Investigation of the Structure and Properties of Molybdenum-Columbium Alloys in the Single-Crystal State (Issledovanie Stroieniya I Svoistv Splavov Sistemy Molibden-Niobii V Monokristallicheskom Sostoianii0.

摘要

The purpose of the investigation was to obtain single crystals of alloys of refractory metals free from interstitial impurities which reduce the ductility of the metal. The system molybdenum-columbium was chosen in various M0-Cb ratios, from pure columbium. The starting material for the preparation of the alloys were vacuum melted rods of molybdenum and columbium which were melted together in the apparatus for the zone melting by electron beam. The single crystals of the alloys were obtained by two passes of the molten zone made in both directions, the last pass being made away from the original Mo-Cb rods. It was found that only by using single crystals of Mo and Cb was it possible to obtain single crystals of alloys with a high concentration of the second component. The change in hardness and electroresistance was a function of the composition, similar to that in polycrystalline alloys, the hardness being greatest at the 50-50 composition. X-ray diffraction analysis disclosed a mosaic structure of the single crystal alloys.