Study on the effects of different substrates and interlayer slip of graphene coatings on their friction reduction performances
Graphene films,as a two-dimensional material,are excellent lubricants for improving the tribome-chanical properties of micro/nano electro-mechanical systems(MEMS/NEMS).In order to investigate the in-fluence of substrate material and graphene layer number on its friction reduction performance,this paper investi-gates the influence of graphene layer number on the friction reduction effect by preparing graphene coatings with different layer numbers on different substrates and using a combination of atomic force microscopy(AFM)exper-iments and molecular dynamics(MD)simulations.And by establishing the analytical model of the friction per-formance of graphene coatings with different layer numbers,it was investigated that the interlayer slip of graphene is the main factor to produce the wear reduction.The results show that the graphene coating has excellent wear reduction effect on both silicon substrate and copper substrate under different loads,and the friction decreases gradually with the increase of the number of graphene layers,and reaches the optimal 99.3％wear reduction effect when the number of graphene layers is more than 10.The simulation analysis reveals that as the number of layers increases,the dry friction between graphene and substrate transforms into interlayer friction of graphene and generates interlayer shear slip,and the interlayer slip of graphene is the main factor leading to the excellent wear reduction performance of multilayer graphene.
国家科技期刊平台
NSTL
万方数据
维普
