Performance optimization of epoxy resin(EP) modified by phenolic and effect on the tribological properties and corrosion ofMoS₂ + Sb₂O₃/EPcomposite coating for ultra‐long wear life and good corrosion resistance

Abstract

Resin as a continuous and base phase plays a key role in the organic bonded solid lubricating (OBSL) coating. However, the influence mechanism of resin mechanical properties on tribological properties and corrosion resistance of coatings remains elusive. Here, the effect of crosslink density of epoxy resin modified by phenolic resin (Abbr. EP/PH) on the tribological performance /corrosion protection of MoS2 + Sb2O3/EP composite coating has been elucidated. The tribology and corrosion properties of the coatings with different crosslink densities were analyzed by SEM/EDS, XRD, XPS, and EIS. The result indicates that when the crosslink density of resin in the coating is moderate of 460 mol/m3 and the elastic modulus reaches the highest value of 2217 MPa, the MoS2 + Sb2O3/EP composite coating shows low friction coefficient about 0.01, long anti‐wear life (≥480 min), and good corrosion resistance with the higher value of |Z|0.01Hz (1.92 × 1010 Ω cm2) after 72 h of immersion than other coatings. In addition, the too high or too low crosslink density of EP/PH resin is not beneficial to improve the performance of coating. It is because the mechanical strength and toughness of resin with appropriate crosslink density are enhanced greatly, which ensures a tight bond between the filler as a dispersed phase and resin as a continuous phase to form the compact micro‐structure of coating, which improve the strength and shielding capacity of coating, so the MoS2 + Sb2O3/EP composite coating shows good tribological properties and anti‐corrosion.Highlights The effect of resin crosslink density on property of coating has been studied. The strength of resin with suitable crosslink density are enhanced greatly. The coating shows good tribological properties and shielding capacity. The crosslink structure of resin has a great influence on coating properties.