摘要
同时采用电阻测量方法和疲劳裂纹观测方法分析表面贴装结构焊点的热疲劳破坏过程.通过研究焊点在热疲劳过程中的电阻值变化和热疲劳裂纹的扩展过程,来比较传统锡铅钎料焊点和无铅钎料SAC305焊点的热疲劳破坏规律.并结合有限元分析,研究焊点在热疲劳过程中的电阻值变化与裂纹扩展之间的关系,从而获得一种工程上较为实用的焊点热疲劳失效的电阻值经验判据.结果表明,SAC305无铅钎料焊点相对于传统锡铅钎料焊点而言,具有较为优异的抗热疲劳性能.根据试验研究和有限元分析结果建立了焊点在热疲劳过程中发生失效的电阻值经验判据.
The failure process of soldered joint in SMT was investigated by electrical resistance measurement method and crack observation method.The characteristics of electrical resistance value variation of lead-tin and lead-free soldered(SAC305) joints during the thermal fatigue test were obtained.And at the same time the crack propagation in soldered joint was observed.According to these measurements,the failure rules of lead-tin and lead-free soldered joint were compared.The relationship between electrical resistance value variation and crack propagation of soldered joint during thermal fatigue test was studied by FEM,and an empirical criterion to estimate the failure of the soldered joint in the thermal fatigue test was obtained based on electrical resistance value variation.The experimental results show that the lead-free soldered joint has a higher resistibility in thermal fatigue than the traditional lead-tin soldered joint.The criterion based on electrical resistance value variation was founded from the experimental and simulation results.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2009年第11期65-68,72,共5页
Transactions of The China Welding Institution
基金
北京市属市管高等学校人才强教计划资助项目
现代焊接生产技术国家重点实验室开放课题研究基金资助项目(09010)
