Thermodynamics and kinetics of phase transformations induced by ion irradiation

Abstract

The thermodynamic and kinetic aspects of ion-irradiation-induced phase transformations in intermetallic compounds are reviewed. The different mechanisms for supplying the thermodynamic driving force for such transformations are discussed. The free energy of an irradiated material can be gradually elevated above that of a metastable state by the accumulation of lattice damage through the production of vacancy—interstitial defects, anti-site defects, and dislocations, or quickly elevated by the formation of a thermal spike in the collision cascade. The final state of the irradiated material will ultimately be determined by kinetic constraints in its transformation to lower-energy metastable and equilibrium states.