温度对金锡合金焊料共晶形貌影响机制研究

Study on the Influence Mechanism of Temperature on AuSn20 Solder Eutectic Morphology

金锡焊料熔封作为典型的高可靠气密封装方式,广泛应用于航空航天、船舶舰艇、导弹雷达、装甲坦克等装备系统器件。鉴于金锡焊料环对成分和质量有严格的控制要求,在实际应用中会由于管壳、盖板母材及其镀层的参与造成对共晶点的偏离,得到更为复杂的焊接状态。为深入剖析封装机理、提高封装质量,对影响共晶界面形貌最为重要的温度因素展开研究。设定不同峰值温度,通过扫描焊接样品截面,观察界面化合物状态和分布,研究密封过程中工艺参数对封焊区微观形貌的影响,得到焊缝厚度、树枝晶化合物厚度、Ni元素扩散距离等界面状态随峰值温度变化的趋势,为进一步提高金锡焊料熔封可靠性提供理论参考。

As a typical high-reliability airtight packaging method,AuSn20 solder fusion sealing is widely used in aerospace,ships,missiles,radars,armored tanks and other equipment system devices.In view of the strict control requirements on composition and quality of AuSn solder ring,in practical application,the deviation from eutectic point will be caused by the participation of the shell,the base material of the cover plate and its coating,and a more complicated welding state will be obtained.In order to deeply analyze the packaging mechanism and improve the packaging quality,the most important temperature factor affecting the morphology of eutectic interface was studied.Setting different peak temperatures,observing the state and distribution of interface compounds by scanning the cross section of welding samples,and studying the influence of process parameters on the micro-morphology of the sealing area during the sealing process,the trends of interface states such as weld thickness,dendrite compound thickness and diffusion distance of Ni element changing with the peak temperature are obtained,which provided theoretical reference for further improving the sealing reliability of AuSn20 solder.