Varying temperature irradiation experiment in HFIR

Post-irradiation examination has started and initial results are available for the varying temperature irradiation experiment conducted in the high flux isotope reactor (HFIR), carried out in the framework of the Japan–USA Fusion Cooperation Program (JUPITER project). This experiment is an unprecedented controlled irradiation experiment designed for symmetrical comparison of isothermal and temperature-variant neutron irradiation effects. This paper summarizes the irradiation experiments and initial results obtained from the post-irradiation examination of an austenitic alloy, vanadium, a vanadium alloy and copper. These preliminary results extend the trends observed in earlier, lower fluence experiments, with some effects of the low temperature phase of variable temperature irradiation on evolving microstructures.