Synthesis and resistance to helium swelling of Li2TiO3 ceramics

Abstract

The work is devoted to the study of the effect of helium ion irradiation on the properties of ceramics based on Li2TiO3, which have great potential as a breeding blanket in the design of thermonuclear reactors. The choice of the type of ions and irradiation doses of 1–5 × 1017 ion/cm2 is due to the possibility of modeling the processes of defect formation as a result of the accumulation of helium in the structure of the surface layer of ceramics during their operation. As research methods, scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used and the dielectric properties were studied by impedance spectroscopy. It was found that at irradiation doses of 1–3 × 1017 ion/cm2, these ceramics have high radiation resistance to structural changes, while increasing the radiation dose above 5 × 1017 ion/cm2 leads to significant changes in the properties of ceramics, which are caused by partial degradation of the surface layer of ceramics in the process exposure. As a result of measuring the strength characteristics, it was determined that the greatest decrease in the hardness of the surface layer occurs at an irradiation dose of 5 × 1017 ion/cm2. In the course of studying the dielectric characteristics, it was found that the main changes are associated with a decrease in the dielectric constant, as well as an insignificant shift of the maximum towards high temperatures, which is due to an increase in the concentration of defects in the structure of ceramics arising during irradiation.