论文部分内容阅读
采用真空熔烧的方法在45钢表面制得Ni-WC-CeO2复合涂层试样,利用光学显微镜、扫描电镜和能谱仪分析了CeO2添加量对涂层纵截面的微观组织形貌的影响,分析了WC的形貌和分布及熔烧带处的元素扩散情况。结果表明:CeO2的加入改善了涂层的组织,使其更加细小、均匀,消除了针状相;在CeO2添加量为0.75%时涂层和基体之间的互熔结合最好,涂层中的气孔、裂纹等缺陷最少;CeO2对合金元素原子的扩散有明显的促进作用,结合处主要以Fe、Ni扩散为主;CeO2改变了硬质相WC在涂层中的形貌和分布形式,使其变得细小、均匀、分散,促进了涂层中Ni基合金和WC之间的扩散,使WC在涂层中主要以4种形貌存在:条状、白色块状、灰色块状和灰色球状。
The sample of Ni-WC-CeO2 composite coating was prepared on the surface of 45 steel by vacuum melting method. The influence of the amount of CeO2 on the microstructure of the longitudinal section of the coating was analyzed by optical microscope, scanning electron microscope and energy dispersive spectrometer The morphology and distribution of WC and the elemental diffusion at the melting zone were analyzed. The results show that the addition of CeO2 improves the microstructure of the coating, making it more fine and uniform and eliminating the acicular phase. When the addition of CeO2 is 0.75%, the interfacial adhesion between the coating and the matrix is the best. And the defects such as cracks and pores are the least. The CeO2 promotes the diffusion of alloying elements atoms mainly with Fe and Ni diffusion. CeO2 changes the morphology and distribution of hard phase WC in the coating, Make it become small, uniform, dispersed, and promote the diffusion between the Ni-based alloy and the WC in the coating, so that the WC mainly exists in the coating in four morphologies: strip, white lump, gray lump and Gray globose.