2012 Volume 52 Issue 9 Pages 1670-1677
The effect of H on the mechanical properties of a high Mn twinning-induced plasticity steel was evaluated by comparing the properties of H-free and H-charged tensile specimens deformed at different temperatures prior to H-charging. The H-charging resulted in a reduction of the total elongation. The fracture surface of the tested samples revealed an inhomogeneous fracture appearance with an intergranular fracture in the range of 10 μm to 20 μm below the sample surface. The observations strongly suggest that it is this intergranular fracture in the surface layer which is the cause of the reduction of elongation in H-charged TWIP steel.