Electrocodeposition of Nickel−Diamond and Cobalt−Chromium Carbide in Low Gravity

Abstract

Codeposition of particles and metals was studied under low-gravity conditions. Ni−diamond and Co−chromium carbide coatings were investigated. Experiments were run aboard two sounding rockets, each providing 7 min of 10-4g, and one shuttle mission providing 4 h of deposition. Reduced gravity proved to eliminate sedimentation and edge effects and promote easier particle dispersion in the electrolyte, yielding uniformly distributed particles in the metal matrix. Large nonconducting diamond particles were codeposited in higher volume percents as opposed to bench experiments. The trend was opposite for particles of ≤1 μm size with fine chromium carbide particles depositing in higher volume percent in 1g than low g.