Composite layers in Ni–P system containing TiO2 and PTFE

Abstract

Composite Ni–P–TiO2 and Ni–P–TiO2–PTFE layers were prepared by simultaneous electrodeposition of nickel and titanium dioxide (anatase) with an addition of polytetrafluoroethylene on a copper substrate from a solution in which TiO2 and PTFE particles were suspended by stirring. The electrodeposition was carried out under galvanostatic conditions at a temperature of 293K and current densities of j=5 and 30A/dm2. The phase composition of the layers was investigated by the X-ray diffraction method. The surface morphology of the layers was examined by means of a metallographic microscope, a scanning microscope and a morphometric Supervist system. The percentage volume fraction of TiO2 and PTFE as composite components and also their stereometric parameters were determined. It was found that the presence of PTFE has an effect on reduction of the embedded TiO2 mean area in the Ni–P–TiO2–PTFE layers in comparison with the size of TiO2 grains in the Ni–P–TiO2 layers.