The influence of hydrogen flux on crack initiation in martensitic steels

Understanding hydrogen transport and trapping phenomena is a key feature to revisit the hydrogen embrittlement (HE) models proposed in the literature. Both aspects can be affected by stress-strain states at different microstructural scales. Elastic distortion and plastic strain are both aspects of the mechanical states associated with defects (vacancies, dislocations), metallurgical elements (grain boundaries, precipitates), internal stresses and applied stresses, which can modify the diffusion and solubility of hydrogen. In the present work we first explore the effects of a tensile stress applied on martensitic steel membrane on the hydrogen concentration and mobility. In a second part, we analyse the impact of mobile and trapped hydrogen on HE using local approach of fracture under hydrogen flux. (C) 2014 Published by Elsevier Ltd.