Structure and phase transformation behaviour of electroless Ni–P composite coatings

This paper addresses the structural characteristics and phase transformation behaviour of plain electroless Nix2013;P coating and electroless Nix2013;Px2013;Si3N4, Nix2013;Px2013;CeO2 and Nix2013;Px2013;TiO2 composite coatings. The X-ray diffraction patterns of electroless Nix2013;Px2013;Si3N4, Nix2013;Px2013;CeO2 and Nix2013;Px2013;TiO2 composite coatings are very similar to that of plain electroless Nix2013;P coating, both in as plated and heattreated conditions. Selected area electron diffraction (SAED) patterns obtained on the Nix2013;P matrix of Nix2013;Px2013;Si3N4, Nix2013;Px2013;CeO2 and13; Nix2013;Px2013;TiO2 composite coatings exhibit diffuse ring patterns resembling the one obtained for plain electroless Nix2013;P coating. Phase transformation behaviour studied by differential scanning calorimetry (DSC) indicates that the variation in crystallization temperature and the energy evolved during crystallization of plain electroless Nix2013;P coating and electroless Nix2013;Px2013;Si3N4, Nix2013;Px2013;CeO2 and Nix2013;Px2013;TiO2 composite coatings is not significant. The study concludes that incorporation of Si 3N4, CeO2 and TiO2 particles in the Nix2013;P matrix does not have any influence on the structure and phase transformation behaviour of electroless Nix2013;P coatings.