Joining ODS materials for high-temperature applications

Oxide-dispersion-strengthened (ODS) high-temperature alloys represent a unique class of powder-metallurgy-based engineering materials. They offer combinations of high-temperature strength, oxidation resistance, and hot corrosion resistance that cannot be obtained in other alloys. The alloys were initially developed for the aircraft gas turbine industry; since then, however, applications have expanded to include industrial gas turbines, equipment for handling molten glass, high-temperature furnace assemblies, and a variety of other industrial components. Internationally, the materials are also of interest for nuclear power systems (both breeder and fusion reactors) since ferritic ODS alloys exhibit both excellent swelling resistance and good elevated-temperature creep resistance. Many of these applications require that the ODS alloys be joined to either themselves or to other materials. The purpose of this paper is to review some of the techniques available for making these joints.