The driving force for recrystallization in bent single crystals of silver

Abstract

During an experimental study of recrystallization of bent single crystals of silver, in which measurements of dislocation density were made, it was found that the energy associated with the dislocations comprised but a small fraction of the driving energy for recrystallization. Experimental evidence was obtained to support the theory that excess point defects produced by the bend deformation, in particular vacancies, provide the major source of the driving energy for recrystallization under the present experimental conditions. Two annealing stages were found during which the driving energy for recrystallization decreased to values below that necessary to achieve recrystallization on subsequent heating to high temperatures. This process is called “degradation.” Specimens bent to 12% outer fiber strain or less degraded much more rapidly than specimens bent to 23% outer fiber strain. It is postulated that the vacancy-sinks are not infinite and that the longer degradation time is a measure of the time required for the excess vacancies to diffuse to the specimen surface.