Microstructures and properties of WC-20Co-1Y2O3 cemented carbide by hot-press and liquid phase sintering①
来源期刊：中南大学学报(英文版)2004年第2期
论文作者：张立 陈述 W. D. Schubert 黄伯云
文章页码：119 - 123
Key words：cemented carbide; rare earth; plate-like WC grain; bi-model structure
Abstract: Ultrafine tungsten carbide and fine cobalt as well as nano yttrium oxide powders were used as the raw materi-als. The effects of hot-press below the eutectic temperature and conventional liquid phase sintering on the structures and properties of WC-20Co-1Y2O3 cemented carbide were studied. It is shown that hot-pressed alloy has the character of isotropic properties and microstructure with homogeneous and ultrafine WC grains. However, the ultrafine and fully-den-sified structure is developed at the cost of the presence of large amount of cobalt-lake (unevenly distributed binder phase),and thus lower strength. Yttrium oxide in the alloy cannot play the role of grain growth inhibitor fully when cementedcarbide with high content of cobalt and ultrafine raw materials is sintered at high liquid phase sintering temperature. Pecu-liar platelet-enhanced bi-model structure is formed in WC-20Co-1Y2O3 cemented carbide by conventional liquid phase sin-tering, which points out that yttrium oxide in the alloy facilitates the formation of plate-like WC grain.
