Effects of vacuum degree and carbon content on microstructure and tensile properties of M2 high speed steel
LIU Ruiqing1, HE Hao2, LOU Jia3, LI Yimin1,2, LI Song1, LIU Chen2, QIN Jianchun2
1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China; 2. Materials Science and Engineering Research Center, Guangxi University of Science and technology, Liuzhou 545006, China; 3. School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China
Abstract：The M2 high speed steel was prepared by vacuum sintering process. The effects of vacuum and carbon content on microstructure and properties of M2 high speed steel were studied. The results show that the effective sintering temperature of M2 HSS under low vacuum (10-1 Pa) is 1 220-1 230 ℃, and its relative density is above 96%. The microstructure of M2 is composed of austenitic matrix, M6C and MC carbides after sintering. When vacuum degree increases to 10-3 Pa,the effective sintering temperature of M2 HSS decreases, and the carbides in the matrix are finer and more evenly distributed. The relative density of the sintered sample is 98%, and its tensile properties and elongation reached 989 MPa and 7.1%, respectively. With the increase of carbon content, there is no obvious change in sintering interval of M2 high-speed steel, but the densification can be easier to achieve at lower temperature. When the mass fraction of carbon is 1.0%, the relative density of the sample is 97%, its tensile strength and elongation are 954 MPa and 7%, respectively.
刘瑞卿, 何浩, 娄嘉, 李益民, 李松, 刘晨, 秦健春. 真空度及碳含量对M2高速钢组织和拉伸性能的影响[J]. 粉末冶金材料科学与工程, 2019, 24(6): 508-514.
LIU Ruiqing, HE Hao, LOU Jia, LI Yimin, LI Song, LIU Chen, QIN Jianchun. Effects of vacuum degree and carbon content on microstructure and tensile properties of M2 high speed steel. Materials Science and Engineering of Powder Metallurgy, 2019, 24(6): 508-514.
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2019, Vol. 24 
