Interaction of tritium plasma and defects in tungsten irradiated with neutrons

Multiplier effects of tritium plasma and neutron irradiation on microstructural evolution in tungsten were investigated using computer simulations based on a rate theory. The effects of irradiation temperature and dissociation energy of tritium-vacancy clusters on the interaction between tritium and defects were also investigated. At the lower temperature (473 K), vacancies trapped tritium to form tritium-vacancy clusters, which grew rapidly. When the irradiation temperature increased to 873 K, however, it was difficult for a tritium-vacancy cluster to absorb a new tritium, and thus, the concentration of tritium-vacancy clusters was about eight orders of magnitude lower than that at 473 K.