| This paper studied by using potassium titanate whiskers(PTW) and polytetrafluoroethylene(PTFE) filled with modified polyether ether ketone(PEEK), obtained PTW/PEEK and PTFE/PTW/PEEK composites, studied the mechanical properties and Tribological Properties of the composite materials.First with the coupling agent on PTW activation treatment, screening to determine the appropriate type of coupling agent and the best quantity, by activated PTW filled with modified PEEK composites, injection molding test specimens. Using MM200 friction and wear testing machine and 45# steel ring with side studied effects of PTW concentration on the tribological properties of the composite materials and PTW and PTFE on the synergistic effect of composite materials, using scanning electron microscopy analyzed the fracture surface of composite and the wear surface morphology, and analyzed the wear mechanism.The results of the study showed that, titanate coupling agent TM38-S was suitable for activation treatment of PTW, and when TM38-S dosage was 1%, the best activation effected. Injection molding of PTW/PEEK composite studies had shown that injection temperature and mold temperature was extremely important for the mechanical properties of the composites: as injection temperature increasing, the tensile strength and bending strength of products presented at first and then decreased, when the molding temperature was too high, the phenomenon of increased thermal decomposition of PEEK, easily to generate large spherulites in injection molding products, so that the product was fragile, and mechanical properties decreased; as molding temperature increasing, the tensile strength and bending strength of products also increased, but when the mold temperature was too high, product internal gas holed, easily to produce the products collapse phenomenon. So the mold temperature control for(180±10) ℃, at this temperature, the melt filling characteristics of good material, high degree of crystallinity, and no crystallization peak, excellent mechanical performance; Moreover through annealing treatment on mechanical properties of PTW/PEEK products, PTW/PEEK products had further improved. In the injection molding temperature in sequence from front to back was 390℃, 380℃, 365℃, the mold temperature was 180℃, injection molding of PTW/PEEK product, and on the annealing conditions of 200℃, then 1H annealing was performed on the specimen, we could get composite of best comprehensive performance through this method.Under dry friction condition, the filling of PTW could significantly reduce the friction coefficient of PEEK composites, with the increase of PTW content, friction coefficient of PTW/PEEK composite decreased first and then increased slightly, the wear loss of composites also decreased with the increasing of PTW contents, when the content of PTW was 15% the wear resistance of composite was best. PTFE in a certain mass ratio of added to the PTW/PEEK composite materials could reduce the friction coefficient of the composite, also made the wear resistance of the composites increased significantly, and as the mass fraction of PTFE increased, the wear resistance of PTFE/PTW/PEEK composites increased, but the mechanical properties of the composites decreased, which was due to poor compatibility between different components. The analysis considered, PTW whisker enhanced the bearing capacity of composite material surface, reducing friction surface adhesion and delamination in the friction process, the plastic deformation of the matrix resin and prevent heat, PTFE preferred adhesive transfer made the PTW/PTFE/PEEK composite formed on the surface of the dual transfer film of the thin, continuity and uniformity of the two best, collaborative effectively improved the tribological properties of composite materials. Considering the composite wear-resistant properties, mechanical properties and cost of the formula, this paper studies the optimum ratio of PTW: PTFE: PEEK composite material for 15:8:77. |
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