碲元素对钴基合金显微组织及抗磨损性能的影响

Effect of Tellurium on the Microstructure and Wear Resistance of Cobalt-Based Alloy

为了解碲元素作为合金添加剂对钴基合金组织结构及性能的影响,配制碲添加量分别为0、0.5%、1.0%、1.5%、2.0%的含碲钴基合金粉末,采用粉末冶金烧结工艺制备钴基合金试样,利用OM、SEM、EDS、XRD分析钴基合金的金相组织和物相组成,并对含碲钴基合金的摩擦磨损性能进行了研究。结果发现:碲添加量在1.5%左右时,钴基合金的金相组织结构有显著改善,晶粒细小,晶界清晰,晶粒与基体结合紧密,碲元素起到细晶强化的作用;同时由于碲元素的添加在晶界处形成新相CoCrWTe,与基体上的富Co、Cr相镶嵌在基体上,对基体的强化支撑作用进一步增强,并且此时的含碲钴基合金耐磨损性能表现优异。

For exploring the effect of tellurium on the microstructure and wear resistance of cobalt-based alloy,the cobalt-based alloy powders with different tellurium additive amounts of 0,0.5%,1.0%,1.5%and 2.0%were configured,and subsequently the cobalt-based alloy samples were prepared by powder metallurgy sintering process.The metallographic and phase composition of cobalt-based alloy were analyzed by OM,SEM,EDS and XRD,and tribological properties of samples were studied.Results showed that when the amount of tellurium was about 1.5%,the microstructure of the obtained cobalt-based alloy was significantly improved:the grain size was small,and the grain boundary was clear,as well as the grain was tightly bound to the substrate,which resulted from the fine grain reinforcement function of tellurium element.Moreover,since the addition of tellurium element formed a new phase CoCrWTe at the grain boundary,the Co-rich and Cr-rich phases on the substrate were embedded in the substrate,which further strengthened the reinforcement of the substrate.Therefore,the as-prepared cobalt-based alloys containing tellurium performed excellent wear resistance.