Tribological Behavior Of PTFE Composites On Textured Dual Surfaces

PTFE is widely used in mechanical seals and aerospace applications due to a range of excellent properties such as heat and cold resistance,corrosion resistance and self-lubrication.As these fields continue to develop,the requirements for PTFE wear resistance and sealing properties are increasing.Therefore,it is important to improve the tribological properties of PTFE.To address the shortcomings of PTFE’s poor wear resistance,this paper takes nano-Si O₂ and GO-modified PTFE composites/304 stainless steel as the research object,and improves the friction and wear behavior of PTFE composites by modifying the filling of PTFE and designing the frictional surface texture of the counterpart in a rational manner.The effect of nano-Si O₂,GO and their compound filling on the tribological properties of PTFE and the effect of the surface roughness of the counterpart on the tribological wear properties of the composites were investigated using the LSM-2R reciprocating tribological wear tester.On this basis,a study was carried out to investigate the effect of micro texture on the surface of the counterpart on the tribological properties of nano-Si O₂ and GO synergistically modified PTFE composites under starved oil lubrication.The transfer film,abrasive chip and wear surface morphology and their elemental distribution were characterised using optical microscopy,scanning electron microscopy,three-dimensional surface profilometer and energy spectrometer analysis.The tribological wear mechanisms of nano-filler modified PTFE composites and surface weaving of PTFE composites were investigated in depth at the microscopic level.The main conclusions of the full paper are as follows:（1）There is a synergistic effect when GO and nano-Si O₂ are compounded and filled,which effectively improves the friction and wear properties of the composite compared with pure PTFE,and the volumetric wear rate of PTFE composite is reduced by 60.36%compared with pure PTFE,which is mainly related to the high-quality transfer film formed during friction.The increase in surface roughness accelerates the composite from the running-in period to the steady-state period,and it is easy to trap abrasive chips,which improves lubrication performance but increases wear.（2）The friction and wear behaviors of PTFE composites were improved by the five different textured duals under starved lubrication.Among them,the elliptic textured dual surface shows the best tribological performance,and the friction coefficient and wear rate of the non-textured surface are reduced by 35.71%and56.47%.The friction coefficient has different characteristics in different periods of friction and wear.It can be divided into three stages,which are defined as steady state,changing state and dry friction stage.（3）Under starved lubrication,there is an optimal combination of dual surface texture parameters,which can further improve the tribological behavior of PTFE composites.Compared with the untextured sample,the elliptical texture sample with an axial ratio of 3,an area ratio of 20%and a depth of 10μm was reduced by 58.33%and the wear resistance increased by 76.78%.In summary,the synergistic effect of nanocomposites and surface texture can effectively improve the tribological properties of the material unde r starved lubrication conditions and increase the service life of the composite.