Ni–P alloy–carbon black composite films fabricated by electrodeposition

Ni–P alloy–carbon black (CB) composite films were fabricated by electroplating and their microstructures and properties were examined. The CB and phosphorus contents of the composite films were also investigated. The CB particles were found to be embedded in the Ni–P alloy matrix. The CB content in the deposits increased, reached a maximum value of 0.77 mass% with increasing CB concentration in the bath up to 10 g dm−3, and then decreased with a further increase in the CB concentration in the bath. Both before and after heat treatment, the composite films had higher hardnesses and lower friction coefficients than the Ni–P alloy films. Both before and after heat treatment, the friction coefficient of 0.77 mass% CB composite films was about half that of Ni–P alloy films without CB.