Low-alloyed molybdenum single crystals: preparation, structure and properties

摘要

Investigation concerns the method of preparation of low-alloyed molybdenum single crystals directly from molybdenum rods and wire, rod or foil containing the appropriate alloying metal, excluding the stage of pre-fusion of the components in an arc furnace, which is more economical than traditional method. In this way Mo-W, Mo-Ta (1,5 wt.% alloying elements of each) and Mo-Re (2 and 3 wt.%) single crystals were prepared by electron-beam zone melting. Authors discuss in more detail the structure and structural parameters of prepared single crystals. Some structural features of Mo-2 wt.% Re and Mo-3 wt.% Re single crystals are explained. Moreover the coefficient thermal linear expansion (CTLE) was measured for Mo-Re single crystals. As shown the proposed method ensures the preparation of single crystal even in single stage melt. The structural imperfections may be removed by following re-melting.