Bi对镁合金热浸镀铝镀层组织和厚度的影响  

Effect of Bi on Microstructure and Thickness of Hot-dip Aluminizing Coating on Magnesium Alloy

作　　者：薛寒松[1] 陈祖权[1] 向军军[1] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400044

出　　处：《热加工工艺》2013年第6期140-142,共3页Hot Working Technology

摘　　要：采用热浸镀方法在AZ31镁合金表面镀覆一层铝合金层。利用光学显微镜和配有能谱分析的扫描电镜等对镀层微观组织、元素分布等进行了研究;测定了试样在不同浸镀条件下的镀层厚度。结果表明:镀液添加Bi后,在浸镀温度不变情况下,镀层厚度增加速度加快,过渡层厚度变大,镀层中粗大的树枝晶增多,但是Bi在镀层中含量极少。通过对试验结果分析得出:Bi元素对Mg、Al液态互扩散具有显著的促进作用,使得镀层形成速度加快,但是也造成镀层组织粗大。The aluminum coating on AZ31 Mg alloy surface was prepared by hot dipping process. The microstructure of coating, distribution of element were studied by OM and SEM. The thickness of the coating was measured. The results show that after adding Bi into the hot-dipping solution, with the dipping temperature being constant, the increasing rate of the thickness of the coating becomes higher, the thickness of intermediate layer and the amount of coarse dendrite increases, but the amount of Bi in coating is extremely low. An analysis on the result of experiment shows that Bi can promote liquid mutual diffusion between Mg and A1, speed up the formation of coating, but also causes the formation of coarse structure.

关 键 词：镁合金 热浸镀 元素扩散 

分 类 号：TG178[金属学及工艺—金属表面处理]