A comparison of the corrosion behaviour of copper materials in dilute nitric acid. (November 2021) - Dobkowska, Anna
Abstract: 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. Highlights: Differences in corrosion behaviour of coarse and fine-grained Cu in HNO3 are shown. Crystallographic orientation of grains dominates corrosion of coarse-grained Cu. Anodic/cathodic ratio of HAGBs and grain interiors controls corrosion of fine Cu. In cold spray Cu, corrosion propagated preferentially within particle boundaries.