Properties
Properties
Mechanical properties
Metallic coated high-strength steel grades have the following mechanical properties (skin-passed) - these are measured transverse to the rolling direction. Property range is indicated according to EN 10346, but properties meet equivalent VDA 239-100 specifications also.
Bake-hardening steels
Grade | CR BH300 | |
---|---|---|
Coating type | GI/GA/ZM | |
Yield strength ReL | N/mm2 | 300 - 360 |
Min. BH2 | N/mm2 | 35 |
Tensile strength Rm | N/mm2 | 400 - 480 |
Elongation | % | 26 |
Min. r-value r90 | - | |
Min. n-value n90 | - |
Lower yield strength or 0.2% proof stress applies.
BH2 refers to the increase of 0.2% proof stress after heating (bake hardening). Not applicable for hot rolled substrate.
Elongation after fracture A uses test piece length L0 = 80 mm.
For galvannealed grades (GA) the minimum elongation before fracture is lowered by 2%.
For galvannealed grades (ZF) the minimum r90-value is lowered by 0.2.
Chemical composition
Tata Steel supplies the following cast analysis with maximum values unless otherwise shown:
Bake-hardening steels
Grade | CR BH300-GI/GA/ZM | |
---|---|---|
C | Max. | 0.11 |
Mn | Max. | 0.8 |
P | Max. | 0.12 |
S | Max. | 0.025 |
Si | Max. | 0.5 |
Altot | Max. | 0.1 |
Ti | Max. | 0.12 |
Nb | Max. | 0.09 |