はんだ材料における迅速低サイクル疲労試験の適用可能性に関する研究

抄録

In this study, the method of estimating low cycle fatigue life of solders from the prompt fatigue test using a step-up method was investigated. Two kinds of solders of Sn-3Ag-0.5Cu (SAC) and Sn-58Bi (SB) were used. The fatigue testing using the step-up method was carried out with test temperature of 25°C, 60°C, and 125°C. The fatigue life equation of Manson-Coffin law was estimated from the reduction of area obtained from tensile test and the cyclic strain hardening coefficient obtained from fatigue test. The low cycle fatigue life obtained from a traditional fatigue testing was compared with the estimating fatigue life. As a result, this estimating result was corresponding to the low cycle fatigue life at each test temperature by the SAC solder. On the other hand, the low cycle fatigue life was estimated long with the SB solder at 25°C.