Solid-phase interaction in the MoNiV system at 1425 K

Abstract

The influence of vanadium on the solid-phase interaction of molybdenum in diffusion couple with nickel at 1425 K has been studied. The interaction of NiV alloys (containing 29.3–36.3 at.% of vanadium) with molybdenum has been found to produce no intermetallic compounds at the interfaces. Interdiffusion of elements in layered Ni + Mo-(24.8–48.3 at.%) V systems at 1425 K is found to result in the formation of a two-phase layer, comprising interpenetrating crystallites of the α and γ solid solution of the MoNiV system, in the diffusion zone. The concentrations of elements on crystallite boundaries are determined in this case by the position of phase boundaries on the MoNiV phase diagram. Investigation of interdiffusion in the transition zones of Ni + MoV alloy and Mo + NiV alloy diffusion couples, as well as in the layered Mo + Ni (foil, 50 μm) + V system, provides information on the structure of the isothermal cross-section of the MoNiV phase diagram at 1425 K. These results are in good agreement with information already available on the structure of this ternary system.