The effect of 104 mass ppm of hydrogen on the evolved microstructures associated with accelerated fatigue failure in type 304 austenitic stainless steel is reported. The fracture surface morphology changed from ductile striations to mixed mode that appeared “quasi-cleavage-like” and “flat.” Detailed microstructural characterization determined that these fractures were along the austenite–martensite interfaces. The morphology and orientation of the strain-induced martensite were impacted by the presence of hydrogen. Hydrogen constrained the formation of α′-martensite into linear, planar bands in the grains nearest the fracture surface, and ε-martensite was formed between the α′-martensite bands. The dislocation structure generated by the cyclic loading and the restriction of the martensitic transformation to specific forms by hydrogen is explained through the hydrogen-enhanced localized plasticity mechanism.

据报道，在304型奥氏体不锈钢中，氢104质量ppm的氢对与加速疲劳破坏相关的析出组织产生了影响。断裂表面形态从韧性条纹变为混合模式，呈现“准劈裂状”和“扁平状”。详细的微观结构表征确定这些裂缝沿奥氏体-马氏体界面。氢的存在影响了应变诱发马氏体的形貌和取向。氢将α'-马氏体的形成限制为最接近断裂面的晶粒中的线性平面带，在α之间形成了ε-马氏体马氏体乐队。通过氢增强的局部可塑性机制解释了循环载荷产生的位错结构以及氢将马氏体转变限制为特定形式的过程。