Corrosion behaviour of electroless Ni–P–TiO₂ nanocomposite coatings using Taguchi

Abstract

This paper reports an experimental study of corrosion characteristics of electroless Ni-P-TiO 2 nanocomposite coatings. Coating process parameters are optimised for maximum corrosion resistance based on L 9 Taguchi orthogonal design with four process parameters, namely, concentration of nickel source solution, concentration of reducing agent, concentration of TiO 2 powder and bath temperature. Corrosion behaviour of the electroless Ni-P-TiO 2 nanocomposite coatings was evaluated in 3?5 wt-%NaCl aqueous solution using polarisation technique. Scanning electron microscopy and energy dispersive X-ray spectroscopy analysis were used for studying surface morphology and chemical composition of the electroless Ni-P-TiO 2 nanocomposite coatings. The results showed that incorporation of TiO 2 in coating causes an increase in corrosion resistance and improves surface morphology. Finally, optimum conditions were achieved as follows: concentration of nickel source solution, 50 g L 21 ; concentration of reducing agent, 10 g L 21 ; concentration of TiO 2 powder, 10 g L 21 ; and bath temperature, 85uC.

Characterization and performance evaluation of Cu-based/TiO2 nano composites

“…It was observed from the investigations made by Hosseini et.al and Rajesh et al 13 , 29 that the corrosion rate of pure copper and copper coated with TiO 2 were higher compared to Cu/Al 2 O 3 composites. Ajeel et al 30 confirmed that the reinforced copper alloy with 3 wt.% of Al 2 O 3 and TiO 2 has a lower corrosion rate than reinforced copper alloy reinforced with 1.5 wt.% of Al 2 O 3 and TiO 2 .While the reinforced alloys with 1.5 wt.% of Al 2 O 3 and TiO 2 has lower corrosion rate compared to the copper alloy. Raghav et al 31 studied the corrosion of copper –TiO 2 nanocomposite coatings on steel.…”

Crystallization and electrochemical corrosion behaviors of nanometer amorphous Ni-P alloys

“…presents the amorphous structure of the Ni-P alloy, which was analyzed by XRD. Only one broad peak around 2θ = 45°was observed, indicating the complete amorphous character of the Ni-P alloy [26][27][28][29], as shown in figures 1(a)-(c). With an increase in the heating temperature, both the number and the strength of the Table 1.…”

Surfactant-Free Electroless Codeposition of Ni–P–MoS2/Al2O3 Composite Coatings

“…The incorporation of solid particles into the matrix could remarkably improve the mechanical and physiochemical properties of composite coatings. For example, hard particles such as Al 2 O 3 [4,5], SiC [6,7], SiO 2 [8], TiO 2 [9], and diamond [10] enhance the hardness and wear resistance of composite coatings. Solid lubricant particles such as MoS 2 [11,12], PTFE [13], and BN(h) [14] lower the frictional coefficient of composite coatings and consequently reduces wear loss.…”