Application of EPR spectroscopy method for comparative analysis of structural damage accumulation kinetics in two-phase lithium-containing ceramics

The aim of this study is to determine the differences in the damaged layer degradation kinetics in two-phase lithium-containing ceramics based on Li 2 ZrO 3 and Li 4 SiO 4 compounds in the case of irradiation with protons and helium ions, simulating the gas swelling and blistering processes, as well as the accumulation of radiolysis products in the damaged layer. During the conducted studies it was established that in the case of proton irradiation, the dominant role at fluences of 10 15 –10 17 cm −2 is played by oxygen vacancies, the change in the concentration of which upon reaching critical values causes a decrease in the thermophysical properties, and disordering of the damaged layer. In this case, the accumulation of radiolysis products in the form of HC 2 – and Zr 3+ -defects in the structure of the damaged layer is observed at fluences of 5 × 10 17 cm −2 , while when irradiated with He 2+ ions, the formation of these types of HC 2 – and Zr 3+ -defects is observed at a fluence of 10 17 cm −2 . Comparison of the concentration dependences of defects in the damaged layer on the atomic displacement value under irradiation with protons and He 2+ ions revealed that the formation of oxygen vacancies under irradiation with He 2+ ions is more intense than in the case of irradiation with protons, which in turn results in more pronounced processes of accumulation of radiolysis products in the case of high-dose irradiation. • Comparative analysis of structural damage accumulation kinetics in two-phase lithium-containing ceramics. • EPR spectroscopy method for comparative analysis of structural damage accumulation kinetics. • Comparison of kinetics of change in concentration of various defects from the damage degree. • Results of the concentration of various defects in the damaged layer depending on the irradiation type.