STRENGTH OF TIN-BASED SOLDERED JOINTS

Single overlap joints of copper and brass soldered with tin and tin-based solders containing (wt %) 1% Cu, 3.5% Ag, 5% Sb, 57% Bi, and 2% Ag 36% Pb, have been tested in shear at 20 and 100-degrees-C, and with strain rates of 0.05 and 50 mm min-1. Six specimens were tested under each condition, and the average value and coefficient of variation of the 0.2% yield stress, ultimate shear stress, elongation, and work to fracture, determined. Brass joints were generally slightly stronger than copper joints, and tended to show more scatter. Ranking in terms of strength depended on the test conditions. The solders containing silver generally gave the strongest joints. Strain-rate sensitivities were less than 0.1 , and activation energies for deformation were very low. Overall, there did not appear to be any regular pattern between the properties, solders, and test conditions.