Effects of Mo on the microstructure and properties of WC-(8Co, 2Ni) cemented carbide
GUO Juhua1, LI Bin1, HE Rengui2, WANG Jianying1, LOU Jia3, LIU Yanjun4, LI Yongxia4, YANG Hailin1
1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China; 2. School of Chemistry and Chemical Engineering, Gannan Normal University, Ganzhou 341000, China; 3. College of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China; 4. Hunan Boyun Dongfang Powder Metallurgy Co., Ltd., Changsha 410083, China
Abstract：In this work, the WC-(8Co,2Ni)-xMo (x=0, 0.5, 1.0, 1.5, mass fraction,%) composite powders were successfully prepared by chemical coating method, and then the WC-(8Co,2Ni)-xMo cemented carbides were fabricated by vacuum sintering method. The microstructure and phase composition of precursors and composite powders were studied. The effects of Mo on the microstructure, mechanical properties and corrosion resistance of WC-(8Co,2Ni) cemented carbide were investigated. The results show that the Mo in the WC-(8Co,2Ni)-xMo composite powders is uniformly distributed on the surface of the WC particles. The WC-(8Co,2Ni)-xMo cemented carbides are density, and have no obvious pores, WC and binder distribute uniformly. As the mass fraction of Mo increases from 0 to 1.5%, the average grain size of WC decreases from 1.6 μm to 1.1 μm. The hardness (HRA) of the alloy increases from (87.3±0.1) to (88.3±0.2), and the bending strength decreases from (2 890±27) MPa to (2 560±29) MPa. The low conductivity Mo-containing passivation film is formed during the corrosion process, so the corrosion resistance of the alloys is significantly improved.
郭巨华, 李彬, 何人桂, 汪建英, 娄嘉, 刘艳军, 李詠侠, 杨海林. Mo对WC-(8Co, 2Ni)硬质合金组织与性能的影响[J]. 粉末冶金材料科学与工程, 2022, 27(5): 488-497.
GUO Juhua, LI Bin, HE Rengui, WANG Jianying, LOU Jia, LIU Yanjun, LI Yongxia, YANG Hailin. Effects of Mo on the microstructure and properties of WC-(8Co, 2Ni) cemented carbide. Materials Science and Engineering of Powder Metallurgy, 2022, 27(5): 488-497.
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2022, Vol. 27 
