Effect of different organic solvents on electrodeposition and wear behavior of Ni-alumina nanocomposite coatings

Nickel-alumina metal matrix nanocomposite (MMC) coatings were pulse electrodeposited from a Watt's type bath containing organic solvent and alpha-alumina nanoparticles on steel surface. The aim of this study was to investigate the effect of various organic solvents on the amount of reinforcement nanoparticles and wear resistance of the nanocomposite coatings. Six various solvents (triethanolamine, glycerol, formaldehyde, ethanol, methanol and carbamide) with fixed concentration in Watt's bath were used to pulse electrodeposition of the coatings. Zeta potential of alumina nanoparticles was measured and found to be between 4.1 and 36 my. The influence of these organic solvents on the microstructure, the amount of embedded nano-alumina, preferred orientation of the deposits, hardness and tribological behavior of the coatings was studied. The study of the microstructure and wear test showed that with changing the type of added organic solvent to the Watt's solution, the amount of embedded Al2O3 nanoparticles in the coatings increased (from 2.1 to 5.7 wt.%), and consequently, their wear resistance approximately up to 3 times increased compared with the bath without additive.(C) 2017 Elsevier B.V. All rights reserved.