Effect of diamond crystallographic orientation on dissolution and carbide formation in contact with liquid aluminium

Reactivity of synthetic diamond single crystals with liquid aluminium is very distinct for the different diamond faces. The {111} faces are barely attacked by liquid aluminium whereas the {100} surface atoms are easily dissolved and participate in the formation of carbides resulting in jagged {100} faces featuring a characteristic morphology which can be explained by the effect of dissolution-resistant small surface areas. By providing a third bond to the underlying atoms, these areas protect the atoms within a volume bounded by {111} faces. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.