奥氏体不锈钢中应变诱导α′-马氏体作为氢扩散通道的研究

Research on strain-inducedα′-martensite as hydrogen diffusion channel in austenitic stainless steel

研究了304和316L奥氏体不锈钢(ASS)的组织演变和氢脆行为。用热脱附光谱仪测定了304和316L ASS的氢脱附速率和氢含量。结果表明,与固溶处理的304 ASS相比,冷轧样品中产生了应变诱导α′-马氏体,氢含量增加,氢脆敏感性增加;然而,316L ASS冷轧后产生极少量α′-马氏体,氢含量较少,氢脆敏感性很低。4个样品在充氢前的断裂均为韧性断裂,冷轧316L ASS在充氢后的断裂为准解理和解理断裂,而冷轧304 ASS在充氢后的断裂为晶间断裂。确定了应变诱导α′-马氏体在氢扩散和氢脆机制中的作用。

The microstructural evolution and hydrogen embrittlement(HE)behaviors of 304 and 316L austenitic stainless steel(ASS)were investigated.The hydrogen desorption rate and hydrogen content of 304 and 316L ASS were measured by thermal desorption spectrometer.The results show that compared with the solution-treated 304 ASS,the strain-inducedα′-martensite is produced in cold-rolled sample,the hydrogen content increases,and the HE sensitivity increases.However,littleα′-martensite is produced after cold rolling of 316L ASS,the hydrogen content is less,and the HE sensitivity is very low.The fractures of the four samples are all ductile fractures before hydrogen charging and that of the cold-rolled 316L ASS is quasi-cleavage and cleavage fracture after hydrogen charging,while the fracture of cold-rolled 304 ASS is intergranular fracture after hydrogen charging.The role of strain-inducedα′-martensite in hydrogen diffusion and HE mechanism is determined.