Abstract:
The paper is devoted to the study of the influence of variation of ZrO2 ceramics grain sizes on the resistance to radiationinduced swelling under irradiation with low-energy Не2+ ions. The choice of ZrO2 ceramics as objects of research is due to
high levels of mechanical strength and hardness, as well as low rates of thermal expansion, which eliminates the effects of
thermal expansion and destruction when operating at high temperatures, as well as good insulating properties, which makes
it possible to use these ceramics both as radiation-resistant materials in nuclear energy in the manufacture of inert matrices
of dispersed nuclear fuel, and as a basis for creation of fuel cells for the production of hydrogen. During the studies of the
influence of mechanochemical grinding conditions on the change in dimensional factors in ZrO2 ceramics, it was found that
increasing the grinding speed from 300 to 900 rpm does not lead to the initiation of polymorphic transformation processes
of the m-ZrO2 → t-ZrO2 type, which are also not initiated during thermal annealing of samples at a temperature of 1500 °C,
the choice of which was due to thermal relaxation of structural deformation distortions caused by mechanochemical grinding
during grain crushing. In determining the influence of size effects (dislocation strengthening) on the resistance of ZrO2
ceramics to radiation-induced swelling under high-dose irradiation with He2+ ions, it was found that a decrease in grain size
by 2.5 – 3 times leads to an increase in resistance to swelling and softening by 1.5 – 2 times. Moreover, for ZrO2 ceramic
samples obtained at grinding speeds of 700 – 900 rpm, strengthening is not only due to dimensional factors, but also to the
structural ordering of the crystal lattice, due to thermal relaxation of residual mechanical stresses.
