Specific Structural Phenomena in Electrodeposition of Alloys

Concerning miscibility between the metal constituents of an alloy, all types of alloys could be obtained by electrodeposition eutectic-type alloys, solid solution-type alloys, alloys with intermediate phases, and/or intermetallic compounds [1]. According to Krastev and Dobrovolska [40], self-organization phenomena during the electrodeposition of alloys, resulting in pattern and spatiotemporal structure 

4 Electrodeposition of Alloys with Periodically Changing Currents 

The experimental conditions were pulse off-times 16,80,400, and 16(X) s, duty cycle 0.2, pulse current density /on = 100 mA cm , current density during off-time /off = 0.2 mA cm, and RPM= 1400. Under such hydrodynamic conditions, a limiting current density for copper electrodeposition was /l(Cu) = 9.7 mA cm . The number of cycles (depending on the on-time and off-time) was 11022, 2204, 441, and 110, respectively, in order to obtain approximately 1.3 mm thick electrodeposits. The SEMs of etched cross sections presented in Fig. 7.32 illustrate the phase distribution obtained in the experiments. Except for the electrodeposit shown in Fig. 7.32d, which had the lowest Cu content, the electrodeposits exhibited a colunuiar structure. The Co alloy columns apparently go through the entire electrodeposit, indicating that atoms are added to existing growth sites in each phase [55]. 

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