Study On The Properties Of Antifriction And Wear Resistance Of Resin Matrix Composite And Their Finite Element Simulations

In recent years,the rapid development of the modified technologies of it were promoted owing to the performance requirements of resin material used in industries trending to be diversified and functional.At present,resin matrix composites have been widely applied in many fields because of their flexible performance adjustment.This text adopts two common thermoplastic resins,polyether ether ketone(PEEK)and poly(vinylidene fluoride)(PVDF)as the matrix,with the help of the special material structure and the fillers to enhance the heat transfer and self-lubricating processes,to fabricate antifriction and wear-resistance composites,aim to satisfy some resin antifriction and wear-resistance parts(such as the sliding bearing,seal ring,the slider and so on)requirements in petrochemical field.We systematically investigate the factors that affect the tribological properties of the composites,and the friction and wear mechanism of the composites are discussed.In addition,this paper also revealed the process of antifriction and wear-resistance of the composites by establishing a two-dimensional finite element model in ANSYS software,from the view of temperature field,stress field and displacement field.The main contents are as follows.1.Porous self-lubricating PEEK composites(PSPC)with nano-micro multilevel pore structure(N-MPS)incorporated by ionic liquid were fabricated via moulding-leaching and vacuum suction technologies,where sodium chloride(NaCl)was chosen to be micron pore-forming agent,activated carbon fiber(ACF)and polytetrafluoroethylene(PFTE)acted as self-lubricating fillers.The tribological properties of PSPC with different porosities were investigated by using a tribo-tester under an applied load of 250 N and a sliding speed of 0.69 m s-1.Moreover,a finite element(FE)model with N-MPS was firstly developed to reveal the nano-micron scale collaborative lubrication mechanism of the composites.The temperature field,von Mises stress and displacement fields of the FE model under different porosity conditions were studied in heat-stress coupled field using ANSYS software.The accuracy of the simulation results was verified by comparing them with corresponding experimental results with the error values less than 10%.Both the experiment and simulation results showed that the PSPC exhibited excellent tribological properties when the porosity was16.8%.It reflects that FE method is capable of studying the self-lubricating process of nano-micro multilevel porous composites with an optimized FE model.2.A moulding-segmented sintering process was adopted to prepare a hydrophobic and oleophilic PVDF-based composite with nano-micro multilevel pore structure,whereNH4HCO3 as micron pore-forming agent,nanometer silica(Si O2)and carbon nanotubes(CNTs)as nanometer lubricating materials and fluorinated ethylene propylene copolymer(FEP)as low surface energy material.The results of composite showed excellent hydrophobic and oleophilic properties with a water contact angle(WCA)of 164° and oil contact angle(OCA)about 0°.In addition,we prepared a PVDF-based composite with dual effect of antifriction and wear-resistance and hydrophobic by vacuum suction of perfluorinated polyether(PFPE)into the abundant pore structure within the material.The effect of oil absorption on the tribological properties of PVDF-based composite was studied on a friction and wear tester.The results indicated that the composite showed excellent tribological properties with the oil absorption of 44.1%,and its wear resistance increased by 51 times and1.6 times respectively,compared with pure PVDF and PVDF composite without PFPE lubricant.The effect of normal load on the tribological properties of the composite and the contact angle variation of the worn surfaces were also investigated.Moreover,the nano-micro structure and the positive effect of lubricant displacement on the properties of antifriction and wear-resistance of the composites were studied through SEM results and finite element simulation method.3.Two PVDF-based composites filled with microcapsules(MC)which possess the property of self-lubricating were prepared by moulding-sintering method.The effect of MC content on the tribological properties of the composite and the stability of friction coefficient of three tribo-materials were investigated.The results indicated that the MC/PVDF composite showed a stable friction coefficient during the friction process and the wear resistance of it were 120 times and 2.6 times comparing with pure PVDF and MC/CF/PVDF composites,respectively.The results of SEM showed that a lubricating film was formed between the friction pairs after the bursting of microcapsules during the friction process.Moreover,the wear debris could continually fill the broken microcapsule and further decreased the abrasive wear of the composite.Thus,the PVDF-based composites showed excellent properties of antifriction and wear-resistance.