Friction heat-driven robust self-lubricity of n-alkanols/epoxy resin coatings enabled by solid-liquid phase transition

Abstract

Due to the inherent damage effect, friction heat is commonly undesirable yet inevitable in moving components, resulting in a great challenge to obtain robust running of the mechanical assemblies under high sliding velocity. Here, we report an alternative strategy to design robust self-healing lubricity materials via taking advantage of friction heat-driven solid-liquid phase transition, by employing facile coatings of n-alkanols/epoxy resin. The lubricity performance of the composite coatings enhances with sliding velocity, leading to the low friction coefficient 0.066 and wear rate 1.968×10-7 mm3/N·m under 5000 rpm. The low friction is mainly attributed to the controlled phase transition characteristics of n-alkanols, which absorb the friction heat to release liquid n-alkanols for maintaining the intelligent shear interfaces. While the low wear is ascribed to the high load-bearing capacity and self-healing property of the composite coatings. This study may thus open the common framework to rationally design self-healing lubricant materials via solid-liquid phase transition by utilizing the undesirable yet inevitable friction heat, for achieving robustly ultralow friction and wear of moving components under harsh working conditions.