Influence of Different Interlayers Metals on Properties of Diffusion Bonding Joint of Tungsten to Copper

Ti foil and Ni foil interlayers were selected for the bonding of tungsten to CuCrZr alloy. The effects of bonding temperature on the microstructures and shear strength of the joints were performed. The interfacial bonding mechanism was studied through microanalysis. The results show that Ti foil was transformed into liquid solution and extruded mostly out of the bonding zone at 980°C, the strength of the joints can reach 136MPa due to the chemical and mechanical interfacial bonding. Ni foil was used for bonding of tungsten to copper alloy, the EDS analyses shows that the solid solution Ni(W) and the intermetallic compound NiW2 form in the diffusion layer at 920°C.