Applications of disorder-induced melting concept to critical-solute-accumulation processes

A generalized version of the Lindemann melting criterion has recently been used to develop a unified thermodynamic description of disorder-induced amo rphization and heat-induced melting. This concept of amorphization as a mel ting process is based on the fact that the melting temperature of a defecti ve crystal driven far from equilibrium will decrease relative to that of it s defect-free equilibrium state. The broader view of melting provides a new perspective of damage-accumulation processes such as radiation damage, ion implantation, ion beam mixing, plastic deformation, and fracture. For exam ple, within this conceptual framework, disorder-induced amorphization is si mply polymorphous melting of a critically disordered crystal at temperature s below the glass transition temperature. In the present communication, we discuss the application of the concept to two specific cases: amorphous pha se formation during ion implantation and solute segregation-induced intergr anular fracture. (C) 2001 Published by Elsevier Science B.V.