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Copper corrosion in aerated water vapour has been studied as a function of temperature, relative humidity in the presence and absence of a low gamma radiation dose rate. On surface areas covered by a thin water layer corrosion ceased after ≤ 30 days by the formation of CuO on the surface of a Cu2O layer. At the locations of condensed water droplets corrosion was more extensive since the corrosion product developed porosity. Radiation accelerated the formation of Cu2O on corroded areas and increased the number and size of the more extensively corroded locations. The distribution of condensed water was the dominant feature controlling corrosion penetration.

The corrosion of a number of coarse- and fine-grained copper materials has been studied in an aerated aqueous nitric acid (100 mM) solution. The materials properties and the consequences of corrosion were characterized by scanning electron microscopy, electron back scatter diffraction and confocal laser scanning microscopy. The corrosion of the coarse-grained materials was shown to be strongly influenced by the crystallographic orientations of grains. For fine-grained materials grain boundary etching at high angle grain boundaries and grain boundary pores (for cold sprayed copper) overrode the influences of texture on the corrosion rate.

Gamma-irradiation significantly increases the corrosion potential on pure Co and the cobalt alloy, Stellite-6. To understand the radiation-induced corrosion of these materials, electrochemical studies of film formation and conversion on these metals were performed as a function of potential under both potentiodynamic and potentiostatic conditions. The oxidized surfaces were characterized by electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy. Four characteristic potential regions are identified for anodic oxidation. Comparison of the behavior of pure cobalt and a cobalt alloy provides an insight into the role of an initial air-formed chromium oxide layer on the oxidation of Stellite-6 under different corrosion conditions.