Gamma Irradiation Influence on Ta Element Segregation and Mechanical Properties of Ti35 Alloy

Abstract:

Based on the highly radioactive service environment of spent fuel reprocessing, the influence of gamma irradiation on the structure of Ti35 alloy was studied by applying gamma rays at different irradiation doses, and the structure-activity relationship between irradiation-induced structure and performance was established. The results show that gamma irradiation induces a large number of defects in Ti35 alloy, and the defect density increases with the increase in irradiation dose. The rapid migration of Ti atoms in the Ti35 alloy matrix caused by irradiation results in the formation of a body-centered cubic Ta-rich second phase in the granules, and the Ta content and size of this phase further increase with the increase in irradiation dose. Gamma irradiation significantly reduces the elongation of Ti35 alloy, which is related to the deformation and interface failure mechanism dominated by Ta-rich soft phase according interface analysis. The Ti35 alloy shows ductile fracture mode before and after irradiation, and it is found that gamma irradiation significantly increases the size and density of fracture micropores by observing the fracture morphology.