Role of the gas cavity evolution in high-temperature radiation embrittlement of materials

High-temperature radiation embrittlement (HTRE) has been investigated by theoretical and experimental methods. Computer calculations show that the blister system filled with an unsoluble gas separates during annealing into two parts: in system one internal gas pressure compensates the surface tension; system two, nearly a vacancy system, rapidly disappears during annealing. The nonmonotonous character of blister system evolution leads to a nonmonotonous dependence of grain body strengthening, and hence, HTRE on test temperature. Experimental dependences of material ductilities on test temperature for different temperatures that supported predicted effects have been obtained. Blister initiation and growth supression permits to reduce HTRE