Effect of Ni content and brazing temperature on the self-joining of ZrB2-SiC

Pd-Co-Ni filler alloy was adopted to braze ZrB2-SiC to itself. The reliable ZrB2-SiC joints were obtained. The effects of Ni content and brazing temperature were investigated on the microstructure and properties of the ZrB2-SiC joints using SEM and four-point bending method. All the joints consist of diffusion zone in ZrB2-SiC ceramic, Pd-Si phase, Co-Si phase, and Ni-Co solid solution. During the brazing, Ni and Co can solute into each other, a certain control over the reaction between SiC from the ceramic and Co from the brazing alloy was obtained, which was beneficial for the joint strength.