Preparation of Ni-W Coatings and Their Wear Resistance and Corrosion Resistance

Ni-W coatings with different tungsten content were prepared on brass substrate by electroplating. The phase composition and grain size of the coatings with different tungstate content and annealed at different temperatures were analyzed by X-ray diffraction (XRD), for determining the optimum annealing temperature of the coatings. The wear resistance and corrosion resistance of the coatings with different tungsten content were evaluated by friction and wear test and electrochemical test, respectively. The results showed that the grain size of the coatings increased with the increase of heat treatment temperature. The coatings annealed at 300℃ had relatively small grain size, which was the most suitable heat treatment temperature for Ni-W coatings. The increase of tungsten content could refine the grain size of the coatings. With the increase of tungsten content, the wear resistance and corrosion resistance of the coatings were improved.