Irradiation dose and temperature effects on BCC material with dislocation based crystal plasticity

Abstract

Numerical modelling of temperature and strain rate dependent plasticity of body centered cubic (BCC) materials is carried out based on dislocation based crystal plasticity model. In view of the strong influence of radiation effects on the response of BCC materials, the constitutive equations are further extended to incorporate the effect of irradiation-induced defects. Size of irradiation defects produced (mainly dislocation loops) is mostly controlled by the irradiation temperature, whereas the defect number density is governed by the irradiation dose. The present constitutive model is introduced to predict the irradiation conditions and temperature dependent plasticity for BCC materials. The model is used to simulate the different irradiation conditions in terms of dislocation loop size and number density. To have a quantitative effect of irradiation conditions on material toughness, the Defect Induced Apparent Temperature Shift (ΔDIAT) is estimated and compared with available experimental evidence, for validation.