添加碳化钨铁基合金等离子弧熔覆复合涂层的组织分析

Microstructure analysis on composite coating of Fe-based alloy added WC by plasma cladding

采用预置法等离子弧熔覆技术,在Q235钢基体表面熔覆了添加50%镍包WC(碳化钨)的Fe-Cr-B-Si合金粉末,制备了具有冶金结合的复合涂层.采用SEM,EDS,XRD等研究了涂层的组织,利用显微硬度计测试了涂层的显微硬度分布.结果表明,涂层与基体为冶金结合,其中部分WC分解,剩余WC主要分布在涂层的中、底部并与涂层结合良好,最后形成以γ-Fe为基,大颗粒WC,枝晶Fe3W3C,Fe6W6C,W2C等增强的复合涂层,涂层的显微硬度可达900～1100HV0.2.

By plasma cladding and appropriate processing parameters,a coating metallurgically bonded to substrate was prepared on substrate of Q235 steel using Fe-based alloy adding 50% WC.The microstructure of the clad layer was investigated by SEM,XRD,EDS,and the microhardness distribution of the coating was also tested by microhardness tester.The results show that the WC particles in the composites are partly melted into the coating,and others distribute at the central and the bottom of the coating,which bond with the coating well.The coating with good bonding with substrate mainly consists of γ-Fe,WC,Fe3W3C,Fe6W6C and W2C.The microhardness of the coating reaches 900～1 100 HV0.2.