Superconducting Transition Temperature in Martensitic Titanium-Base Transition-Metal Binary Alloys.

摘要

Quenched, martensitic, titanium-base, transition-metal-binary (Ti-T2) alloys exhibit unusually rapid increases in superconducting transition temperature, T sub c, with solute concentration. Indeed, in Ti-Mo it has been proved that T sub c is much higher than would be expected on a purely density-of-states basis. The general enhancement of T sub c in the martensitic alloys is thought to be a result of a lattice-disorder-induced 'soft-phonon' mechanism. Among the various Ti-T2 alloys, the rates of increase of T sub c with electron/atom ratio (average group number) vary inversely as the 'distance' between Ti and T2 in the Periodic Table. This is believed to be due to variation in lattice (solution) strengthening, which tends to offset lattice disorder as a promotor of superconductive electron coupling. (Author)