Interfacial reactions of Sn–Zn–Ag–Cu alloy on soldered Al/Cu and Al/Al joints

Abstract

This work shows the effect on the soldering process of the addition of Ag and Cu to Sn-Zn alloys. Soldering of Al/Cu and Al/Al joints was performed for a time of 3 min, at a temperature of 250°C, with the use of flux. Aging was carried out at 170°C for Al/Cu and Al/Al joints for 1 and 10 days. During the aging process, intermetallic layers grew at the interface of the Al/Cu joint at the Cu substrate. Intermetallic layers were not observed during wetting of Al/Al joints. On the contrary, dissolution of the Al substrate and migration of Al-rich particles into the bulk of the solder were observed. The experiment was designed to demonstrate the effect of Ag and Cu addition on the dissolution of Al substrate during the soldering and aging processes. In the solder alloys, small precipitates of AgZn 3 and Cu 5 Zn 8 were observed.

Electrochemical corrosion behaviour of Sn–Sb solder alloys: the roles of alloy Sb content and type of intermetallic compound

“…However, due to recent legal restrictions for Pb-based solders, Pb tends to be banned from industrial parts due to its harmful effects on human health and to the increasing environmental concerns over its toxicity. In recent years, the legislation has become even more restrictive, which has significantly increased the research and development of lead-free solder alloys [1][2][3][4]. Not only good electrical and thermal performances are required of a solder alloy but also mechanical and electrochemical reliability [5,6].…”