镁合金表面电弧喷铝层的微观结构及界面分析  

Microstructure and interface analysis of aluminum coating sprayed by electro-arc spraying on AZ91D magnesium alloy

作　　者：马凯[1,2] 孙大千[1] 宣兆志[1] 陆佳[1] 

机构地区：[1]吉林大学材料学院,长春130022 [2]长春工程学院机电学院,长春130012

出　　处：《焊接学报》2008年第12期89-92,共4页Transactions of The China Welding Institution

基　　金：吉林省科技发展基金项目(20070309)

摘　　要：为获得性能优良的镁合金表面复合涂层,用自动送进的双铝丝做两个电极产生电弧,用压缩空气把熔化的铝熔滴喷到AZ91D镁合金表面,形成镁铝复合涂层。通过选用不同电压和气压进行喷涂试验,分析其对涂层组织性能的影响规律,找出最佳工艺参数。利用现代分析手段研究涂层的微观结构及界面特点,并通过测定涂层电极电位和盐雾试验分析涂层的耐腐蚀性能。结果表明,一定的电压和气压条件可使涂层致密,界面有新生组织,涂层中产生了小于50nm的纳米级晶团束和微米级层片状双重结构,涂层耐腐蚀性能明显优于镁合金基体。In order to obtain the excellent composite coating on magnesium alloy, double aluminum wires as two electrodes were automatically fed to create electric arc, the melting aluminum drops were sprayed on the AZ91D magnesium alloy surface by compressed air, and then the Mg-Al composite coating was formed. The optimum processing parameters were found by selecting different voltages and air pressure to carry on the spray experiments and analyzing the influence of the parameters on the coating structure performance. The characteristics of the coating microstructure and interface were researched by using the modern analysis methods, and the coating corrosion resistance was analyzed by test the coating electrode potential and the salt-spray experiment. The results indicate that certain voltage and air pressure can cause the coating to be compact. There is the newborn microstructure in the interface. The dual-structures of nano-scale crystal beam and micron-scale lamellar under 50 nm appear in the coating. The corrosion resistance of the coating surpasses that of the magnesium alloy matrix obviously.

关 键 词：镁合金 电弧喷铝 纳米晶 耐腐蚀性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]