E. A. Pavlov, I. V. Chuprov, M. V. Nikulin, E. V. Mal’tsev, A. A. Pshenichnaya, T. F. Grigoreva,
[E. A. Pastukhov], A. P. Skuratov, N. Z. Lyakhov
ABSTRACT
The interaction between a solid inert metal (Ir) and an active liquid metal (Ga) on the mechanical activation in high-energy planetary mill was studied by X-ray diffraction and scanning electron microscopy with EDS-apparatus for high-resolution energy dispersion X-ray microanalysis. The influence of the regime of mechanical activation on the formation of intermetallic compounds GaxIry and composites GaxIry/Ir and on their solubility in various acids were investigated. Gallium, being a surface-active substance for iridium, penetrates at the grain boundaries of polycrystalline iridium particles and sharply reduces their strength. Under strong mechanical deformation during activation the contact surface area between the solid and liquid metals is greatly increased, where the intermetallic compounds are intensively formed. As a result of treatment by mixture of hydrochloric and nitric acids, iridium (~30%) from the intermetallic compounds passes into the acidic solution, forming a complex compounds HxIrCly (H2IrCl6), which, interacting with bases, can give a soluble complex salts.
KEYWORDS:
mechanochemical synthesis, intermetallic compounds, gallium, iridium, iridium complex compounds.