The effects of neutron irradiation temperature and dose on thermal diffusivity are
compared between non-irradiated and in-pile irradiated MgO samples. MgO pellets
were irradiated in-pile of the Advanced Test Reactor at Idaho National Laboratory.
Samples were irradiated at 623 and 973 K to fast neutron fluences of 1 x 1025 (1.5 dpa)
and 2 x 1025 n/m2 (3 dpa). Post irradiation examination included X-ray diffraction,
scanning electron microscopy, laser flash thermal diffusivity, and transmission electron
microscopy. The radiation induced thermophysical and structural evolution of MgO is
reported