Mechanical properties of irradiated spinel ceramics

The effects of grain size on the nanomechanical properties of Ar-irradiated magnesium-aluminate spinels was studied. Spinel single crystals and ceramics of different grain size varying from ∼1 μm up to few tens of micrometers were used in the experiments. The measurements were performed in both grain centers and grain boundaries and point to rapidly disappearing differences between bulk and boundaries in irradiated ceramics. The stress-induced hardening has been observed as well. This last effect depends on the grain size of the irradiated material and may serve as an indicator of the stress evolution in the irradiated samples.