论文部分内容阅读
利用升温脱氢分析(TDS)实验研究了1000 MPa级0Cr16Ni5Mo马氏体不锈钢的氢陷阱行为.同时,采用慢应变速率拉伸实验(SSRT)研究了该钢缺口与光滑试样的氢脆敏感性,并利用SEM观察了试样的断口形貌.结果表明,位错和晶界为该钢的主要氢陷阱,充氢后缺口试样与光滑试样的伸长率均下降明显,但强度变化不大.随着氢含量的升高,断口形貌由韧窝型韧性断裂向穿晶、准解理断裂,甚至向沿晶断裂方式过渡.由于C含量较少,该钢的不可逆陷阱含量极少,大量的可扩散氢使得该钢具有较高的氢脆敏感性.最后利用与Eshelby等效夹杂理论有关的氢致应力模型,验证了应力集中与氢含量之间的变化关系.
The hydrogen trapping behavior of 1000 MPa grade 0Cr16Ni5Mo martensitic stainless steel was studied by means of temperature-rise dehydrogenation analysis (TDS). Meanwhile, the hydrogen embrittlement susceptibility of the steel notch and smooth specimen was studied by slow strain rate tensile test (SSRT) , And the fracture morphology of the samples was observed by SEM.The results show that the dislocations and grain boundaries are the major hydrogen traps of the steel and the elongation of both the notched samples and the smooth samples decreases obviously after the hydrogen charging, Is not large.With the increase of hydrogen content, the fracture morphology changes from dimple-type ductile fracture to transgranular, quasi-cleavage fracture, and even to the intergranular fracture mode.As the C content is less, the irreversible trap content of steel The large amount of diffusible hydrogen makes the steel highly susceptible to hydrogen embrittlement.Finally, the hydrogen stress induced by Eshelby’s equivalent inclusion theory is used to verify the relationship between stress concentration and hydrogen content.