Fabrication of trimetallic strips by explosive cladding and rolling

Abstract The fabrication of trimetallic composite contacts for electrical and electronic switches is reported. A thin layer of solder metal is explosively cladded onto a copper plate, the resulted bimetallic strip is rolled to a thickness of 2 mm and the cladded/rolled bimetallic is explosively cladded onto a 5 mm thick silver plate. Rolling is subsequenty used for forming the trimetallic composite to its final thickness. The effect of the cladding/rolling variables on the integrity, the soudness and micro- and macrostructural properties of the fabricated composite plates is evaluated in terms of “surface integrity” by using standard metallographic methods, microhardness testing and microprobe analysis. Interest is also directed towards the detailed characterization of the interface zones since defects at these zones could affect the electrical properties of the fabricated trimetallic components.