Properties and microstructure of VC/Cr_3C_2-doped WC/Co cemented carbides  

作　　者：LEI Yiwen SUN Jing DU Xiwen ZHAI Qi HU Shengliang 

机构地区：[1]School of Mechanical and Electronic Engineering, Tianjin Polytechnic University, Tianjin 300160, China [2]School of Material Science and Engineering, Tianjin University, Tianjin 300072, China

出　　处：《Rare Metals》2007年第6期584-590,共7页稀有金属（英文版）

基　　金：the National Natural Science Foundation of China (No. 50372043).

摘　　要：This paper deals with the effects of codoped VC/Cr3C2 and sintering temperature on the magnetic and mechanical properties of ultra-fine grained WC-12%Co alloys. Results show that the synergistic action of doped VC/Cr3C2 in optimal proportion enhances both the hardness and transverse rupture strength （TRS） of the alloys, with more homogeneous microstructtLre. When the alloy is sintered at 1430℃ and with 0.5% Cr3C2/0.2% VC, the TRS reaches 3786 MPa, the hardness is 91.7 HRA and the grain size smaller than 0.6 μm. The numerical analyses on grain growth during the sintering process show that both VC precipitating on the WC grain boundary and Cr3C2 dissolving in the Co phase decrease the solid/liquid interfacial energy γ, the process of dissolution and reprecipitation is greatly retarded and the coarsening of WC grains is inhibited.This paper deals with the effects of codoped VC/Cr3C2 and sintering temperature on the magnetic and mechanical properties of ultra-fine grained WC-12%Co alloys. Results show that the synergistic action of doped VC/Cr3C2 in optimal proportion enhances both the hardness and transverse rupture strength （TRS） of the alloys, with more homogeneous microstructtLre. When the alloy is sintered at 1430℃ and with 0.5% Cr3C2/0.2% VC, the TRS reaches 3786 MPa, the hardness is 91.7 HRA and the grain size smaller than 0.6 μm. The numerical analyses on grain growth during the sintering process show that both VC precipitating on the WC grain boundary and Cr3C2 dissolving in the Co phase decrease the solid/liquid interfacial energy γ, the process of dissolution and reprecipitation is greatly retarded and the coarsening of WC grains is inhibited.

关 键 词：grain growth inhibitor ultra-fine grain cemented carbides MICROSTRUCTURE transverse rupture strength （TRS） 

分 类 号：TG13[一般工业技术—材料科学与工程]