AZ91D镁合金表面激光熔覆钴基合金涂层及性能分析  

Laser Cladding Co-Based Alloy Layer on AZ91D Magnesium Alloy and Properties

作　　者：颜瑞峰 郭亮 张庆茂 周永恒 张健 

机构地区：[1]广东省微纳光子功能材料与器件重点实验室,广东广州510006

出　　处：《应用激光》2012年第3期175-179,共5页Applied Laser

基　　金：中央财政支持地方高校专项资金资助项目(项目编号:510-C10293);广东省教育厅产学研结合重点项目(项目编号:2010A090200048);广东省教育厅学科建设专项资助项目(项目编号:CXZD1139);华南理工大学国家金属材料净成型工程技术研究中心开放基金资助项目(项目编号:2011006)

摘　　要：为改善AZ91D镁合金的表面性能,采用预置粉末脉冲激光熔覆法在镁合金表面制备钴基合金涂层,用扫描电镜(SEM)和能谱仪(EDS)分析熔覆层与基体结合界面特征、熔覆层成分。并结合Co-Cr相图、Co-W-C相图分析了熔覆层的组织形成过程,对基体及熔覆层显微硬度和耐蚀性进行测试。结果表明:合金层与基体冶金结合,熔覆层无明显缺陷;熔覆层硬度约为560HV达到基体的9倍;钴基合金层的耐蚀性能较高,自腐蚀电位比AZ91D镁合金基体提高1.18V,腐蚀电流降低约5个数量级。To improve the surface properties of magnesium alloy AZ91D, The purpose is to fabricate defect-free cladding layer on the surface of magnesium alloy AZ91D with pre-placed using YAG laser. The interface features and composition of cladding layer were studied through SEM and EDS. The forming process of cladding layer texture were studier through Co-Cr, Co-W-C phase diagram. The microhardness and corrosion resistance of substrate and cladding layer were texted. The results show that Co-based alloy cladding layer and the substrate achieve a good metallurgical bonding without obvious defects. The microhardness of Co-based alloy cladding layer is about 560 HV, more than 9 times to the substrate. Compared with AZ91D magnesium alloy, the corrosion potential of Co-based alloy layer is shifted by 1.18 V and the corrosion current is reduced to 5 order of magnitude.

关 键 词：激光技术 激光熔覆 AZ91D镁合金 钴基合金涂层 显微硬度 腐蚀性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]