AZ91D镁合金表面激光熔覆Ni基+WC合金涂层  

Laser Surface Cladding of AZ91D Magnesium Alloy with Ni-Based and WC Powders

作　　者：黄伟容[1] 肖泽辉[1] 

机构地区：[1]湘潭大学机械工程学院,湖南湘潭411105

出　　处：《中国激光》2009年第12期3267-3271,共5页Chinese Journal of Lasers

基　　金：湖南省教育厅青年项目(05B005)资助课题

摘　　要：采用激光熔覆技术在镁合金表面制备了Ni基合金+WC复合陶瓷涂层,并对不同WC含量下的复合涂层进行了成分和性能分析。研究结果表明,激光熔覆涂层与基体之间获得了良好的冶金结合;涂层主要由AlNi3,Al3Ni2金属间化合物以及Ni(Cr2O4)和多种碳化物组成;质量分数为25%WC的加入减少了涂层中孔隙和裂纹的存在,与基体相比,涂层的硬度提高了约9.4倍,弹性模量提高了约2.06倍;耐蚀性也得到了明显提高。The laser surface cladding of AZ91D magnesium alloy with Ni-Cr-B-Si＋WC powders has been investigated. Laser surface cladding was conducted using a continuous wave CO2 laser. As a result,a good metallurgical bond interface was obtained between Mg alloy substrate and coating. The microstructure and phase analysis of the coating were carried out by scanning electron microscope （SEM） and X-ray diffraction （XRD）. The hardness and the corrosion properties of the coating were also measured. The experimental results show that the cladding layer is composed of AlNi3,Al3Ni2,Ni（Cr2O4） and different kinds of carbide. The cracks and porosity of coating are decreased with the join of 25% WC particles. The hardness of the cladding layer is significantly improved by 9.4 times higher than that of the AZ91D substrate,and the modulus is about twice higher than that of the substrate. The corrosion resistance of the laser modified samples is considerably improved as compared to the substrate.

关 键 词：激光技术 镁合金 涂层 激光熔覆 WC 

分 类 号：TG156.99[金属学及工艺—热处理] TN249[金属学及工艺—金属学]