热处理对汽车发电机奥氏体钢微观组织及力学性能的影响

Effect of Heat Treatment on Microstructure and Mechanical Properties of Automobile Generator Austenitic Steel

以汽车发电机奥氏体钢为研究对象,分析了热处理对汽车发电机奥氏体钢微观组织及力学性能的影响。结果表明:奥氏体钢在拉伸试验过程中,晶粒比较粗大,且存在的晶界数较多;在冲击试验过程中,经过压缩变形后,随压缩速率不断增加,晶界数目不断增加,晶粒也逐渐趋于细小、均匀;奥氏体钢的屈服强度为250 MPa,抗拉强度为896 MPa,伸长率为19%,冲击韧度为175J/cm^2;随真应变增加,真应力不断增加,而加工硬化率呈现先减小后增大的趋势;随冲击次数、冲击变形量增加,表面维氏硬度也逐渐增加;随表面距离增加,表面维氏硬度却逐渐减小;随冲击次数增加,冲击变形量逐渐增加。

Austenitic steel of the automobile generator was regarded as the research object; the effects of heat treatment on microstructure and mechanical properties of automobile generator austenitic steel were analyzed. The analysis results show that in the process of tensile experiments, the grain of the austenitic steel is bulky and exists mostly on the number of grain boundary, in the process of impact test, after compression deformation, with the compression rate increasing, the number of grain boundary increases and grain also gradually tends to be small, uniform; austenitic steel yield strength is 250 MPa, the tensile strength is 896 MPa, the elongation is 19%, and the impact toughness value is 175 J/cm2; with the increase of true strain, true stress increases and strain hardening rate first increases then decreases; with the increase of impact frequency and impact deformation, surface vickers hardness gradually increase; with the increase of the surface distance, surface vickers hardness decreases; with the increase of impact times, impact deformation gradually increases.