Growing Single Crystals of High-Purity Refractory Metals by Electron-Beam Zone Melting

Abstract

Crucible-less methods are very important and useful for melting, study and preparation of high-purity refractory metals and alloys because of the high melting points and chemical reactivity of these materials in the liquid state. The modified electron-beam floating zone melting (EBFZM) technique has been used for purification of refractory metals from both gaseous and metallic impurities and for growing single crystals. The growing processes of bicrystals of refractory metals from the melt, with desired grain boundary type and other bicrystalline parameters, have also been studied. Application of the EBFZM technique to the growth of W and Mo single crystal tubes is discussed, and the possibilities of using the EBFZM technique for preparation of highly pure refractory metals and alloys for advanced technologies are shown.