Abstract The powders with main phase of η phase were synthesized via the carbonization of W, Co, C and TiC mixtures firstly, WC-TiC-Co composite powders with different carbon contents were then synthesized by the carbonization of the η phase powder. WC-TiC-Co cemented carbides were prepared by vacuum sintering. The effects of carbon contents on the phase consistent, grain size, morphology and mechanical performance were investigated. The results show that the carbon content is the key factor affecting the phase composition and grain size of the alloy. The η phase with irregular shape remains in carbon-poor alloys and forms a metallurgical bonding with WC phase. Co phase tends to distribute at the interface between WC and (Ti,W)C phases. WC grains in carbon-rich alloys show a more regular shape than that in carbon-poor alloys. The size of WC and (Ti,W)C phase increase and the W content in (Ti,W)C phase and binder phase also increases. The alloy with suitable carbon amount has the hardness (HRA) of 91.7, the transverse rupture strength of 1678 MPa and the fracture toughness of 10.2 MPa∙m1/2.
LUO Ren,XIONG Huiwen,CHEN Nan, et al. Effects of carbon content on the microstructure and performance of WC-TiC-Co cemented carbides[J]. Materials Science and Engineering of Powder Metallurgy, 2020, 25(5): 381-388.
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2020, Vol. 25 
