On hot deformation behavior and workability characteristic of 42CrMo4 steel based on microstructure and processing map  

作　　者：Min Qi Hong-yan Wu Ying Dong Lin-xiu Du 

机构地区：[1]State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,Liaoning,China

出　　处：《Journal of Iron and Steel Research International》2023年第3期537-547,共11页

基　　金：This study was funded by the National High-tech R&D Program(863 Program)(2015AA03A501);the Fundamental Research Funds for the Central Universities(N2107013).

摘　　要：In order to determine the safe region of 42CrMo4 steel during hot working and obtain excellent workability,the hot deformation behavior at the temperatures of 850-1150℃and the strain rates of 0.01-10 s^(-1)was investigated through single-pass compression test of thermo-simulation.Through observing and analyzing the true stress-strain curves,the conclusion may be drawn that the flow stress value increases with the decrease in deformation temperature and the increase in strain rate.Raising temperature and reducing strain rate are conductive to dynamic recrystallization(DRX)nucleating and growing,but adiabatic heating caused by higher strain rate can also promote it.Since the Zener-Hollomon(Z)value and dynamic recrystallized grain size(D_(DRX))have completely opposite trends with deformation condition parameters,the expression of Z value and DDRX can be determined as:D_(DRx)=15,567.645Z^(-02174).The processing map and instability map constructed at a strain of 0.9 show that the suitable window for hot working with a true strain of 0.9 is in the temperature range of 970-1150℃and strain rate range of 0.01-0.25 s^(-1),as well as at the temperature of 1150℃ and strain rate range of 0.25-10 s^(-1).The instability phenomenon appears in the process interval of 850-1096℃ and 0.22-10 s^(-1).

关 键 词：Hot deformation behavior Dynamic recrystallization Microstructure evolution Constitutive relationship Processing map 

分 类 号：TG142[一般工业技术—材料科学与工程]