Assessing the Tribological Behavior of Nanoclay-Reinforced Epoxy Coatings Under Dry Sliding and Seawater Lubricated Conditions

The effect of different concentrations 0.5, 1.0, and 1.5 wt.% of nanoclay on the tribological and mechanical properties of epoxy composite coatings under dry sliding and seawater conditions was investigated in this study. The structural features of the prepared nanocomposites were investigated by using FTIR and XRD analysis. Further, the tribometer and surface profilometer was used to investigate the friction coefficient (COF) and wear resistance properties of the composite coatings. The result demonstrates that the COF increases as the concentration of the nanoclay increases under dry sliding conditions, while under seawater conditions, the COF value decreased, and this is attributed to the lubrication provided by the synergistic effect of the seawater and the nanoclay-reinforced coatings. Similarly, the prepared reinforced composite coatings witnessed an increase in hardness of about 25% by the introduction of 1.5 wt.% of nanoclay when compared with the pristine epoxy coatings. The lowest COF and optimum wear resistance were achieved at 0.5 and 1 wt.% nanoclay loading in dry sliding and lubricated conditions. However, at higher loading, coating properties deteriorate sequel to agglomeration. The result demonstrated that the reinforcement of epoxy composite coatings with optimum nanoclay exhibited better tribological and mechanical properties under seawater conditions.