Molecular dynamic simulation study of tribological mechanism of PI composites reinforced by CNTs with different orientations

The tribological models of polyimide (PI) reinforced by carbon nanotubes (CNTs) with different orientations were constructed via a molecular dynamic simulation. The variation of PI molecular chains and frictional interface properties were explored for understanding microscopic tribological mechanism of different oriented CNTs. The average friction coefficients of PI composites reinforced by X-, Y-, and Z-oriented CNTs were 0.242, 0.270, and 0.243. Meanwhile, the abrasion rates of XCNT, YCNT, and ZCNT were 11.5% 34.8%, and 28.0%, respectively. The atomic concentration, interfacial temperature and shear strength of XCNT and ZCNT were higher than those of YCNT. The radial distribution function was simulated and interpreted during the friction process to determine the inherent interaction between PI molecular chains and CNTs with specific orientations.