Microstructural interpretation of the fluence and temperature dependence of the mechanical properties of irradiated AISI 316

The effects of neutron irradiation on the mechanical properties of annealed and 20% cold-worked AISI 316 irradiated in EBR-II were determined for the temperature regime of 370 to 7600C for fluences up to 8.4 x 1022 n/cm2 (E > 0.1 MeV). At irradiation temperatures below about 5000C, both annealed and cold-worked material exhibit a substantial increase in the flow stress with increasing fluence. Furthermore, both materials eventually exhibit the same flow stress, which is independent of fluence. At temperatures in the range of 538 to 6500C, the cold-worked material exhibits a softening with increasing fluence. Annealed AISI 316 in this temperature regime exhibits hardening and at a fluence of 2 to 3 x 1022 n/cm2 (E > 0.1 MeV) reaches the same value of flow stress as the cold-worked material