Pulse Electroplating of Silver-Tin Alloys and the Formation of Ag[sub 3]Sn

Silver‐tin alloys were electrodeposited at 50° by pulse plating from a bath containing ; ; ; and . The major variables studied were pulse cycle and current density. In the current density range of 1.5–3 A/dm2 with pulse on‐times of 5–100 msec and off‐times of 50–200 msec, the major constituent in the deposit was the intermetallic compound Ag3Sn. Several experimental conditions were determined in which the elemental tin and silver contents were small. The Ag3Sn coatings showed excellent integrity at thicknesses up to cm and were highly ductile. The tarnish resistance of the coatings was superior to that of pure silver.