | Balance |
Mechanical properties
|
Grade |
Ultimate tensile |
Yield strength*, min |
Elongation** min, % |
| 1 |
240 MPa [35 ksi] |
170 MPa [25 ksi] | 24 |
| 2 |
345 MPa [50 ksi] |
275 MPa [40 ksi] | 20 |
| 3 |
450 MPa [65 ksi] |
380 MPa [55 ksi] | 18 |
| 4 |
550 MPa [80 ksi] |
483 MPa [70 ksi] | 15 |
| * 2% offset ** 51 mm [2 in] gauge length |
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