针对滤波器封装盒体气密性检查不合格的问题,运用扫描电镜以及电子探针能谱仪分别对气密性检查合格和不合格的盒体进行了微观结构和成分的分析比较,找出了盒体气体泄漏失效的原因。结果表明:由于气密性检查不合格的盒体材料硅含量偏高,且多以片状、颗粒状形式析出于铝合金表面,因而在此处产生了应力集中,导致了细微裂纹的产生;同时过高的硅含量还破坏了液相金属的焊接熔合性能,降低了熔合区域金属的致密度,使其容易产生焊接缺陷;上述两种原因共同作用最终导致盒体的气密性不合格。最后根据分析结论提出了改进措施。

Aimed at the problem of gas leakage of the package box used for filter, SEM and EDS were used to compare and analyze the different microstructure and element composition between the qualified and failure package box samples, and the failure causes were discussed. The results showed that the high concentration silicon was precipitated on the surface of aluminum alloy package box mostly in the flake and granular forms. That resulted in stress concentration, reduced the fusion performance of liquid metal welding and metal density in fusing zone, and eventually led to microcracks and welding defects. The improvement measures were proposed based on the results at last.