Evolution of carbides on surface of carburized MSONiL bearing steel  

作　　者：Jiang-long Lian Li-jing Zheng Fang-fang Wang Hu Zhang 

机构地区：[1]School of Materials Science and Engineering,Beihang University,Beijing 100191,China

出　　处：《Journal of Iron and Steel Research International》2018年第11期1198-1211,共14页

基　　金：National Natural Science Foundation of China under Grant NSFC 51471012.

摘　　要：The dissolution and precipitation behaviors of the carbides in carburized M50NiL steel were derived from different solution and tempering treatments.Totally four kinds of carbides of (V,Cr)-rich MC,(Mo,Fe)-rich M2C,Fe-rich M3C and (Fe,Cr)-rich M7C3 were obtained from the carburized M50NiL steel after different heat treatments.The key carbides of carbufized M50NiL steel were proved to be tough V-rich MC and Cr-rich M7C3.The highest hardness (634 HV)and the optimal surface structure with 1.0% volume fraction of uniformly distributed MC carbides were obtained after the carbufized M50NiL steel was solution-treated at 1150 ℃ and tempered at 500 ℃.The quantitative statistics show that 63%of the MC carbides were less than 200 nm under that heat treatment.The variety of carbides changed with solution and tempering conditions.When the solution temperature increased from 1050 to 1150 ℃,the undissolved carbides were proved to be Fe-rich M7C3,Mo-fich MC and (Mo,Fe)-fich M2C.Besides,the equivalent content of V-rich MC was found increased when the tempering temperature changed from 500 to 550 ℃.The combination of high-temperature solution and low-temperature tempering is recommendable heat treatment for the high hardness as well as the tiny and uniformly distributed carbides.

关 键 词：M50NiL STEEL CARBIDE CARBURIZATION HARDNESS HEAT treatment 

分 类 号：TF[冶金工程]