Patent ID: 11654504

Abstract:
A solid-state bonding method sandwiches an intermediate layer between a pair of refractory metal members to form a composite bonding assembly. This sandwiching can be repeated with multiple refractory metal members. The intermediate layer is substantially uniform of at most 75 μm thickness and composed of a material that is soluble and diffusive in the refractory metal members, such as any of carbon, silicon, chromium, iron, cobalt, and nickel. Compressive pressure is applied, and the assembly is heated to a specified elevated temperature of at least 1280° C. The applied pressure and elevated temperature are maintained until the intermediate layer has dissolved surface oxides and asperities in the refractory metal members and has completely diffused into the refractory metal to create a seamless refractory metal bond. The pressures and temperatures needed are much lower than those required in direct diffusion bonding of refractory metals.