Codeposition of Wear-Resistant Particles with Chromium.

摘要

Inclusion of particles in deposits was achieved by adding any of a number of monovalent cations to the chromium bath such as T1, Ce, Na, NH and Li. Efforts to include particles from standard chromium baths over a wide range of plating conditions were not successful. Under the plating conditions developed all particles that were added to the bath were included from a few tenths to 5 wt. % in chromium deposit without excessive loss of properties. Particles included were diamond, borides, carbides, nitrides, oxides, metals, graphite, and a sulfide. The more conductive materials were more easily included. A bath-life test using additives and particles was run for thousands of ampere-hours per liter of solution with good bath performance. Wear tests of deposits having included particles indicated Improved wear-resistance. A caliber 0.30 tube was plated with chromium having included particles which had good particle distribution throughout the bore. Deposits of cadmium and zinc with included hard particles showed improvement in wear-resistance. (Author)