Effect of temperature history on swelling behavior of V-Fe binary alloy irradiated in a fast reactor Joyo

Abstract

An on-line instrumented material irradiation rig (MARICO-II) was used for investigating temperature history effect for void swelling behavior in V-Fe binary alloys irradiated at a fast rector, Joyo. Neutron irradiation were performed at 477C with 7.5 dpa in the temperature control capsule (TC capsule) and at 482C maximum temperature with 20.4 dpa in the conventional capsule with monitoring temperature. In the TC capsule, voids was formed and distributed homogeneously, on the other hand a lot of tiny void formation or bimodal void distribution were observed in the conventional capsule, The void swelling rate of V-Fe alloys irradiated in the TC capsule was larger than that in the conventional capsule and it is caused by the imbalance of point defect flux to sink due to void nucleation at the low temperature transient regime in start-up and shutdown period of each cycle in neutron irradiation, that is temperature history effect for swelling behavior of V-Fe binary alloys during neutron irradiation.

Keywords

• Vanadium alloy
• Neutron irradiation
• Temperature history
• Microstructural evolution
• Irradiation technology