Structural?Phase transformations in metal alloys during high-dose ionic implantation

Abstract

Data on phase and structural transitions in the surface layers of metal alloys as a function of the conditions of ionic implantation (ii) are reviewed. It is noted that ionic mixing of surface-absorbed active elements from the implantational gas medium plays an important role in forming the elementary and phase composition of the ion-doped layers. The dependence of these characteristics on the ii conditions is analyzed. The formation of high-energy defect structures and the dispersion of the implanted-layer crystal structure in the strong internal-stress fields generated by the highly nonequilibrium solid solutions and in the course of phase transformation are considered. New possibilities for microstructural modification in ii are identified, with the formation of high-energy defect (including nanocrystalline), heterophase, and other phase—structural states and their combinations in ion-doped layers of metallic alloys.