Vanadium alloy is considered as the first candidate material for self-cooled lithium blanket for its excellent neutron resistance、mechanical property and compatibility with lithium.In the real application,the mass transfer between vanadium alloy and liquid lithium is of great concern for its microstructure and mechanical change.Meanwhile,vanadium alloy is exposed to high neutron flux in fusion blanket environment and neutron irradiation may cause great displacement defect which may significantly change its microstructure and mechanical property,thus it is quite necessary to investigate the synergistic effect of irradiation and lithium corrosion.Given to the access difficulty of neutron irradiation source,He2+and H+ions are utilized for vanadium alloy irradiation to create displacement defect and combined with high temperature liquid lithium corrosion experiment,the synergistic effect for vanadium alloy will be studied.