热处理对ZG06Cr13Ni4Mo不锈钢组织与性能的影响

研究了不同正火温度、回火保温时间和冷却方式对低碳马氏体不锈钢ZG06Cr13Ni4Mo组织与力学性能的影响。利用光学金相显微镜(OM)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射仪(XRD)对材料的微观组织和结构进行了研究。进行了室温拉伸和0℃冲击试验,并用SEM观察了断口形貌。结果表明,正火温度对ZG06Cr13Ni4Mo不锈钢组织与性能有显著影响。在γ+δ两相区正火时,会生成高温δ铁素体,并且δ在随后的热处理中不能被消除,即使很少的铁素体(1%),也会极大损害材料的韧性。采用较快冷却时,材料的韧性较高而强度较低;较长时间的回火保温,材料的强度较低,与较短时间保温下相比韧性没有明显差别。

Effects of heat treatment processes on microstructure and mechanical properties of ZG06Cr13Ni4Mo stainless steel

Effects of different normalizing temperatures,tempering temperatures and holding times,cooling rates on microstructure and mechanical properties of low carbon martensite stainless steel ZG06Cr13Ni4Mo was studied.Microstructure and phase composition of the steel were observed by OM,SEM,TEM and XRD.Room temperature tensile test and 0 ℃impact test were carried out,and fracture morphology of the steel was characterized by SEM.The results show that the normalizing temperature has a great influence on the low carbon martensite stainless steel.When the normalizing temperature reaches γ+δ dual phase region,δ ferrite is formed and it’s hard to be eliminated during the following heat treatment processes.Even very low content of δ ferrite(about 1%) will do harm to toughness of the steel.Under faster cooling rate,the steel can obtain higher toughness and lower strength.A longer time tempering induces lower strength,while the ductility has no significant difference compared to shorter time tempering.