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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]

Electrochemically deposited composite coatings are of interest nowadays owing to the flexibility of the deposition process and to the increasing demand for highly wear resistant composite coatings. In electrochemically deposited coatings, a second phase such as fine tough particles is incorporated in the coating matrix to improve the surface mechanical properties. In the present work, the surface mechanical behaviour of cobalt and nickel coatings with dispersion of chromium oxide in the matrix is reported. The effect of heat treatment of these coatings on the surface mechanical properties is also studied. The surface microhardness and wear loss due to rubbing abrasion are studied before and after heat treatment in the range of 100 - 600 ° C and are reported for both systems. The composite containing 12 vol.-% chromium oxide (Cr[sub 2]O[sub 3]) in a cobalt matrix and heat treated at 500 - 600 ° C was found to exhibit high abrasive resistance. This is attributed to the formation of a glass-like layer found in the cobalt matrix. The coatings are found to be highly adherent and uniform and suitable for high temperature applications. [ABSTRACT FROM AUTHOR]