Characterization and selection of optimal parameters to achieve the best tribological performance of the electrodeposited Cr nanocomposite coating

In this study, Nano particles were co-deposited with chromium from a hexavalent chromium bath by the conventional electrodeposition onto steel substrate as a cathode. The main goal of this work is to improve the wear and corrosion resistance, microhardness, coefficient of friction and select the best coating condition to satisfy these parameters using combined Analytic Hierarchy Process (AHP) – Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. The dependence of the mentioned parameters was investigated in relation to the Al2O3, TiO2, SiO2 concentration in bath and particle size and it was found that the best tribological behavior improves by decreasing the particle size and increasing the particles concentration in the bath up to 10 g/l. AHP–TOPSIS method led to choose the Cr–Al2O3 nanocomposite coating achieved at 10 g/l Al2O3 content with mean particle size of 10 nm as the preferred alternative which is in good accordance with empirical findings.