The role of point defects in the swelling and elastic modulus of irradiated cubic silicon carbide

Abstract

A molecular dynamics study has been performed to investigate the role of point defects in volumetric swelling and elastic modulus of irradiated 3C-SiC in the low and intermediate temperature regime. It is found that different kinds of point defects have distinctive effects on the swelling and Young’s modulus. The vacancies have the negligible influence on volumetric swelling while significant on the Young’s modulus. However, the value of volumetric swelling and the change in Young’s modulus due to the formation of other point defects vary with defect concentration exponentially which we are interested. Furthermore, it is indicated that the relation of the swelling of 3C-SiC and the contribution of point defects is independent on the temperature. During the tensile test, however, the role of carbon interstitial in Young’s modulus would be enhanced by temperature. Finally, an approximate model to estimate the antisite defect concentrations in irradiated 3C-SiC is presented.