Sealing Metal and Ceramic Parts by Forming Reactive Alloys

Metal and ceramic parts are sealed by introducing a molten solder or by inserting a thin sheet of metal that will form a reactive alloy. A wide choice of materials can be used, including many that seal at high temperatures with little metallic evaporation. Materials can be used that can be predegassed at temperatures considerably above those used for final sealing. The seals can be made in vacuum or in an inert gas. The parts can be stacked one on the other so that a multiplicity of seals can be made at the same time. By using a metal such as titanium, and ceramic parts having an expansion characteristic similar to that of titanium, seals can be made that are strong and can operate for many hours at temperatures as high as 800°C.