Crystallographic dissolution of high purity aluminium

E.V. Koroleva, G.E. Thompson, P. Skeldon, B. Noble
2007 Proceedings of the Royal Society A  
Alkaline etching of high purity aluminium has been examined using the complementary techniques of scanning electron microscopy and atomic force microscopy. Provision of specific grain orientations, generated by zone melting, has revealed dissolution rates of individual grains which decrease in the order {334}O{225}O{119}. Further, the faceting of the {334} grain, which has an orientation close to (111) , reveals the crystallographic nature of alkaline etching of high purity aluminium, with the
more » ... luminium, with the limited presence of discrete cathodic sites. For the {119} grain orientation, distinct faceting is replaced by a cellular texture that is elongated in the h120i direction. The {225} grain reveals cells elongated in the h111i direction, with step-like features present across the surface. These step features are explained by dissolution along preferred crystallographic directions to reveal facets of low-energy planes of appropriate separation and associated steps.
doi:10.1098/rspa.2007.1846 fatcat:mawy6tliv5aivmu3x3ltakqqdi