| Polyphenylene sulfide (PPS) is an excellent special engineering plastics, it hasexcellent heat resistance, corrosion resistance, electric properties, flame retardancy, metalbonding strength，self-lubrication effect，and a certain amount of load capacity. Due to thecontinuous development of polymer materials, the higher performance requirements onmaterials，as well as poor toughness and low impact strength of PPS, make the wideapplication of PPS was limited. This is the first time to use two kinds of high-performanceengineering plastic polyether sulfone (PES) and polyphenyl ester (Ekonol) in thisexperiment, as well as solid lubricant graphite (G) and molybdenum disulfide (MoS2) areused to modify PPS, the performance of PPS multiple composite coating was researched.The coating was prepared by liquid phase mixing method,and theG/MoS2/Ekonol/PES/PPS multi-element composite coatings was prepared by dippingmethod.This paper was expounded the technological process of the preparation of thecoating, and analyzed the coatings of the filler components and the crystallinity by XRD.The factors of filler, curing time, curing temperature and coating thickness influence on thecombining strength of coating was was investigated. The friction and wear properties ofPPS composite coating was tested under different conditions,include dry friction, waterlubrication and oil lubrication, as well as the condition of different load and different speed.Finally discussed and analyzed the coating wear mechanism in this paper. The mainconclusions are summarized as follows:(1) G/MoS2/Ekonol/PES/PPS composite coating was prepared by suspension dipcoating method. XRD analysis showed that addition of PPS and PES can reduce thecomposite coating crystallinity, so the addition of Ekonol increases the crystallinity of thecomposite coating.(2) PPS, PES and Ekonol have a great influence on the binding strength of the coating. Using the composite coating formula Ekonol:PES:PPS:G/MoS2: assistant=25:20:45:8:2，itcan be combined with greater strength. The bonding strength of PPS composite coating islower than the pure PPS coating, the bonding strength increased at first and then decreased,but6#and7#PPS composite coating’s adhesion is poor, cannot form an effective coating.(3) Curing time, curing temperature and the thickness of the coating have a significanteffect on bonding strength of and coating substrate. Control of PPS composite coating’scuring temperature at330℃~350℃, curing time at the range from15to25min, thecoating thickness control in the range of100~200um, can obtain the ideal compositecoating.(4) Under different friction conditions, there is a big difference between thecoefficient of friction of different formulation of coating and wear mechanism of thecomposite coating. Under the condition of dry friction, water lubricated and oil lubricated,the friction coefficient is the best under the condition of oil lubrication, the second is in thecondition of water lubrication. Under dry friction condition, PPS composite coatingincreased with increasing Ekonol and PES content, the wear of the composite coatingchanged from abrasive wear, adhesive wear transition to fatigue wear, and when theEkonol content is more than20%, the content of PES is greater than15%, the wear ofcomposite coatings have to plow, abrasive wear transition; under water lubrication, thewear mechanism of composite coating to mainly adhesion wear, when Ekonol content ismore than30%, the content of PES is greater than25%, PPS composite coating changed tofatigue wear and adhesive wear and abrasion mechanism; under the condition of oillubrication, the wear of the composite coating had happened first by the plow Geng,abrasive wear to adhesive wear transition, when the Ekonol content is more than25%, PEScontent is more than20%, composite coating is fatigue wear and adhesive wearcharacteristics.(5) In a different load conditions, the friction coefficient of PPS composite coatingafter the coating is lower than that of pure PPS, decreased by about63%, the frictionresistance is greatly improved. When the load is increased from20N to50N, the friction coefficient decreases with the increase of load, in between50N~200N, the frictioncoefficient with the increase of the load decreases slowly, finally basically unchanged. Atthe same time, with the increase of the load, the wear mechanism of3#PPS compositecoating changed from fatigue wear and adhesion wear to adhesive wear and abrasive wearcharacteristics of change.(6) In a different speed conditions, the friction coefficient of PPS composite coatingafter the coating is lower than that of pure PPS, tribological properties are improved, the2#and4#polyphenylene sulfide composite coating on friction and wear properties of the best.At the same time, with the increase of rotational speed, the wear mechanism of3#PPScomposite coating by fatigue wear to adhesive wear and fatigue wear to abrasive wear andadhesive wear characteristics change occurs. |
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