The WWR-K is 6-MW(thermal) light-water, tank-type reactor with thermal neutron spectrum. It is the exclusive multipurpose research reactor in the Republic of Kazakhstan. The WWR-K is owned by the Institute of Nuclear Physics of the Ministry of Energy of the Republic of Kazakhstan. The coolant is desalted water. The moderator and the reflector are desalted water and beryllium. The reactor operates on uranium dioxide that is enriched to 19.7% by 235U. The reactor is equipped with irradiation channels with the following characteristics: the thermal neutron flux density in the core center comprises 2 · 1014 cm−2s−1, whereas the fast neutron flux density (En > 0.1 MeV) comprises ~8 · 1013 cm−2s−1; in the core periphery, fluxes of the thermal and fast neutrons comprise, respectively, ~8 · 1013 and ~6 · 1012 cm−2s−1. The regular irradiation cycle length is 21 days. The annual number of cycles is ten.

Since WWR-K reactor startup, the studies of various prospective reactor materials and fuels have been carried out in its core. Since 2000, activities on in-reactor tests of fusion reactor materials have been performed at the WWR-K reactor, such as experiments on tritium release out of lithium ceramics. Tests forced development and fabrication of an installation for in-reactor studies of tritium release from various candidate materials of fusion reactor blankets in the inert gas environment of an ampoule with specimens under study. Also, a technique has been developed for assessment of the time of tritium retention in materials under irradiation.

In 2018, the WWR-K reactor facility was upgraded for studies of fusion reactor materials under irradiation, which makes it possible to carry out experiments on irradiation of specimens at vacuum conditions.

This work presents the experimental facility description and block circuit along with its general technical capacities as applied to the expected studies of tritium release of fusion reactor materials at the WWR-K reactor. The developed irradiation ampoule device is presented schematically as well. Also, the obtained results of the neutron-physical, thermophysical, and vacuum calculations for the in-reactor experiment on irradiation of fusion reactor blanket materials are given.