The effect of rare earth metals(REM)on the characteristics of auto-tempering and decomposition of martensite for low-carbon and low-alloy steels(20SiMn2V and 20SiMn2VRE)was investigated using TEM,dilatometer and micro...The effect of rare earth metals(REM)on the characteristics of auto-tempering and decomposition of martensite for low-carbon and low-alloy steels(20SiMn2V and 20SiMn2VRE)was investigated using TEM,dilatometer and microhardness test.Results show that both ε.and θ carbides,during auto-tempering, may precipitate from the low-carbon martensite matrix at the same time in the 20SiMn2V steel,however,the precipitation of the ε-carbides can be inhibited by the REM contained in the 20SiMn2 VRE steel,resulting in change of the type of precipitated carbides and decrease of the extent of auto-tempering.The“in-situ”ob- servations show that the decomposition of martensite is also inhibited by the REM contained in the 20SiMn2 VRE steel during low temperature tempering.展开更多
文摘The effect of rare earth metals(REM)on the characteristics of auto-tempering and decomposition of martensite for low-carbon and low-alloy steels(20SiMn2V and 20SiMn2VRE)was investigated using TEM,dilatometer and microhardness test.Results show that both ε.and θ carbides,during auto-tempering, may precipitate from the low-carbon martensite matrix at the same time in the 20SiMn2V steel,however,the precipitation of the ε-carbides can be inhibited by the REM contained in the 20SiMn2 VRE steel,resulting in change of the type of precipitated carbides and decrease of the extent of auto-tempering.The“in-situ”ob- servations show that the decomposition of martensite is also inhibited by the REM contained in the 20SiMn2 VRE steel during low temperature tempering.