The influence of synchrotron radiation-induced strain on the growth and dissolution of brittle and ductile materials

Abstract

Abstract Sodium chlorate (brittle) and sodium nitrate (ductile) crystals were irradiated by synchrotron radiation to produce samples in which one-half of a particular crystal was strained by radiation damage and the other not. The growth and dissolution kinetics of these samples were investigated using in situ laser interferometry and X-ray topography. An appreciable difference was observed in the growth and dissolution kinetics of the irradiated and nonirradiated halves. In the region of very low supersaturation, σ c = 0.32% for sodium chlorate and σ c = 0.065% for sodium nitrate, the irradiated portions of both types of crystals dissolved; simultaneously, the nonirradiated portions grew. Above the critical supersaturation, σ c , both halves grew. This defines a difference in solubility between the irradiated and nonirradiated material. The significant difference between the two critical supersaturations in the two materials confirms our earlier findings that a larger amount of elastic strain per unit volume can be introduced into brittle materials than into ductile ones. This, in turn, has a much stronger effect on both growth and dissolution kinetics. Irradiation is shown to yield pure point defect strain and not to introduce dislocations in the system. A possible mechanism by which strain influences the growth and dissolution kinetics is discussed.