Research on Nanocrystalline WC-8(Fe、Co、Ni)RE Cemented Carbide

Research on Nanocrystalline WC-8(Fe、Co、Ni)RE Cemented Carbide
　　The WC cemented carbide is widely used in various industrial fields such as cutting tools、molds, mine tools and anti-wear accessories due to the special wearability, high hardness, fine fracture toughness and compressive strength. However, in our country, the output of the WC cemented carbide is difficult to meet the demands because of the long-term shortage of Co resources. So, it is very urgent to seek substitutes for Co. In the paper, the Fe and Ni which characters and structures are similar to Co but much cheaper were tried to substitute for Co.The WC-8Co/RE Cube neodymium magnet cemented carbide had been researched before investigating WC-8(Fe/Co/ Ni)RE.
　　The techniques and theories of the WC-8Co/REcemented carbide experiments have certain guidance to the experiment of WC-8(Fe、Co、Ni). Comparing the results of two experiments, the deficiencies of WC-8(Fe、Co、Ni) were pointed out and reformed.In the paper, the WC-8(Fe、Co、Ni)RE alloy were prepared by the conventional powder metallurgy. The mechanical properties and the microstructure of WC-8(Fe、Co、Ni)RE cemented carbide were investigated mainly. With the comparison between the cemented carbide that iron and nickel replace for cobalt and the traditional cemented carbide, The experiments had shown results that the sintering temperature of WC-8(Fe、Co、Ni) cemented carbide is obviously higher than YG’s and the new kind of cemented carbide could been achieved the liquid phase sintering and could been obtained well density when as the sintering temperature is higher at 1430℃. When the proportion of Fe、Ni and Co is 65:20:15 and 20:20:60 respectively, the hardness of the cemented carbide achieves was about 90.7HRA and full density of the sintering sampaes could been obtained nearly. At the same time, the mechanical properties of the sintered samples were higher than the traditional YG8. The 1wt% additive of rare earth could not http://www.chinamagnets.biz/ Cube neodymium magnet only restrain the growth of WC crystal but also improve their mechanical properties. The hardness of WC-8Co cemented carbide have achieved 92.2HRA, which is much higher than WC-8(Fe、Co、Ni). The mechanical properties of WC-8(Fe、Co、Ni) cemented carbide could be improved through optimizing the technology, but in the same technology, it had lower properties than the one of the WC-8Co/RE, because of the high sintering temperature and the difference of the components.