镁合金AZ91HP强流脉冲电子束表面处理及抗蚀性能研究

研究了强流脉冲电子束表面处理对镁合金AZ91HP腐蚀性能的影响。通过动电位极化曲线测定，处理样品在5％NaCl溶液中的抗蚀性能有显著改善。72h盐浸失重法测试中，处理样品的腐蚀速度最大可以降低一个数量级。扫描电镜(SEM)及电子探针(EPMA)分析发现，强流脉冲电子束轰击处理在AZ91HP样品表层引发快速熔凝过程，进而导致镁、铝元素的含量及分布形式发生变化。样品表面重熔层中Al元素的过饱和固溶及成分均匀化是改善其腐蚀性能的主要原因。

Improvement in Corrosion Resistance of Magnesium Alloy AZ91HP by Surface Treatment of HCPEB

The influence of high current pulsed electron beam (HCPEB) treatment on the corrosion resistance of magnesium alloys AZ91HP was investigated in this paper. According to potentiodynamic polarization curves measurement, the treated samples exhibit an improved corrosion resistance in 5wt% NaCl solution compared with the initial samples. In the weight-loss experiment, the average corrosion rate of treated samples decreases by order of magnitude. By using SEM and EPMA analysis, rapid melting and solidification induced by the bombardment of HCPEB on the surface layer is observed, which leads to the re-distribution of alloy elements in the melted layer. Finally, the supersaturated solid solution of aluminum and the homogenization of element occurred in the surface layer are considered as the two main reasons which contribute to the improved corrosion resistance of AZ9HP alloy.