高剛性ラップジョイント試験片によるはんだ接合部の疲労強度特性に及ぼす接合厚さの影響

抄録

In this paper, fatigue strength properties of Sn-3.0Ag-0.5Cu solder joints were evaluated by using a high-rigidity lap joint specimens, in which two copper adherends are joined with solder. That is, shear fatigue tests were conducted by using the specimens with the joint thickness of 0.1mm. In order to investigate the effect of joint thickness on fatigue strength properties, the obtained data were compared with the data under the condition of the joint thickness of joint thickness of 0.4mm obtained previously. In the tests, the fatigue crack initiation lifetime N_20%drop was defined as the number of cycles when the load amplitude was reduced by 20% from the initial cycle. The following results were obtained. First, there was hardly any difference in the N_20%drop due to the difference in the joint thickness. Second, it was clear that the lifetime from N_20%drop to the fracture becomes shorter as the thickness of the joint becomes thinner.