Radiation-induced atom separation in alloys
Annotatsiya
Abstract A mechanism of non-uniform concentration region formation in the path of collision cascades in alloys is proposed. Analysis of kinetics of recovery of the post-cascade defect distribution in the alloys shows that annealing of such a damage region can lead to redistribution of the alloy component composition: a region rich in one species of alloy components is formed in the place of a depleted zone. The atoms of one of the components preferentially return due to the significant flux of these atoms to the depleted zone. The flux is caused by difference in component atomic volumes and local stress fields produced by vacancies and interstitials in the post-cascade damage zone. The greater the difference in the atomic volumes the more effective is the formation of non-uniform concentration regions. These regions can be considered as nuclei of a new phase. The mechanism is qualitatively proved by experimentally observed regularities of phase transitions in irradiated alloys.