Target material and damage

The development of spallation target system for the Neutron Science Project is proceeding at Japan Atomic Energy Research Institute (JAERI). The container of the liquid mercury target will be subjected to very intensive damage by radiation, corrosion/erosion by mercury, thermal stress and pressure wave. Test programs are planed for the development of structure material of the container. For radiation damage, irradiation data at high dose, high He/dpa and high H/dpa are obtained to simulate the effect of irradiation on the mechanical properties of the container material under spallation condition. Tensile, fatigue and fracture toughness tests are conducted under mercury. Thermal shock tests are also performed to evaluate the integrity of the container. Each of these programs described in this paper. (author)