Abstract
The surface activity of hot-dip galvanized steel was evaluated after alkaline cleaning by exposing the cleaned specimens in humid supercritical carbon dioxide, followed by extraction and quantification of the formed corrosion products. Different free alkalinities of the cleaning bath were studied to obtain information on the evolution of zinc surface activity at different levels of surface etching. Surface reactivity of uncleaned galvanized steel is restricted and local, with major contributions from grain boundaries and intermetallic particles. Formation of zinc corrosion products took place in uncleaned samples exclusively on and around these sites. Al2O3 removal by alkaline cleaning gradually increased the surface activity. The major increase in surface activity was achieved when increasing the free alkalinity from 0.5 to 4.0 mEq/L, which was shown by formation of zinc corrosion products within zinc grains. The surface activity was confirmed by applying a titanium hexafluoride pretreatment on the cleaned panels and measuring the lateral microscale uniformity of the formed layer. The uniformity increased when larger areas of galvanized steel became activated by alkaline cleaning. Reactivity of zinc is rather difficult to quantify when setting up an industrial cleaning sequence for galvanized steel. Controlled exposure of cleaned samples in humid supercritical carbon dioxide, followed by quantification of oxidized zinc, provides a straightforward method to evaluate zinc reactivity.
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs11998-019-00272-9/MediaObjects/11998_2019_272_Fig1_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs11998-019-00272-9/MediaObjects/11998_2019_272_Fig2_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs11998-019-00272-9/MediaObjects/11998_2019_272_Fig3_HTML.jpg)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs11998-019-00272-9/MediaObjects/11998_2019_272_Fig4_HTML.jpg)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs11998-019-00272-9/MediaObjects/11998_2019_272_Fig5_HTML.jpg)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs11998-019-00272-9/MediaObjects/11998_2019_272_Fig6_HTML.png)
![](http://media.springernature.com/m312/springer-static/image/art%3A10.1007%2Fs11998-019-00272-9/MediaObjects/11998_2019_272_Fig7_HTML.jpg)
Similar content being viewed by others
References
Markets for prepainted metal, http://prepaintedmetal.eu/874/947
Ohlsson, K, Bergman, T, Sundell, P-E, Deltin, T, Tran, I, Svensson, M, Johansson, M, “Novel Coil Coating Systems Using Fatty Acid Based Reactive Diluents.” Prog. Org. Coat., 73 (4) 291–293 (2012)
Gao, Z, Zhang, D, Liu, Z, Li, X, Jiang, S, Zhang, Q, “Formation Mechanisms of Environmentally Acceptable Chemical Conversion Coatings for Zinc: A Review.” J. Coat. Technol. Res.,16 (1) (2019)
Sinko, J, “Challenges of Chromate Inhibitor Pigments Replacement in Organic Coatings.” Prog. Org. Coat., 42 267–282 (2001)
Belov, I, Copeland, D, Fitzwater, B, Knapps, J, Lewis, T, “Developement of Chromium (VI)-Free Coating Systems for Corrosion and Heat Protection.” In: Proc. Coatings Science International, pp 41–45 (2015)
Visser, P, Liu, Y, Terryn, H, Mol, JMC, “Lithium Salts as Leachable Corrosion Inhibitors and Potential Replacement for Hexavalent Chromium in Organic Coatings for the Protection of Aluminum Alloys.” J. Coat. Technol. Res., 13 (4) 557–566 (2016)
Montemor, MF, “Functional and Smart Coatings for Corrosion Protection: A Review of Recent Advances.” Surf. Coat. Technol., 258 17–37 (2014)
Kaluzny, K, “Why Some Metals and Alloys Are More Difficult to Pretreat than Others - Part I.” Met. Finish., 100 (9) 9–19 (2002)
Hörnström, SE, Hedlund, EG, Klang, H, Nilsson, J-O, Backlund, M, Tegehall, P-E, “A Surface Study of the Chemical Pretreatment before Coil Coating of Hot Dip Zinc-Coated Steel.” Surf. Interface Anal., 19 (1–12) 121–126 (1992)
Azmat, NS, Ralston, KD, Cole, IS, “Pre-Treatment of Zn Surfaces for Droplet Corrosion Studies.” Surf. Coat. Technol., 205 (3) 928–935 (2010)
Berger, R, Bexell, U, Stavlid, N, Grehk, TM, “The Influence of Alkali-Degreasing on the Chemical Composition of Hot-Dip Galvanized Steel Surfaces.” Surface and Interface Analysis, 1130–1138 (2006)
Maeda, S, “Surface Chemistry of Galvanized Steel Sheets Relevant to Adhesion Performance.” Prog. Org. Coat., 28 (4) 227–238 (1996)
Schoeman, L, Burty, M, “Cleaning Optimization of Hot-Dip Galvanized Steel Surfaces in Preparation for Paint Application.” Mater. Sci. Forum, 941 1772–1777 (2018)
Falk, T, Svensson, J, Johansson, L, “The Role of Carbon Dioxide in the Atmospheric Corrosion of Zinc.” J. Electrochem. Soc., 145 (1) 39–44 (1998)
Bozbaʇ, SE, Erkey, C, “Supercritical Deposition: Current Status and Perspectives for the Preparation of Supported Metal Nanostructures.” J. Supercrit. Fluids, 96 298–312 (2015)
Snoeyink, V, Jenkins, D, Water Chemistry. Wiley, New York (1980)
Kaleva, A, Saarimaa, V, Heinonen, S, Nikkanen, J.-P, Markkula, A, Väisänen, P, Levänen, E, “Dissolution-Induced Nanowire Synthesis on Hot-Dip Galvanized Surface in Supercritical Carbon Dioxide.” Nanomaterials, 7 (7) (2017)
Saarimaa, V, Kaleva, A, Paunikallio, T, Nikkanen, J-P, Heinonen, S, Levänen, E, Väisänen, P, Markkula, A, “Convenient Extraction Method for Quantification of Thin Zinc Patina Layers.” Surf. Interface Anal., 50 (5) 564–570 (2018)
Leroy, V, “Metallurgical Applications of Surface Analytical Techniques.” Mater. Sci. Eng., 42 (C) 289–307 (1980)
Feliu, S, Jr, Barranco, V, “XPS Study of the Surface Chemistry of Conventional Hot-Dip Galvanised Pure Zn, Galvanneal and Zn-Al Alloy Coatings on Steel.” Acta Mater., 51 5413–5424 (2003)
Wolpers, M, Angeli, J, “Activation of Galvanized Steel Surfaces before Zinc Phosphating - XPS and GDOES Investigation.” Appl. Surf. Sci., 179 281–291 (2001)
Biber, HE, “Scanning Auger Microprobe Study of Hot-Dipped Regular-Spangle Galvanized Steel: Part I. Surface Composition of as-Produced Steel.” Metall. Trans. A, 19A 1603–1608 (1988)
Marder, AR, “The Metallurgy of Zinc-Coated Steel.” Prog. Mater. Sci., 45 (3) 191–271 (2000)
Strutzenberger, J, Faderl, J, “Solidification and Spangle Formation of Hot-Dip-Galvanized Zinc Coatings.” Met. Mater. Trans. A, 29A 631–645 (1998)
Peng, D, Wu, J, Yan, X, Du, X, Yan, Y, Li, X, “The Formation and Corrosion Behavior of a Zirconium-Based Conversion Coating on the Aluminum Alloy AA6061.” J. Coat. Technol. Res., 13 (5) 837–850 (2016)
Rangel, CM, Paiva, TI, Luz, PP, “Conversion Coating Growth on 2024-T3 Al Alloy The Effect of Pre-Treatments.” Surf. Coat. Technol., 202 3396–3402 (2008)
Lunder, O, Simensen, C, Yu, Y, Nisancioglu, K, “Formation and Characterisation of Ti-Zr Based Conversion Layers on AA6060 Aluminium.” Surf. Coat. Technol., 184 (2–3) 278–290 (2004)
Nordlien, JH, Walmsley, JC, Østerberg, H, Nisancioglu, K, “Formation of a Zirconium-Titanium Based Conversion Layer on AA 6060 Aluminium.” Surf. Coat. Technol., 153 (1) 72–78 (2002)
Saarimaa, V, Markkula, A, Juhanoja, J, Skrifvars, BJ, “Improvement of Barrier Properties of Cr-Free Pretreatments for Coil-Coated Products.” J. Coat. Technol. Res., 12 (4) 721–730 (2015)
Ramezanzadeh, B, Attar, MM, Farzam, M, “Corrosion Performance of a Hot-Dip Galvanized Steel Treated by Different Kinds of Conversion Coatings.” Surf. Coat. Technol., 205 (3) 874–884 (2010)
Saarimaa, V, Kauppinen, E, Markkula, A, Juhanoja, J, Skrifvars, B-J, Steen, P, “Microscale Distribution of Ti-Based Conversion Layer on Hot Dip Galvanized Steel.” Surf. Coat. Technol., 206 19–20 (2012)
Saarimaa, V, Kauppinen, E, Markkula, A, Juhanoja, J, Skrifvars, BJ, Steen, P, “Microscale Distribution of Ti-Based Conversion Layer on Hot Dip Galvanized Steel.” Surf. Coat. Technol., 206 (19–20) 4173–4179 (2012)
Verdier, S, van der Laak, N, Dalard, F, Metson, J, Delalande, S, “An Electrochemical and SEM Study of the Mechanism of Formation, Morphology, and Composition of Titanium or Zirconium Fluoride-Based Coatings.” Surf. Coat. Technol., 200 (9) 2955–2964 (2006)
Verdier, S, Van Der Laak, N, Delalande, S, Metson, J, Dalard, F, “The Surface Reactivity of a Magnesium-Aluminium Alloy in Acidic Fluoride Solutions Studied by Electrochemical Techniques and XPS.” Appl. Surf. Sci., 235 (4) 513–524 (2004)
Lostak, T, Maljusch, A, Klink, B, Krebs, S, Kimpel, M, Flock, J, Schulz, S, Schuhmann, W, “Zr-Based Conversion Layer on Zn-Al-Mg Alloy Coated Steel Sheets: Insights into the Formation Mechanism.” Electrochim. Acta, 137 65–74 (2014)
Deck, P, Moon, M, Sujdak, R, “Investigation of Fluoacid Based Conversion Coatings on Aluminium.” Prog. Org. Coat., 34 39–48 (1998)
Saarimaa, V, Markkula, A, Arstila, K, Manni, J, Juhanoja, J, “Effect of Hot Dip Galvanized Steel Surface Chemistry and Morphology on Titanium Hexafluoride Pretreatment.” Adv. Mater. Phys. Chem., 7 28–41 (2017)
Saarimaa, V, Markkula, A, Juhanoja, J, Skrifvars, B-J, “Novel Insight to Aluminum Compounds in the Outermost Layers of Hot Dip Galvanized Steel and How They Affect the Reactivity of the Zinc Surface.” Surf. Coat. Technol., 306 (2016)
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Saarimaa, V., Lange, C., Paunikallio, T. et al. Evaluation of surface activity of hot-dip galvanized steel after alkaline cleaning. J Coat Technol Res 17, 285–292 (2020). https://doi.org/10.1007/s11998-019-00272-9
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11998-019-00272-9