Morphology and Formation Mechanism of Bainite of Chromium-Molybdenum Steel
Bainite is a kind of complex microstructure integrated in a systematic way essentially. The morphology and formation mechanism of bainite of 12CrMo, 20CrMo, 35CrMo and 9CrMo steels were studied by metallographic microscope and QUANTA-400 environmental scanning electron microscope after they were austenitized and then quenched at average temperature areas respectively. The results show that massive or lamellar carbide-free bainite is obtained after the average temperature isothermal phase transformation of the low chromium-molybdenum steels. The upper bainite of medium carbon chromium-molybdenum steel is carbide-free bainite, but there is carbide separated out in the lower bainite. Feathery upper bainite and bamboo leaf shaped lower bainite can be obtained when the high carbon steel is isothermal quenched in average temperature areas. The carbon content has a significant effect on the morphology of bainite. It is considered that with increase of carbon content, the carbon-rich austenite films are remained among the bainite ferrite laths. Free carbon bainite will be gotten when the ferrite laths can not mix together. Feathery upper bainite will be gained if carbide precipitates from carbon-rich austenite among the bainite ferrite laths. Bamboo leaf shaped lower bainite will be obtained if carbide precipitates from BF/γ phase interface so that bainite ferrites are divided into many fine subunits.
Bainite carbide nucleation integrating in a systematic way
JI Yun-ping LIU Zong-chang LI Wen-xue DUAN Bao-yu REN Hui-ping
School of Material and Metallurgy,Inner Mongolia University of Science and Technology,Baotou,China
国际会议
The Fourth Asian Conference on Heat Treatment and Surface Engineering(第四届亚洲热处理及表面工程大会)
北京
英文
93-98
2009-10-27（万方平台首次上网日期，不代表论文的发表时间）