Effect of Bainite and Partial Martensite Transformation on Martensite Transformation Start Temperature
There are many high strength steels consist of multi-structure.Especially lath-shaped upper bainite and martensite are important structures in ultra high strength steels.So it is important to understand their transformation behavior with their interaction.In this study,we compare martensite transformation restart temperature (Mr) after quenching below martensite transformation start temperature (Ms),followed by austempering.This heat pattern is similar to Q&P process.But,in Fe-0.2C-8Ni alloy used,solute carbon content in austenite does not change with bainite transformation and tempering martensite at 673K.Without austempering,Mr on residual austenite after partially martensite transformation is equal to quench temperature.With austempering,although bainite transformation proceeds,Mr does not change from that without austempering.It seems that residual austenite made by quenching and austempering process memories the supercooling state of first quenching.
martensite bainite phase transformation Q-P process
KAWATA Hiroyuki HAYASHI Kunio YOSHINAGA Naoki TAKAHASHI Manabu
Steel Research Laboratories, Nippon Steel & Sumitomo Metal Corp., 20-1 Shintomi,Futtsu, Chiba, 293-8511 Japan
国际会议
成都
英文
402-405
2016-11-16（万方平台首次上网日期，不代表论文的发表时间）