Microstructure and properties of Ni–Co–TiO2 composite coatings fabricated by electroplating

Abstract

Ni – Co coatings are widely used due to their unique mechanical properties, high anticorrosion properties, good thermal stability and special magnetic properties. Ni – Co – xTiO 2 ( x = 0–20 g/L in the electrolyte) composite coatings were fabricated by electrodeposition on mild steel. The effect of TiO 2 concentration on the microhardness, surface morphology and tribological behaviour has been studied. The results show that, comparing with pure Ni – Co coating, both microhardness and wear property of the Ni – Co – TiO 2 composite coatings were significantly improved. The microstructure and properties for the Ni – Co – TiO 2 composite coatings were varied following with the TiO 2 concentration. The mechanism of mechanical property improvement was also discussed.