Morphology Control of Dy-Ni Alloy Films by Electrochemical Displantation

The simultaneous control of morphology of Dy-Ni alloy was achieved by selective anodic dissolution of Dy in a molten (0.50 mol %) system at 700 K. The electrochemically formed films, about 20 μm thick, were transformed to porous and Ni films, depending on the applied potential. Larger pores were formed when the applied potential was more positive. The rapidity and the pore-forming mechanism of the process are suggested to be closely related to the existence of the grain boundary in the alloy because the transformation reaction was very slow for the annealed electrode.