| 摘要 |
PURPOSE:To provide a solder alloy having an excellent fatigue resistance characteristic by alloying Sn, Bi and Ag at a specific ratio with Pb. CONSTITUTION:The alloy consisting of 20-47wt% Sn, 2-12wt% Bi, 0.015-1.5wt% Ag and the balance Pb is used as the solder alloy to be used in the stage of plating Ag on the surface of the circuit board in electronic parts such is various electronic circuit boards to form a conductive pattern thereon and soldering the terminals of lead wires thereto. The solder alloy which obviates the diffusion melting of the Ag plating on the surface of the circuit board into the solder alloy, i.e., the silver consumption phenomenon permits soldering at a low temp. and is free from the deterioration in the fatigue characteristic of the soldering part owing to repetitive stress is obtd. |
