Joining of Refractory Metals and its Application

In this work fusion and solide state welding techniques for joining PM refractory metals are adressed. The weldability is discussed and evaluated by electron beam and friction welding experiments. EB welding experiments were performed on rolled sheets made of different Mo-based materials. While a significant decrease in the mechanical properties was found for the weldments of unalloyed molybedenum and the alloy TZM, good weldability is given for Mo41Re. A welding procedure was established and used for the manufacturing of thin walled tubes. Rotary friction welding experiments were carried out on rod material of the Mo-alloys TZM and MHC. Suitable process parameter were determined and successfully transferred for the joining of tubular TZM parts.