Evaluation of high temperature tribological behavior of electroless deposited NiB–Al2O3 coating

Abstract This paper investigates the tribological behavior of the electroless NiB and NiB–Al2O3 coatings on mild steel (St-37) substrates. The temperature-dependent wear setup was used to evaluate the high temperature tribological behavior of the coatings. The effects of Al2O3 concentration, wear testing configuration, and testing temperature on the predominant wear mechanism of the coatings were discussed in detail. The tribological tests were performed at 25 °C, 200 °C, 400 °C and 600 °C using a ball-on-disk setup to investigate how the temperature affects the tribological behaviors of the coatings under the constant applied load of 3 N. The experimental results showed that, NiB–Al2O3 coating exhibited lower wear rate at all operated test temperatures and the addition of Al2O3 nanoparticles improved the wear behaviors of the coatings. The tribological behaviors of the coatings were confirmed using Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDS), and Raman Spectroscopy.