Friction and Wear Characteristics of the GF/BN/EP Composite during Sliding

Abstract

Epoxy resin (EP) was used as the matrix, with glass fiber (GF) and boron nitride (BN) as reinforcements to prepare GF/BN/EP composites for industrial components under complex service conditions. GF/BN/EP composites with BN contents of 0, 0.3, 0.6, 0.9, and 1.2 wt.% were fabricated via vacuum diversion technique, and their tribological behaviors were systematically investigated under dry sliding, oil-lubricated sliding, and argon atmosphere sliding conditions. The results show that the argon atmosphere yields the highest coefficient of friction and wear rate for the composites, due to continuous contact between fresh GF fibers and the steel counterpart, which fails to form an effective adsorbed surface layer. Under all test conditions, the wear rate and friction coefficient of the composites decrease significantly with increasing BN content from 0 to 1.2 wt.%, which is attributed to the excellent solid lubrication and anti-wear properties of BN nanoparticles. In addition, increasing the normal load (40 ~ 120 N) and the sliding speed (2.5 ~ 10 m/s) elevates the tribocontact zone temperature, resulting in thermal softening of the EP matrix and accelerated fiber-matrix debonding, thereby increasing the wear loss of the composites. The worn surface morphology and steel counterpart characterization reveal the wear mechanisms of the composites under different conditions, and the formation of a transfer film on the steel surface in an oil-lubricated environment is the key factor in the lowest tribological loss. This work clarifies the coupling effects of BN content, test parameters, and the sliding medium on the tribological behavior of GF/BN/EP composites. It provides a theoretical basis for the design and industrial application of high-performance polymer-matrix tribological composites.