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Electroless cobalt films were deposited from a neutral pH glycinate solution without additives using morpholine borane (MB) as a reducing agent. The rate of deposition rises with increase in concentration of solution components (Co ions, MB and glycine), and pH. The efficiency of cobalt discharge increases when the deposition is performed from the Co(II) complex with glycine. XPS data indicate that boron and oxygen are incorporated into the cobalt films. Two forms of boron (elemental and its oxide) were detected in the electrolessly deposited cobalt films. [ABSTRACT FROM AUTHOR]

Data are reported on the successful metallisation of cubic boron nitride by chemical reduction of solutions containing nickel and cobalt ions. The processes of growth of these two types of films differ substantially from each other. While in cobalt plating no screw-like dislocation mechanism film growth is observed, in nickel plating growth is by a screw-like dislocation mechanism. The titanium film deposited as a pretreatment on grains of cubic boron nitride does not influence the rate and structure of subsequent cobalt and nickel deposition. Thus, the metallised super-hard material obtained is useful for embedding into composite materials for the production of abrasive materials. [ABSTRACT FROM AUTHOR]

Cobalt-phosphorous (Co-P) was coated in alkaline solution on the E-glass fiber/fabric over a range of coating time (0-30 minutes, in intervals of 5 minutes) and temperature (50-90°C, in intervals of 10°C). The effects of coating time and temperature on the structural, compositional, morphological, thermal and magnetic properties of Co-P coated glass fiber/fabric were investigated by X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential thermal analysis (DTA), surface area and vibrating sample magnetometer device (VSM). The X-ray diffraction studies exhibit that the intensity of cobalt (Co) peak increases with increasing the coating time and temperature. The EDAX results also reveal that the Co content is high and phosphorous (P) content is low at the higher coating time. However, the Co and P content both are high at the higher coating temperature. The surface morphology of the Co-P coated fiber/fabric was evaluated by SEM. From TGA it is evident that the Co coating increases the thermal stability of glass fiber. The magnetic properties of Co coated glass fiber increases with an increase of coating time. The bath temperature of 75°C, 15-20 minutes deposition time, pH of 8.5 and stabilizer concentration of 25 g/l are the optimum conditions to get a good and uniform coating of Co on the glass fiber. Carbon nanotubes (CNTs) were successfully coated on the Co-coated glass fiber at a temperature of 700°C by chemical vapour deposition. The CNT coated glass fiber/fabric was characterized through SEM, transmission electron microscopy (TEM), atomic force microscopy (AFM), Raman spectroscopy, surface area, electrical conductivity, and so forth. Finally the performance of CNT coated glass fiber was evaluated through the measurement of modulus in the composite structure. [ABSTRACT FROM AUTHOR]

The electrochemical behaviour of Co2S3 layers deposited on glassy carbon and ABS plastic from colloidal Co(III) compound solution was investigated by cyclic voltammetry and X-ray photoelectron spectroscopy, Auger electron spectroscopy, XRD techniques in Watts Ni electroplating and Ni2+ free background electrolytes. On the basis of experimental data, it was assumed that Co2S3 converts into NiS when it is cathodically polarised at E≈-0·2 V (SHE) in the Watts electrolyte. During this process, the sheet resistance of the layer decreases from ∼3 × 109 to ∼3 × 103 ࡎ □-1. This change goes on with the direct participation of Ni2+ ions in the electrolyte and this is probably of crucial importance for the following electrodeposition of metallic Ni initiated at more negative potentials. Contrary to Cu2–xS and Bi2S3, the layer of Co2S3 cannot be electroreduced to metallic Co in the Ni2+ free background electrolyte. [ABSTRACT FROM AUTHOR]

The use of cobalt based alloys in micro-electromechanical systems (MEMS) applications seems feasible and promising as these materials are compatible with both planar and bulk technologies involved in MEMS processing. Co–Ni, Co–Mo and Co–Ni–Mo alloys can fulfil the demand for new materials in the MEMS sector especially in the magnetic actuation field. The route to obtain these alloys must take into consideration the plating bath design, the deposition parameters and the ex situ characterisation of the deposits. A continuous feedback study based on these items allows tailoring the deposit properties until deposit optimisation is achieved. This optimisation is not only focused on finding out the more appropriate mechanical and magnetic properties, but on achieving adherent, uniform, low stressed electrodeposited layers. [ABSTRACT FROM AUTHOR]