Investigation on Hydrogen Embrittlement Mechanism of Metastable Austenitic Stainless Steel Using Micro-Mechanical Testing

采用显微拉伸试验结合金相分析，研究了马氏体对氢脆机制的影响。在氢存在下变形的底层组织强烈影响α马氏体的形成，导致过早的塑性失稳。在奥氏体相和马氏体相样品中，氢塑性变形获得的组织与无氢塑性变形组织相比，表现出较低的屈服应力和较差的应变硬化能力。这些结果表明，氢变形引起的缺陷对亚稳奥氏体钢的氢降解有很大的影响。

Micro-tension testing combined with metallographic characterization was used to investigate the effect of martensite on the hydrogen embrittlement mechanism. The underlying microstructure deformed in the presence of hydrogen strongly influences the formation of α’ martensite, leading to premature plastic instability. In both the austenite-phase specimen and the martensite-phase specimen, the microstructure obtained by plastic deformation with hydrogen exhibited low yield stress and poor ability of strain hardening when compared to the counterpart formed in the absence of hydrogen. These findings suggest that defects induced by deformation with hydrogen have a big impact on hydrogen degradation of metastable austenitic steel.