The structure of CuCd alloys obtained electrolytically under galvanostatic conditions

Abstract

The structure of CuCd alloys obtained from an ethylenediamine electrolyte was studied in the range of current densities from D k = 0.01 to 2.0 A dm −2 and for a mean thickness of the deposited layer of 20 μm. An analysis was made of the chemical and phase compositions of the alloys, the sizes of crystallites and lattice distortions, the solubility of cadmium in sopper and the surface morphology. Depending on the current density, either single-phase alloys (α-phase) or two-phase alloys (α-phase + cadmium-enriched phase or α-phase + Cu 2Cd) are formed. The size of the α-phase crystallites decreases with an increase in current density so that amorphous alloys are obtained above D k = 0.5 A dm −2 . The maximum solubility of cadmium in copper is about 22 at.%. The structure of the alloys obtained under galvanostatic conditions is compared with that of alloys previously obtained under potentiostatic conditions.