FABRICATION OF TRIMETALLIC STRIPS BY EXPLOSIVE CLADDING AND ROLLING

The fabrication of trimetallic composite contacts for electrical and e lectronic switches is reported. A thin layer of solder metal is explos ively cladded onto a copper plate, the resulted bimetallic strip is ro lled to a thickness of 2 mm and the cladded/rolled bimetallic is explo sively 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 soudne ss and micro- and macrostructural properties of the fabricated composi te plates is evaluated in terms of ''surface integrity'' by using stan dard metallographic methods, microhardness testing and microprobe anal ysis. Interest is also directed towards the detailed characterization of the interface zones since defects at these zones could affect the e lectrical properties of the fabricated trimetallic components.