Synthesis of Ag–SnO₂ Contact Material and Laser Bonding onto Cu Alloy Substate

Abstract

Ag–SnO₂ contact materials were synthesized by atmospheric oxidation of Sn+Ag mixed powders. For applying laser heating to fabricating electrical contact, the morphology of SnO₂ was altered by laser irradiation and the Ag–SnO₂ was welded onto Colson alloy–substrate. All the Sn added was selectively oxidized at 1050°C and a laser irradiation promoted a dispersion of separated spherical SnO₂ particles. Ag/Cu eutectic microstructures was found near the Ag–SnO₂/Colson alloy welding interface. Mg–Ni–Si oxide film formed on Colson alloy surface remained along the interface and may cause an increase in junction electrical resistance.