Abstract
The alumina content of nickel-alumina composites electrodeposited on a rotating cylindrical cathode in an alumina dispersed Watts solution decreased With increasing revolution rate of the cathode. The maximum size of alumina particles deposited also decreased with increasing revolution rate. These new findings on the behaviours of the deposits have been studied in detail with measurements of the size distribution both of particles in the plating solution and of the particles in the composites. The increase in the revolution rate of the cathode displaced the cumulative size distribution curve of the particles embedded in the deposit to smaller size range. The particle size on the distribution urve, which corresponds to the efficiency of transfer of dispersed alumina is inversely proportional to the revolution rate. This observation can be explained in terms of an estimated value of the Hamaker constant of 2.5×10-19[J] for the heterocoagulation between alumina and nickel.
