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 BH180
Coating type   GI/GA/ZM
Yield strength ReL N/mm2 180 - 240
Min. BH2 N/mm2 35
Tensile strength Rm N/mm2 290 - 360
Elongation % 34
Min. r-value r90   1.5
Min. n-value n90   0.16
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 BH180-GI/GA/ZM
C Max. 0.1
Mn Max. 0.7
P Max. 0.06
S Max. 0.025
Si Max. 0.5
Altot Max. 0.1
Ti Max. 0.12
Nb Max. 0.09
All values in weight%.