Preparation Of Fluorinated Graphene/Fluorocarbon Resin Wear-resistant And Anti-corrosion Coating And Its Performance Study

Wear and corrosion were the main culprits of damage to metallic materials and caused considerable losses to national economies every year.Many attempts have been made to enhance the use of metals in microelectronics,construction,motor vehicles,offshore devices and aerospace.The application of organic coatings to metal surfaces was one of the most economical and effective ways of reducing or preventing friction and corrosion of metals.Fluorocarbon resin(FEVE)was often used as a protective coating for substrates due to its large number of C?F bonds,high thermal stability and chemical inertness,which makes it very resistant to wear,corrosion,weathering and staining.It is also used more widely in protective coatings for building facades,aircraft skins,automobiles and heritage.However,pure fluorocarbon resins have poor adhesion to metal substrates and are prone to cracking or peeling in harsh natural environments,leading to corrosion and abrasion,thus compromising the protective and barrier properties of the coating.Therefore,the structure and performance characteristics of the fluorocarbon coating,the selection of suitable filling mean to improve the wear and corrosion resistance of the fluorocarbon coating optimization,so as to obtain a highly effective protective coating,enhance the service life of ship parts,marine facilities and other metals in complex conditions.In this paper,in order to improve the comprehensive performance of fluorocarbon resin coatings in terms of wear and corrosion protection.Using the polymer modification and nanoparticle modification method to investigated the effects of the tribological behavior and corrosion protection properties of fluorocarbon resin composite coatings,including different epoxy resin,fluorinated graphene and nano-zirconium phosphate loaded fluorinated graphene additions.Besides,the wear and corrosion protection mechanisms of the fluorocarbon composite coatings were revealed at the microscopic scale level.The main findings and conclusions of this paper are as follows.(1)The modified fluorocarbon resin coatings were prepared by using an epoxy-fluorocarbon blending method.The tribological behavior of the fluorocarbon resin coatings modified with different contents of epoxy resin was investigated under two friction conditions(dry friction and wet friction(3.5%Na Cl solution)).At the same time,electrochemical impedance spectroscopy(EIS)analysis of the coatings was carried out to study the wear and corrosion resistance performance and mechanism.Compared with FEVE,when the EP addition of 10%,the EP/FEVE coating reduced the wear rate by 69.8%and 66.1%,respectively.Besides,the impedance modulus of the coating was about 3 orders of magnitude higher than that of FEVE after immersion in 3.5%Na Cl solution for 15 days.The mechanism study showed that the EP in the coating was uniformly interspersed in the FEVE,increasing the density of crosslinking points and thus strengthening the wear and corrosion resistance of the FEVE/EP coating.(2)Fluorinated graphene(FG)was successfully prepared by mechanical exfoliation and filled with a fluorocarbon/epoxy blended matrix to produce a fluorinated graphene-fluorocarbon/epoxy(FG-FEVE/EP)nanocomposite coating.The number of fluorinated graphene layers prepared was 4-6,and the exfoliated FG sheets were freely stacked with low orientation and showed good dispersion and interfacial compatibility in the FEVE/EP matrix.Compared to the FEVE/EP coating,the 0.1%FG-FEVE/EP coating reduced the coefficient of friction by 10.6%and 30.7%and the wear rate by 55.1%and 56.1%in dry friction and wet friction(3.5%Na Cl solution)environments,respectively.In addition,EIS testing and fitted data yielded that after 15 days of immersion,the impedance modulus of the 0.1%FG-FEVE/EP coating was two orders of magnitude higher than that of the FEVE/EP coating,and the coating resistance(Rc)value still reached 1.6?10~9?·cm~2,demonstrating excellent corrosion protection performance.The excellent wear and corrosion resistance of the FG-FEVE/EP nanocomposite coating was attributed to the fact that the FG prepared by mechanical peeling was uniformly dispersed and interfacially compatible in the FEVE/EP matrix,which contributed to the excellent interlayer lubrication,stress resistance and barrier corrosion protection of FG.(3)?-Zr P/PDA/FG composites were prepared by assembling zirconium phosphate(?-Zr P)onto the surface of fluorinated graphene(FG)through the bonding action of polydopamine(PDA).It was added to a fluorocarbon resin/epoxy resin(FEVE/EP)coating to investigate the wear and corrosion resistance of the composite coating.The structures of the nanocomposites were characterized using XRD,FT-IR and AFM.The results show that the action of?-Zr P loading on the FG surface leads to a more densely lamellar structure of the FG.In addition,compared with the FEVE/EP matrix,the friction coefficient of the?-Zr P/PDA/FG-FEVE/EP composite coating was reduced by 28%and 30%,and the wear rate was reduced by 63%and56%under two friction conditions,respectively.Meanwhile,EIS test results showed that the impedance modulus of both the?-Zr P/PDA/FG-FEVE/EP composite coating impedance arc and low frequency was 3 orders of magnitude higher than the FEVE/EP coating after 15 days of immersion in a 3.5%Na Cl solution,which makes the application of the modified fluorocarbon coating promising.