Development of Nanocrystalline Copper-Refractory Metal Alloys

Abstract

Precipitation-strengthened Cu-based alloys have limited use as structural materials at high temperatures due to precipitate coarsening and strength loss. We have recently shown that Curefractory metal alloys produced by various physical vapor deposition methods have stable, nanocrystalline microstructures and maintain their strength properties even when annealed at temperatures as high as 900 C for up to 100 hours. This paper presents discussions of how these alloys are processed and the resulting microstructures. X-ray and electron microscopy results will be presented to document the phase transformations that occur in these alloys and result in such exceptionally stable microstructures.