Abstract：The 45 steel was sealing treated for various time in 6%(volume fraction)KH560 solution after the hot-dip aluminizing-anode oxidation. An Al-Al2O3-silane composite coating was formed on the surface of the 45 steel. The microstructure of composite coating was studied. The corrosion resistance of composite coating and its effect on the galvanic corrosion between the 45 steel and 30%(mass fraction)Cf/nylon6 composite were investigated. The results show that the silane coating effectively seals the cracks in Al2O3 coating, prevents the corrosive liquid from attacking the substrate. Hence, the corrosion resistance of the 45 steel is improved. Meanwhile, the good insulation property of the Al-Al2O3-silane composite coating can reduce the driving force of the galvanic corrosion between the 45 steel and 30%Cf/nylon6 composite, consequently, the galvanic corrosion resistance of 45 steel also is improved. After treated with the optimal KH560 treatment process for 5 min, the self-corrosion current density of the hot-dip aluminized 45 steel decreases by 3 orders of magnitude compared with that of the single hot-dip aluminized sample while the electrochemical impedance increases by 2 orders of magnitude, and the galvanic corrosion current density between the 45 steel and 30%Cf/nylon6 composite decreases by about 75%.
 VIÑOLES-CEBOLLA R,BASTANTE-CECA M J,CAPUZ-RIZO S F.An integrated method to calculate an automobile's emissions throughout its life cycle[J].Energy,2015,83:125-136.
 CRISTINA D S M,MONTES-SANCHO M J,BUSCH T.A natural resource-based view of climate change:innovation challenges in the automobile industry[J].Journal of Cleaner Production,2016,139:1436-1448.
 DELOGU M,ZANCHI L,MALTESE S,et al.Environmental and economic life cycle assessment of a lightweight solution for an automotive component:a comparison between talc-filled and hollow glass microspheres-reinforced polymer composites[J].Journal of Cleaner Production,2016,139:548-560.
 PAN Y C,WU G Q,CHENG X,et al.Galvanic corrosion behaviour of carbon fibre reinforced polymer/magnesium alloys coupling[J].Corrosion Science,2015,98:672-677.
 邓华,高军鹏,包建文.取向非连续碳纤维复合材料制备与性能[J].航空材料学报,2018,38(1):69-74. DENG H,GAO J P,BAO J W.Preparation and mechanical properties of aligned discontinuous carbon fiber composites[J].Journal of Aeronautical Materials,2018,38(1):69-74.
 邓富泉,张丽,刘少祯,等.单向连续碳纤维-玻璃纤维层间混杂增强环氧树脂基复合材料的力学性能[J].复合材料学报,2018,35(7):1857-1863. DENG F Q,ZHANG L,LIU S Z,et al.Mechanical properties of unidirectional carbon fiber-glass fiber hybrid reinforced epoxy composites in interlaminar layer[J].Acta Materiae Compositae Sinica,2018,35(7):1857-1863.
 CHEN J,DING N,LI Z,et al.Organic polymer materials in the space environment[J].Progress in Aerospace Sciences,2016,83:37-56.
 张宝宏,丛文博,杨萍.金属电化学腐蚀与防护[M].北京:化学工业出版社,2005. ZHANG B H,CONG W B,YANG P.Electrochemical corrosion and protection of metals[M].Beijing:Chemical Industry Press,2005.
 CUI T F,LIU D X,SHI P A,et al.Effect of stress and galvanic factors on the corrosion behave of aluminum alloy[J].Journal of Wuhan University of Technology(Materials Science Edition),2018,33(3):688-696.
 ZHANG C,ZHENG D J,SONG G L.Galvanic effect between galvanized steel and carbon fiber reinforced polymers[J].Acta Metallurgica Sinica(English Letters),2017,30(4):342-351.
 LIU W,LI Q,LI M C.Corrosion behaviour of hot-dip Al-Zn-Si and Al-Zn-Si-3Mg coatings in NaCl solution[J].Corrosion Science,2017,121:72-83.
 朱雪梅,张振卫,王新建,等.Fe30Mn5Al合金氧化改性层的电化学腐蚀性能[J].材料工程,2017,45(8):83-87. ZHU X M,ZHANG Z W,WANG X J,et al.Electrochemical corrosion behavior of oxidation layer on Fe30Mn5Al alloy[J].Journal of Materials Engineering,2017,45(8):83-87.
 MA Y L,CHEN X L,ZHOU X R,et al.Microstructural origin of localized corrosion in anodized AA2099-T8 aluminium-lithium alloy[J].Surface and Interface Analysis,2016,48(8):739-744.
 LI J,CUI J C,YANG J Y,et al.Silanized graphene oxide reinforced organofunctional silane composite coatings for corrosion protection[J].Progress in Organic Coatings,2016,99:443-451.
 张新芳,欧孝通,刘雷,等.镁合金表面无机-有机杂化硅膜的制备及其防护性能研究[J].中国腐蚀与防护学报,2017,37(5):43-51. ZHANG X F,OU X T,LIU L,et al.Preparation and protective properties of inorganic-organic hybrid silane-coatings on Mg-alloy AZ31[J].Journal of Chinese Society for Corrosion and Protection,2017,37(5):43-51.
 PAN Y C,WU G Q,HUANG Z,et al.Corrosion behaviour of carbon fibre reinforced polymer/magnesium alloy hybrid laminates[J].Corrosion Science,2016,115:152-158.
 FIGUEIRA R B, CALLONE E, SILVA C J R,et al.Hybrid coatings enriched with tetraethoxysilane for corrosion mitigation of hot-dip galvanized steel in chloride contaminated simulated concrete pore solutions[J].Materials,2017,10(3):306.
 ZHANG W,FANG S J,LI L X.Growing model of interfacial layer between alloy layer and matrix in diffusion process of hot dip aluminized steel[J].Advanced Materials Research,2010,154/155:1203-1208.
 LEI L,SHI J,WANG X,et al.Microstructure and electrochemical behavior of cerium conversion coating modified with silane agent on magnesium substrates[J].Applied Surface Science,2016,376:161-171.