摘要 |
The common feature of forming an instantaneous and tenacious oxide layer, classically defines a group of metals as "difficult-to-electroplate"¹. An industrial process for the electro deposition of nickel on to aluminium, using high-speed (turbulent) electrolyte flow between conforming electrodes in proximity. Using HR-TEM nickel is deposited on the pre-existing metal-oxide (MO) layer, for example, AI2O3, TiO2. Cr2O3 layer. During the start-up phase preferably a few minutes prior to plating film thickening occurs, and conditions are created for effective nickel plating: the elevated electrolyte temperature increases thermal diffusion of (A1³+/O²-) ions; turbulent flow places fresh electrolyte at the surface, increasing the chemical potential that becomes a further driver for the ionic diffusion. This film growth is similar to anodizing. |