Interfacial Reaction at the Joint between Mo-41Re Alloy and SiC induced by High-Temperature Annealing

Abstract

Interfacial reaction of metal-ceramic joints is of great interest because of their potential applicability to components operating in high-temperature environments. In this work, Mo-41Re alloy with sputter-deposited SiC coating was annealed at 1300 similar to 1500 degrees C, and the reaction at the alloy/SiC interface was investigated. On annealing at 1500 degrees C, the element Mo in the Mo-41Re alloy significantly diffused toward the SiC layer, reacted with SiC, and formed a MoC layer. The reaction resulted in the depletion of Mo in the alloy adjacent to the surface. A brittle sigma-MoRe phase that was detrimental to joint reliability, formed at a depth of 10 similar to 20 mu m from the alloy surface. After annealing at lower temperature (1300 degrees C), the sigma-MoRe phase was formed less deep (3 similar to 5 mu m), but with higher density, in the alloy. The reaction at both temperatures additionally resulted in Mo suicides and voids at the interface.