The influence of hydrogen on the sub-structure of the martensite and ferrite dual-phase steel

From this study, it is clear that the dislocation content increased and then resulted in the formation of subcells in the ferrite, at the ferrite-martensite interface, also the grain boundaries in ferrite widened, and cracks initiated along the interface and lath boundaries of the dual-phase steel if the charging current exceeded a critical value. These sub-structure changes in charged hydrogen dual-phase steel are similar to those caused by a small amount of plastic deformation. These structural changes may be a reason that dual-phase steels are susceptible to hydrogen embrittlement.