Speaker
Description
The development of thermonuclear energy is one of the key areas for solving the problem of energy resource depletion in the modern world over the next 50-100 years. At the same time, special attention is paid to solving the problem of tritium production, which is one of the main types of fuel in reactors for the full-fledged maintenance of thermonuclear fusion.
For the production of tritium, it is proposed to use lithium-containing ceramics, which are a source of tritium release by capturing neutrons and forming tritium 6Li+n→4He+3T. However, during nuclear reactions of neutrons with lithium, tritium alongside several products such as helium, hydrogen and other radiolysis products are released, which worsens the strength and thermal parameters that play an important role in determination of the stability of ceramics during their operation.
The addition of magnesium oxide as a stabilizing dopant is proposed to increase the stability of ceramic structural materials used under conditions of high temperatures, pressures, and increased radiation exposure. Mechanochemical milling followed by high-temperature annealing at 1300° C was applied as the main method to initiate phase transformations accompanied by structural ordering. The aim of this work is to study the effect of modification of lithium-based ceramics by doping with magnesium oxide to improve the strength and thermal properties of lithium-containing ceramics, as well as their radiation resistance.
According to the obtained results, a direct relationship between changes in strength and thermal physical parameters and the structural disorder degree is observed. In this case, the addition of the stabilizing MgO dopant leads to the formation of inclusions in the form of the tetragonal phase MgLi2ZrO4, which leads to an improvement in the strength and thermal parameters, which occur due to an increase in interphase boundaries, the presence of which provides additional sinks for point and vacancy defects, and at the same time restrains the migration and diffusion of implanted helium in the structure. The results of the study makes it possible to recognize the promising use of MgO at concentrations greater than 0.1 M as stabilizing additives, allowing the creation of ceramics with strength, hardness and thermal conductivity, as well as resistance to radiation-induced degradation processes, significantly higher than in similar lithium-based ceramics.
This research was funded by the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (No. BR28712757 «Research in the field of creation and targeted modification of lithium-containing ceramics – promising materials for tritium propagation»).
