Tribology Study of Pulse Electrodeposited Ni-B-SWCNT Composite Coating

Abstract

The wear resistance performance of Ni-B-single-walled carbon nanotube (SWCNT) composite coatings produced by impact electrodeposition on a mild steel substrate has been investigated. After electrodeposition, all samples were characterized by x-ray diffraction (XRD) anlayais, scanning electron microscopy (SEM), and other measurements. The mechanical behavior of the coatings was investigated by nanoindentation and abrasion testing. The worn surfaces were also analyzed by SEM, energy-dispersive spectroscopy (EDS), and three-dimensional (3D) profilometry. The tribological properties of the composite coatings were investigated by using Al2O3 balls in dry shear linear wear tests at load of 2 N, room temperature, and humidity of 45%. It was observed that the self-lubricating effect of the SWCNTs and NiO layers formed during wear improved the wear resistance of the coating. The coefficient of friction decreased from 0.51 to 0.28 for the coating produced with a SWCNT concentration of 0.6 g/L. The results obtained show that SWCNT reinforcement particles enable an effective tribological mechanism for the composite coating.