In this paper, the effect of tow thermal sprayed interlayers in torch brazing of WC based cermet to steel is investigated. The interface cermet/brazing/steel was characterized by SEM, EDS and XRD. Microhardness measurements and shear test were also done.Preliminary experimental results have shown that good bonding between cermet/brazing/steel was achieved and no voids were detected in the brazing junction. The use of the interlayer promotes the formation of interdiffusion zone, which possessed positive effects on the bond strength of the brazing joint. In the case of brazing without interlayert, this interdiffusion zone is minimal.Having performed line and surface micro analyses of various zones, post-brazing diffusions of Co and Ni and other elements were determined. The hardness distribution in microhardness measurements on this zone confirms the existence of element diffusion.
