MXenes 及其纳米复合涂层在硅 / 聚合物基接触面上的摩擦学行为

To investigate the friction behavior of MXenes and their nano-composite coatings, Ti₃C₂ -MXenes coatings, Ti₃C₂ - MXenes/ nano-diamond composite coatings, and Ti₃C₂ - MXenes/ graphene composite coatings have been prepared on silicon wafer (monocrystalline silicon) substrates. The friction coefficients between the silicon substrate, MXenes, and their nano-composite coatings and ball bearings made of different materials were measured. The surface morphology and composition of the wear spots and abrasion marks were characterized using optical microscopy, three-dimensional white-light interference scanning, and Raman spectroscopy. The results showed that the friction coefficient between the silicon substrate and a polytetrafluoroethylene (PTFE) ball is the lowest after 1 200 rubbing cycles. The silicon substrate surface exhibits clear grooves at the edges of the abrasion marks, indicating that the dominant wear mechanisms are abrasive and adhesive wear. For the polymer ball, the dominant wear mechanisms are abrasive wear and fatigue wear. When the Ti₃C₂ -MXenes coating on the silicon surface is rubbed against the PTFE ball, the self-lubricating action of PTFE stabilizes the friction coefficient of the MXenes coating at 0. 14 under a 1 N load, and there is a noticeable transfer layer of PTFE on the surface of the wear mark. Under a 1 N load, the friction coefficient of the Ti₃C₂ -MXenes/ nano-diamond composite coating rubbed against the PTFE ball remains stable at 0. 15, while under a 0. 5 N load, the friction coefficient of the Ti₃C₂ -MXenes/ graphene composite coating remains stable at 0. 18. Incorporation of graphene results in a reduced transfer layer of the polymer on the silicon surface.