Electroless Ni–P–SiC composite coatings with nanoparticles

Electroless nickel (EN) coatings have been widely used in the chemical, mechanical and electronic industries because of their wear and abrasion resistance and corrosion resistance. Co-deposition of solid particles into coatings can further improve certain properties, thus enhance their performance. EN–SiC coatings are recognized for their hardness and wear resistance and are considered as a replacement for hard chromium in the aerospace industry [1,2].Hard particle-containing deposits (NiP/X, X=SiC, WC, Al2O3, Si3N4…) have been developed when the main requirement for the composite coating is wear resistance [1]. Among these coatings, the combination NiP–SiC has proved to be the most cost-effective and best-performing combination .Most studies concerning NiP-hard particle systems are performed using micron-sized particles and some commercial processes exist to obtain such composites. However, the development of nanotechnologies has raised the interest on the metal matrix nano-composite coatings because of their unique mechanical, magnetic and optical properties [3].In this work, the polarization and electrochemical impedance tests is also used to analyze the corrosion behavior of EN and EN composite coatings