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.