| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the fatigue strength of a soldered part by containing Sn, Sb, Ag, P, Pb, Cu, Bi, Ni, Ge, Te, Ga and In of the prescribed quantity in the solder. SOLUTION: The solder has the composition consisting of, by weight, 50-80% Sn, 0.05-10% Sb, 0.0001-5% Ag, 0.0001-0.5% P, and at least one kind of the element S to be selected among 0.01-1% Cu, 0.01-5% Bi, 0.01-5% Ni, 0.001-0.5% Ge, 0.001-1% Te, 0.001-1% Ga, and 0.001-1% In, and the balance substantially Pb. Sb increases the strength. If Sb is excessive, the flowability of the solder is reduced. Ag increases the strength and improves the softness. P increases the strength, suppresses the oxidizing reaction, and improves the stress resistance to withstand the thermal stress and vibration of a soldered part. If P is excessive, the flowability of the solder is reduced.</p> |
