对电子产品Al盒体一种腐蚀现象的分析与措施

Analysis and Solution for Corrosion Phenomenon on Al Case

对2A12型Al盒体材料湿热试验后出现的一种腐蚀现象进行了观察和分析。采用X射线光电子能谱分析(XPS)的方法,对发生腐蚀的材料进行了成分分析,并进行了多种不同型号Al材料的比较试验。通过实验和分析,基本确认了腐蚀的产生是由电化学反应引起的,并指出了此腐蚀现象是由三防漆脱落造成Al表面和湿热环境直接接触引起的。增加Al盒体材料上的三防漆喷涂次数和增加涂层厚度的试验表明,加厚涂层能够使盒体承受更加严酷的湿热条件,是解决该腐蚀现象的途径之一。同时提出了防止三防漆划伤的改进措施,并对今后盒体材料的选取提出了建议。

A corrosion phenomenon in 2Al2 type Al case appeared after humidity test was observed and analyzed. The composition of the corroded material was analyzed by X-ray photoelectron spectroscopy （XPS）, and comparative test was implemented for various A1 materials. It is demonstrated that the corrosion phenomenon is caused by electrochemistry reaction, and the fundamental reason is conformal coating lift-off, which resulted in the direct contact of A1 surface with humidity environment. Increasing spray times and coating thickness on A1 case can improve resistance to harsh humidity, and it is proved to be the effective ways to solve the problem. Suggestions on the improvement of conformal coating scratch and case material choice were given.