Effects of neutron irradiation on the mechanical properties of magnesium aluminate spinel single crystals and polycrystals

The effect of fast neutron irradiation on the mechanical properties of magnesium aluminate spinel single crystals and polycrystals, such as bending strength, fracture toughness, Young's modulus, and hardness, was summarized based on the reported data. Essentially, the changes in these properties are dependent on the nature and concentration of neutron-irradiation-induced defects. Furthermore, the efficiency of damage accumulation is known to be dependent on temperature. Spinel shows superior resistance to the formation of defect aggregates, and the recombination of point defects occurs efficiently under neutron irradiation; therefore, the change in mechanical properties is not critical, up to very high neutron fluences, and the spinel maintains its structural integrity.