Preparation and wear resistance of electrodeposited Ni-W/diamond composite coatings

Ni-W/diamond composite coatings were obtained by electrodeposition from a Ni-W plating bath containing suspended diamond particles. The influences of plating parameters including diamond concentration in the plating bath and stirring rate on the coating composition, deposition rate, morphology, microhardness and wear behavior of electrodeposited Ni-W/diamond composite coatings were evaluated and compared with that of electrodeposited Ni-W coatings. This study reveals that diamond particles can be successfully codeposited and uniformed distributed in the electrodeposited Ni-W matrix. The maximum level of incorporation of diamond particles, about 21.1 vol.%, is obtained at a bath loading of 1 g/L and at a stirring rate of 180 rpm. The incorporation of diamond particles alters the chemical composition of electrodeposited Ni-W matrix, increases the microhardness of the coatings and significantly increases the wear resistance of the coatings.