镀金射频连接器焊点力学性能研究

Study on Mechanical Properties of Solder Joints for Gold Plated RF Connectors

在通信和雷达等电子装备中使用了大量的镀金射频连接器,该类连接器的装配不仅要保证其高装配精度和焊点可靠性,还要保证产品电参数和特性不发生变化,给射频连接器的装配带来了较大挑战。针对镀金射频连接器焊接中存在的问题开展工艺试验,包括印制板镀层工艺匹配性、焊点外观形貌和焊点力学性能等。试验结果显示,镀金层及镀金预处理工艺对焊点形貌和力学性能均有重要影响。当焊点中金含量较多时,焊点表面粗糙,润湿角大,焊点形态及焊点强度均无法满足要求,断裂位置发生在焊点中。采用薄金印制板及洗金工艺后,焊点中金含量减少,焊点强度明显增加。

Gold plated RF connectors are widely used in communication and radar electronic equipments. Assembly of the connectors faces great challenges because of high accuracy, solder reliability and high consistency of RF parameters. According to the problems in soldering, carried out experiments on process matching of PCB finishes, solder joint appearance and mechanical properties of solder joints. The results indicate that PCB finish types and tinning process has great influences on solder joint appearance and mechanical properties. When much gold exists in solders, the appearance and joint strength are unable to meet requirements due to rough and large wetting angle solders. While ENIG finish on PCB and lead tinning before soldering were used, gold content in solders decreased and strength of solder joints increased obviously.