A new method using synchrotron-radiation topography for determining point-defect diffusivity under hydrostatic pressure

Abstract

An experimental method for determining the diffusivity of point defects as a function of hydrostatic pressure has been developed by using synchrotron-radiation topography. In this method, the diffusivity can be obtained from in situ observations of dislocation climb under hydrostatic pressure. The climb motion of dislocations is caused by a rapid change in temperature which introduces supersaturation (or undersaturation) of the point defects. The method has been applied to ice, and diffusion coefficients of self-interstitials were successfully determined up to 100 MPa.