Technological Development for High Performance and Composite Single Crystals of Refractory Metals

Abstract

For the wider utilization of single crystals of refractory metals such as molybdenum and tungsten, development of high performance and/or composite single crystals is necessary. For this purpose, first, we developed new methods to control the crystallographic orientation of the single-crystalline molybdenum and to produce a multi-layered single crystal of molybdenum by means of secondary recrystallization. Second, we established fundamental conditions to braze single-crystalline molybdenum alternatively to single-crystalline molybdenum or to carbon-ceramics, respectively, by using Mo-40%Ru alloys or by palladium.