抄録
When we estimate the fatigue life of lead-free solder joints under cyclic temperature load, we have to get equivalent inelastic strain range accurately. In this study, in order to show the example of using our previously proposed constitutive model, which can describe stress strain curves, stress strain hysteresis loops and stress relaxation curves, with these temperature dependencies and these rate dependencies, we conducted FE analysis of the chip component under thermal cycle using the constitutive model. We also conducted fatigue tests of Sn3.5Ag0.5Cu0.07Ni0.01Ge lead-free solder using micro test pieces and estimated the fatigue life.
