ELECTROCODEPOSITION AND CHARACTERIZATION OF NICKEL-TITANIUM CARBIDE COMPOSITES

Dispersion-strengthened nickel was produced by an electrocodeposition technique using a nickel fluoborate suspension. The effects of particle concentration in the bath, current density, pH and temperature on volume percentage incorporation of TiC particles in the composite were studied. The hardness, wear resistance and oxidation behaviour of the composite in the as-plated and annealed state were also examined and compared with those of nickel deposits. It was found that the volume percentage incorporation of TiC particles in the composite increased with increasing TiC content in the bath and with increasing current density. An optimum TiC incorporation (13 vol.%) was possible by operating the bath containing 30 g l(-1) of TiC particles in suspension at 5.0 A dm(-2), at pH 3.0 and at 50 degrees C. The hardness and wear resistance of the composite were found to be more than twice those of the electrodeposited nickel. The results of oxidation studies reveal that the composite oxidizes at a faster rate than nickel deposits and showed poor resistance to oxidation in the temperature range investigated.