稀土在WC颗粒复合耐磨材料中的作用

为了提高ＷＣ硬质合金颗粒复合材料的耐磨性，向复合材料的金属基体中加入了不同数量的稀土。采用扫描电镜、Ｘ射线能谱仪、显微硬度计、台式冲击试验机以及销盘式磨损试验机等试验手段，对稀土加入量不同的几种ＷＣ硬质合金颗粒复合材料的金属基体进行了稀土分布及显微组织的分析，测定了基体组织的显微硬度及复合材料的韧性和耐磨性。研究结果表明，稀土富集于奥氏体与碳化物和奥氏体与共晶体两种界面处，少量固溶于奥氏体中。加入适量的稀土产生了明显的微合金化作用，使共晶组织显著细化，提高了金属基体的硬度和韧性以及复合材料的耐磨性。

Effect of rare earth in complex wear resistant material containing WC granules

Different amounts of rare earth were added into a WC Particlereinforced metal matrix composite material in order to increase its wear resistance. Scanning electron microscopy, energydispersive X ray analyzer, microhardness tester, impact tester and pin on dise wear machine were used. The distribution of rare earth and microstructures of metal matrixes of several composite materials containing WC granules and added different amount rare earth were analysed. The microhardness of the matrix microstructures as well as the toughness and wear resistance of the composite materials were measured. The results show that the rare earth is distributed mainly at the interfaces of austenite and carbide as well as austenite and eutectic, very a few solid solution in the austenite. An approriate addtion rare earth produces obvious microalloying effect, the eutectic microstructures have been markly refined, the hardness, toughness and wear resistance of the composite materials have been enhanced as well.