AZ91D镁合金表面激光熔覆Ti_(74)Ni_(20)Si_4B_2涂层  

Laser Cladding Coating of Ti_(74)Ni_(20)Si_4B_2on AZ91D Magnesium Alloy Surface

作　　者：姚军[1] 崔反东 李仕臣 

机构地区：[1]内蒙古工业大学材料科学与工程学院,内蒙古呼和浩特010051

出　　处：《热加工工艺》2014年第18期127-129,133,共4页Hot Working Technology

基　　金：内蒙古自然科学基金资助项目(2009MS0805);内蒙古工业大学重点基金资助项目(ZD20080809)

摘　　要：为改善AZ91D镁合金的表面性能,采用6 kW连续CO2激光器在AZ91D镁合金表面熔覆Ti74Ni20Si4B2涂层。用光学显微镜和带能谱分析的扫描电镜观察熔覆层组织和结合区域的形貌以及元素分布,测试合金层的显微硬度、耐磨性和耐蚀性。结果表明,合金层与基体结合良好,并且元素分布没有明显界限。由XRD分析发现,生成TiBx、B4Si等化合物;通过对熔覆层和基体性能测试,发现平均显微硬度提高至625 HV0.05,耐磨性提高了1倍,极化曲线动态极化腐蚀电位提高了0.194 V,腐蚀电流密度降低了0.093 A·cm-2,在3.5%的NaCl溶液中耐腐蚀性能提高了约96%。In order to improve the surface properties of AZ91 D magnesium alloy, Ti74Ni20Si4B2 coating was deposited on the surface of AZ91 D magnesium alloy with 6 kW continuous CO2 laser. The coating microstructure, feature and distribution of elements in binding region were studied with OM and EDS analysis. The hardness, wear resistance and corrosion resistance of alloy layer have also been tested. Results show that alloy layer and matrix are well combined, There is no obvious boundary of element distribution. It is found that there are TiBx, B4 Si compounds with XRD analysis, the average microhardness value increases 625 HV0.05, wear resistance doubles, dynamic corrosion potential of polarization curve increases 0.194 V, density of corrosion current decreases 0.093 A/（cm2）. Corrosion resistance increases about 96% in 3.5%NaCl solution by testing the performance of the cladding layer and the substrate.

关 键 词：激光熔覆 Ti74Ni20Si4B2 耐磨 耐腐蚀 

分 类 号：TG174.44[金属学及工艺—金属表面处理]