Nickel-Chromium Alloys by Codeposition: Part I—Codeposition of Chromium Particles in a Nickel Matrix

SummaryThe wellknown high speed nickel sulphamate bath has been used to codeposit chromium particles to give high rates of electrodeposition required in forming. Electrodeposition in the presence of conducting particles generally leads to a dendritic-like growth and porous deposits. Our investigations have shown that Cr content is mainly controlled by the concentration of particles in suspension rather than the current density. The factors affecting porosity have been studied; the best method of controlling the dendritic growth at present depends on mechanical methods such as rotating cathodes with sponge covered scrapers. Several experiments have been carried out in order to elucidate the mechanism and the results suggest that low porosity in electrodeposits would be obtained if sub-micron particles were used for codeposition.