材料期刊网

The effect of the gap size on the shear strength of a solder joint was investigated in both Sn/Cu and Sn/FeNi lap solder joints by varying the gap size from 20 mu m to 300 mu m. In the Sn/FeNi joints, the shear strength remained relatively constant, around 14 MPa, independent of the gap size. In contrast, the shear strength of the Sn/Cu joint decreased about 20% from 25 MPa to 20 MPa. The decrease was shown to result from Cu6Sn5 precipitation in the thicker Sn/Cu joint, which was absent in the thinner joints.