Preparation of ceramic-intermetallics-metal three layered clad by novel hot explosive welding

Abstract

We have developed a novel welding technique for joining ceramic materials and metals. The technique composes of combustion synthesis, which is an exothermic reaction with very high temperature, and explosive welding. Layered powder bed consisting of raw material powders for TiC-Al₂O₃ ceramic composite and TiNi intermetallics was combustion-synthesized on a copper plate by using the metal heating coil. After that, the explosive was detonated immediately for welding under elevated temperature associated with the combustion synthesis. Consequently, a threelayered clad was obtained with cohesive interface between the dissimilar materials. Hardness value in the ceramics layer increased with the amounts of explosives. The rapid quenching tests using the strip specimen showed no exfoliation at the interfaces of the samples. It is suggested that TiNi with pseudo elastic effect was effective to relax the thermal stress caused between the dissimilar materials.