Sputter-deposited Cu/V nanolayer films with individual layer thickness, h, varying from 1 to 200nm were subjected to He-ion irradiation at room temperature. At a peak dose level of 6dpa, the average helium bubble density and lattice expansion decreased significantly with decreasing h. The magnitude of radiation hardening decreased with decreasing individual layer thickness, and becomes negligible when h was 2.5nm or less. This study indicates that nearly immiscible Cu/V interfaces spaced a few nm apart could effectively reduce the concentration of radiation induced point defects. Consequently, Cu/V nanolayers possess enhanced radiation tolerance, i.e., reduction of swelling and suppression of radiation hardening, compared to monolithic Cu or V.

Interface Enabled Defects Reduction in Helium Ion Irradiated Cu/V Nanolayers. E.G.Fu, A.Misra, H.Wang, L.Shao, X.Zhang: Journal of Nuclear Materials, 2010, 407[3], 178-88