No abstract

The given study overview the results obtained for Co-W alloys electrodeposited from gluconate bath. Namely, the influence of different parameters (the concentration of the bath components, pH, temperature, cathodic current density, volume current density, hydrodynamic conditions, insoluble and soluble anodes) on the rate of electrodeposition and microhardness of the coatings has been investigated. The given research determine the conditions ensuring high deposition rate, microhardness and bath efficiency. It was shown, that the deposition rate, tungsten content and microhardness reach the maximum values at pH 6.5, regardless on the concentration of bath components. Also, it was detected the macroscopic size effect of microhardness, which is linked to the fact that for a fixed cathodic current density microhardness depends on volume current density. In addition, different anodes (Pt, graphite, W and Co-W) were investigated to reveal the anode influence on reaching the maximum values of the current efficiency and microhardness.

The paper reports on a study regarding the structure of composite layers obtained by electrochemical deposition. The depositions were achieved in a bath formed of a mixture of aqueous solutions of iron salts (iron chloride), cobalt (cobalt sulphate) and solid particles of silicon carbide (SiC) in suspension. Following the electrochemical deposition on composite structures are formed as a thin layer with a metallic matrix (FeCo alloy), reinforced with hard particles of SiC. The structure of the composite layer is uniform and very fine, with crystalline granules under 500 nm. The electrochemically deposited FeCo alloy representing the metallic matrix of the composite layer has a high micro-hardness (864 HV), superior to the same alloy obtained by casting.