Phase Stability of Crystalline and Amorphous Phases and Formation of Nanostructure in Zr-Pd and Zr-Pt Alloys Under Electron Irradiation

Abstract

AbstractElectron irradiation induced phase transition behavior of Zr-Pd and Zr-Pt alloys was investigated focusing on phase selection in crystallization by thermal annealing and electron irradiation. Nano quasi-crystalline (QC) phase was formed by thermal crystallization in Zr66.7Pd33.3 and Zr80Pt20 alloys, while nano two-type f.c.c. super-saturated solid solutions were formed by irradiation induced crystallization at 298K. In Zr66.7Pt33.3 alloy, polycrystalline Zr5Pt3 and Zr9Pt11 phases transformed to two-type f.c.c. nano-crystalline phase through an amorphous state by crystal-to-amorphous-to-crystal (C-A-C) transition during electron irradiation. Nano-composite phase composed of f.c.c. super-saturated solid solution and residual amorphous phase was stable rather than an amorphous single phase, thermal equilibrium crystalline phase and quasi-crystalline phase under 2.0MV electron irradiation at 298K, resulting in the formation of nano-composite structure by irradiation induced amorphization and crystallization.