EFFECT OF HELIUM AND FISSION NEUTRONS ON THE TENSILE PROPERTIES OF V-5Ti

Tensile specimens of vanadium alloy V-5Ti, doped with 100 appm 10 B, were irradiated to a fast fluence of 4.2 × 10 25 m -2 (E > 0.1 MeV), corresponding to 4.5 dpa, and a thermal fluence of 1.9 × 10 25 m -2 . During irradiation, the specimens were exposed to Na at the temperatures 490, 580 and 670 °C. Reference specimens were also exposed to Na at these temperatures. Results of tensile tests, performed at temperatures equal to the respective annealing and irradiation temperatures, showed that at 580 and 670 °C neither displacement damage nor the generated He, due to transmutation of 10 B, had much influence on the tensile properties of the alloy. At 490 °C irradiation produced defects increased the strength properties and decreased the ductility by about 50 %.