The microstructure and hardness changes of neutron irradiated weld joint of vanadium alloy

Effects of neutron irradiation on YAG laser welded V–4Cr–4Ti alloy were irradiated in High Flux Isotope Reactor (HFIR). The samples were irradiated in Li environment at 723 K and 873 K up to the dose of 3.7 dpa. After the irradiation, the microstructure and Vickers hardness of the welded samples were compared of the base metal, which were simultaneously irradiated at the same irradiation cycle. At 723 K, very high density of dislocations was formed. But prominent Ti(CON) formation, which was commonly observed in He gas and vacuum environment condition, was not detected