Novel composite coatings containing (TiC–Al 2O 3) powder

Abstract

Electroless plating technique has been applied on steel substrate to prepare novel Ni–P composite coatings containing (TiC–Al 2O 3) powder synthesized by self-propagation high temperature synthesis (SHS). The operating conditions for plating process, such as powder content, temperature and pH were optimized. The mechanism of the co-deposition process was also discussed. The results demonstrated that the powder particle incorporation in deposited electrolessed layer depends on pH, temperature and content of powder suspended in plating bath. The maximum (TiC–Al 2O 3) incorporation (approximately 61 vol.%) could be obtained by addition of 10 g/L of powder in the plating solution operating at pH 5.5 and temperature 85 °C. The morphology of composite coatings has been investigated using scanning electron microscopy (SEM). Incorporation of (TiC–Al 2O 3) particles in deposited coating significantly improves the corrosion resistance, wear resistance and increases the hardness of deposited layer.