Effect of Aluminum Alloy Surface Modification on Adhesion of the Modified Polyurethane Coating and Its Corrosion Protective Performance

doi:10.13208/j.electrochem.210127

Abstract

Abstract:

The ordinary organic coatings on aluminum alloy usually encounter a problem of low adhesion to the substrate, which results in destruction and failure of the long-term protective performance of the anticorrosion systems. The surface modification of aluminum alloy is able to enhance the adhesion of organic coating on aluminum alloys, and to improve their protective performance. In this work, a combined surface modification of anodic oxidation and mussel adhesion protein/CeO₂/3-aminopropyltriethoxysilane composite film (MCA) was developed on the aluminum alloy. The adhesion of modified polyurethane coated on the treated aluminum alloy and its corrosion protective performance were evaluated comprehensively by using contact angle, adhesion strength, electrochemical impedance spectroscopy (EIS), and scanning reference electrode technique (SRET). The measurements of EIS and SRET demonstrated that the MCA composite film on anodic oxidized Al possessed self-healing function and provided effective protection against early corrosion of aluminum alloy. The pull-off test showed that both anodic oxidation treatment and MCA composite film modification were able to increase the adhesion of modified polyurethane coating on aluminum alloy, and their combined action were supposed to remarkably enhance the adhesion strength up to 17.1 MPa. The reason for the improvement of adhesion was that the anodic oxidation treatment and MCA composite film modification could improve the surface roughness of aluminum alloy, and enhance the surface wettability and surface polarity, which is beneficent to enhance the bonding of the modified polyurethane coating to aluminum alloy surface. The EIS results showed that no any corrosion occurred for the modified polyurethane coating on the treated aluminum alloy during 65 d immersion in 3.5wt.% NaCl solution. The impedance value in low frequency range of the modified polyurethane coating always maintained at a high order of magnitude on the aluminum alloy treated by anodic oxidation and MCA composite film modification, showing an excellent protective performance of the coating system. The evaluation of Neutral Salt Spray (NSS) indicated that the modified polyurethane coating on the treated aluminum alloy owned superior corrosion protection performance, and the adhesion strength remained 13.1 MPa and no any corrosion was found at the scratch locations even after 1200 h of salt spray testing. It was concluded that combination of anodic oxidation and MCA composite film were capable of significantly improving the adhesion of modified polyurethane coating on aluminum alloy and providing long-term effective corrosion protection for aluminum alloy.

Key words: anodic oxidation, aluminum alloy, modified polyurethane, surface modification, corrosion protection, adhesion

Xian-Yin Kuang, Shao-Qiang Jin, Yan-Hui Cao, Yan-Mei Zhang, Shi-Gang Dong, Long-Hui Zhu, Li-Wen Lin, Chang-Jian Lin. Effect of Aluminum Alloy Surface Modification on Adhesion of the Modified Polyurethane Coating and Its Corrosion Protective Performance[J]. Journal of Electrochemistry, 2021, 27(6): 624-636.

Figures/Tables 11

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References 38

[1]	Williams J C, Starke E A. Progress in structural materials for aerospace systems[J]. Acta. Mater., 2003, 51(19): 5775-5799. doi: 10.1016/j.actamat.2003.08.023 URL
[2]	Dursun T, Soutis C. Recent developments in advanced aircraft aluminium alloys[J]. Mater. Design, 2014, 56: 862-871. doi: 10.1016/j.matdes.2013.12.002 URL
[3]	Zhang B(张波), Fang Z G(方志刚), Li X Y(李向阳), Dong C C(董彩常). Status and prospect of corrosion protection technology about aluminium alloy ship[J]. Mat. China(中国材料进展), 2014, 33(7): 414-417.
[4]	Zhou D(周冬), Li G M(李国明), Chi J H(迟均瀚), Chen S(陈珊). Research status of pulse cathodic protection and its application prospects in aluminum alloy protection[J]. Equip. Environ. Eng.(装备环境工程), 2020, 17(6): 81-85.
[5]	Chen Y L(陈跃良), Wu S J(吴省均), Zhang Y(张勇), Bian G X(卞贵学), Zhang Z Z(张柱柱), Zhang Y G(张杨广). Corrosion behavior and DFR degradation law of 2024-T3 aluminium alloy in different surface state[J]. Equip. Environ. Eng.(装备环境工程), 2020, 17(6): 44-50.
[6]	Denissen P J, Shkirskiy V, Volovitch P, Garcia, S. J. Corrosion inhibition at scribed locations in coated AA2024-T3 by cerium- and DMTD-loaded natural silica microparticles under continuous immersion and wet/dry cyclic exposure[J]. ACS Appl. Mater. Interfaces, 2020, 12(20): 23417-23431. doi: 10.1021/acsami.0c03368 URL
[7]	Mohammadi I, Shahrabi T, Mahdavian M, Izadi M. Sodium diethyldithiocarbamate as a novel corrosion inhibitor to mitigate corrosion of 2024-T3 aluminum alloy in 3.5wt% NaCl solution[J]. J. Mol. Liq., 2020, 307(1): 112965. doi: 10.1016/j.molliq.2020.112965 URL
[8]	Niknahad M, Moradian S, Mirabedini S M. The adhesion properties and corrosion performance of differently pretreated epoxy coatings on an aluminium alloy[J]. Corros. Sci., 2010, 52(6): 1948-1957. doi: 10.1016/j.corsci.2010.02.014 URL
[9]	Chen M A, Xie X, Zhang X M. Interactions of BTESPT silane and maleic anhydride grafted polypropylene with epoxy and application to improve adhesive durability between epoxy and aluminium sheet[J]. Prog. Org. Coat., 2009, 66(1): 40-51. doi: 10.1016/j.porgcoat.2009.05.003 URL
[10]	Dalmoro V, Aleman C, Ferreira C A, Dos Santos J H Z, Azambuja D S, Armelin E. The influence of organophosphonic acid and conducting polymer on the adhesion and protection of epoxy coating on aluminium alloy[J]. Prog. Org. Coat., 2015, 88: 181-190.
[11]	Tang M, Li W, Liu H, Zhu L Q. Influence of K₂TiF₆ in electrolyte on characteristics of the microarc oxidation coating on aluminum alloy[J]. Curr. Appl. Phys., 2012, 12(5): 1259-1265. doi: 10.1016/j.cap.2012.03.003 URL
[12]	Akbari E, Di Franco F, Ceraolo P, Raeissi K, Santamaria M, Hakimizad A. Electrochemically-induced TiO₂ incorporation for enhancing corrosion and tribocorrosion resistance of PEO coating on 7075 Al alloy[J]. Corros. Sci., 2018, 143: 314-328. doi: 10.1016/j.corsci.2018.08.037 URL
[13]	Dickie R A. Paint adhesion, corrosion protection, and interfacial chemistry[J]. Prog. Org. Coat., 1994, 25(1): 3-22. doi: 10.1016/0300-9440(94)00500-1 URL
[14]	Zhu W, Li W F, Mu S L, Yang Y Y, Zuo X. The adhesion performance of epoxy coating on AA6063 treated in Ti/Zr/V based solution[J]. Appl. Surf. Sci., 2016, 384: 333-340. doi: 10.1016/j.apsusc.2016.05.083 URL
[15]	Zhu W, Li W F, Wang K, Mu S L, Fu N Q, Liao Z M, Tian J. Effect of TZVCC drying temperature on the adhesion performance of the epoxy coating on AA6063[J]. J. Adhesion, 2020, 96(6): 565-579. doi: 10.1080/00218464.2018.1483825 URL
[16]	Zhu W, Li W F, Mu S L, Fu N Q, Liao Z M. Comparative study on Ti/Zr/V and chromate conversion treated aluminum alloys: Anti-corrosion performance and epoxy coating adhesion properties[J]. Appl. Surf. Sci., 2017, 405: 157-168. doi: 10.1016/j.apsusc.2017.02.046 URL
[17]	Liu Q, Cao X M, Du A, Ma R N, Zhang X R, Shi T T, Fan Y Z, Zhao X. Investigation on adhesion strength and corrosion resistance of Ti-Zr aminotrimethylene phosphonic acid composite conversion coating on 7A52 aluminum alloy[J]. Appl. Surf. Sci., 2018, 458: 350-359. doi: 10.1016/j.apsusc.2018.07.044 URL
[18]	Song J, Van Ooij W J. Bonding and corrosion protection mechanisms of gamma-APS and BTSE silane films on aluminum substrates[J]. J. Adhes. Sci. Technol., 2003, 17(16): 2191-2221. doi: 10.1163/156856103772150788 URL
[19]	Bajat J B, Milosev I, Jovanovic Z, Jancic-Heinemann R M, Dimitrijevic M, Miskovic-Stankovic V B. Corrosion protection of aluminium pretreated by vinyltriethoxysilane in sodium chloride solution[J]. Corros. Sci., 2010, 52(3): 1060-1069. doi: 10.1016/j.corsci.2009.11.035 URL
[20]	Bajat J B, Miskovic-Stankovic V B, Kacarevic-Popovic Z. Corrosion stability of epoxy coatings on aluminum pretreated by vinyltriethoxysilane[J]. Corros. Sci., 2008, 50(7): 2078-2084. doi: 10.1016/j.corsci.2008.04.018 URL
[21]	Mohseni M, Mirabedini M, Hashemi M, Thompson G E. Adhesion performance of an epoxy clear coat on aluminum alloy in the presence of vinyl and amino-silane primers[J]. Prog. Org. Coat., 2006, 57(4): 307-313. doi: 10.1016/j.porgcoat.2006.09.007 URL
[22]	Tran N T, Flanagan D P, Orlicki J A, Lenhart J L, Proctor K L, Knorr D B. Polydopamine and polydopamine-silane hybrid surface treatments in structural adhesive applications[J]. Langmuir, 2018, 34(4): 1274-1286. doi: 10.1021/acs.langmuir.7b03178 URL
[23]	Zand B N, Mahdavian M. Corrosion and adhesion study of polyurethane coating on silane pretreated aluminum[J]. Surf. Coat. Tech., 2009, 203(12): 1677-1681. doi: 10.1016/j.surfcoat.2008.12.027 URL
[24]	Yuan X, Yue Z F, Chen X, Wen S F, Li L, Feng T. The protective and adhesion properties of silicone-epoxy hybrid coatings on 2024 Al-alloy with a silane film as pretreatment[J]. Corros. Sci., 2016, 104: 84-97. doi: 10.1016/j.corsci.2015.11.035 URL
[25]	Peng N, Wen Y Q, He Y D. Improved distribution of etched tunnels on aluminum foil with silane treatment[J]. Prog. Org. Coat., 2019, 127: 151-156.
[26]	Pan L, Zhang A A, Zheng Z M, Duan L X, Zhang L, Shi Y, Tao J. Enhancing interfacial strength between AA5083 and cryogenic adhesive via anodic oxidation and silaniza-tion[J]. Int. J. Adhes. Adhes, 2018, 84: 317-324. doi: 10.1016/j.ijadhadh.2018.04.006 URL
[27]	Abel M L, Watts J F, Digby R P. The adsorption of alkoxysilanes on oxidised aluminium substrates[J]. Int. J. Adhes. Adhes., 1998, 18(3): 179-192. doi: 10.1016/S0143-7496(97)00059-6 URL
[28]	Zhang F, Pan J, Claesson P M. Electrochemical and AFM studies of mussel adhesive protein (Mefp-1) as corrosion inhibitor for carbon steel[J]. Electrochim. Acta, 2011, 56(3): 1636-1645. doi: 10.1016/j.electacta.2010.10.033 URL
[29]	Sababi M, Zhang F, Krivosheeva O, Forslund M, Pan J S, Claesson P M, Dedinaite A. Thin composite films of mussel adhesive proteins and ceria nanoparticles on carbon steel for corrosion protection[J]. J. Electrochem. Soc., 2012, 159(8): C364-C371. doi: 10.1149/2.061208jes URL
[30]	Jiang P L, Hou R Q, Chen C D, Sun L, Dong S G, Pan J S, Lin C J. Controllable degradation of medical magnesium by electrodeposited composite films of mussel adhesive protein (Mefp-1) and chitosan[J]. J. Colloid. Interf. Sci., 2016, 478: 246-255. doi: 10.1016/j.jcis.2016.06.001 URL
[31]	Gao J H(高镜涵), Li F H(李菲晖), Gong Y L(巩运兰), Ren S(任时). Recent research progress of surface treatments and anodic oxidation of aluminum alloys[J]. Plating and Finishing(电镀与精饰), 2018, 40(8): 18-23.
[32]	Jothi V, Adesina A Y, Kumar A M, Al-Aqeeli N, Ram J S N. Influence of an anodized layer on the adhesion and surface protective performance of organic coatings on AA2024 aerospace Al alloy[J]. Prog. Org. Coat., 2020, 138: 105396.
[33]	Zhang F, Pan J S, Claesson P M, Brinck T. Electrochemical, atomic force microscopy and infrared reflection absorption spectroscopy studies of pre-formed mussel adhesive protein films on carbon steel for corrosion protection[J]. Thin Solid Films, 2012. 520(24): 7136-7143. doi: 10.1016/j.tsf.2012.07.115 URL
[34]	Khun N W, Frankel G S, Zimmerman J. Investigation of surface morphology, wear resistance, and adhesiveness of AA6061-T6 treated in a hexafluorozirconic acid-based solution[J]. Corrosion, 2013, 69(3): 259-267. doi: 10.5006/0798 URL
[35]	Hu J M, Liu L, Zhang J Q, Cao C N. Effects of electrodeposition potential on the corrosion properties of bis-1,2- triethoxysilyl ethane films on aluminum alloy[J]. Electro-chim. Acta, 2006, 51(19): 3944-3949. doi: 10.1016/j.electacta.2005.11.008 URL
[36]	Hu J M, Liu L, Zhang J Q, Cao C N. Electrodeposition of silane films on aluminum alloys for corrosion protection[J]. Prog. Org. Coat., 2007, 58(4): 265-271. doi: 10.1016/j.porgcoat.2006.11.008 URL
[37]	Hu J M, Liu L, Zhang J Q, Cao C N. Preparation of DTMS films on LY12 aluminum alloys via electrochemical deposition and their anti-corrosive performance[J]. Chem. J. Chinese. U., 2006, 27(6): 1121-1125.
[38]	Zhang J Q(张鉴清), Cao C N(曹楚南). Study and evaluation on organic coatings by electrochemical impedance spectroscopy[J]. Corros. Prot.(腐蚀与防护), 1998, 3: 99-104.