Effect of Electrolysis Conditions on Composition and Microhardness of Coatings with Ternary Cobalt Alloys

The process of ternary Co-W(Mo)-Zr alloys deposition on a copper substrate from pyrophosphate-citrate electrolytes in a pulsed mode was investigated. The effect of temperature, the pH of the electrolyte, and the current density on the composition, surface morphology, and current efficiency of ternary electrolytic cobalt alloys with refractory metals was studied. The resulting coatings are characterized by a uniformly developed surface without cracks, which provides a sufficiently high and reproducible microhardness. It was found that the size of the globules on the alloy surface decreases with increasing the current density up to 10 A/dm2. It was found that an increase in temperature favorably affects the current efficiency and microhardness of Co-W-Zr coatings. The regimes of the electrosynthesis of coatings by cobalt-tungsten-zirconium alloys with a given level of the surface development and microhardness were substantiated.