微弧氧化(Micro arc oxidation)為電化學表面處理技術，適用於鋁、鎂、鈦等輕金屬合金。在微弧氧化的過程中藉由高電壓產生電弧放電，在基材與電解液間電漿電化學反應，氧化金屬基材獲得的膜層具有強附著力、耐摩特性、及較佳抗腐蝕性。然而，微弧氧化膜層表面為多孔結構，腐蝕液仍經由孔洞入侵以腐蝕金屬表面。本實驗藉由醋酸鎳封孔處理與高分子塗覆第二層改善微弧氧化膜層耐腐蝕性，量測處理後的腐蝕特性，證明抗腐蝕性得到改善。
AZ91D鎂合金微弧氧化在矽酸系統電解液環境進行，進一步作醋酸鎳封孔處理與高分子塗覆。高分子塗覆技術分別採用商業化PTFE溶膠與氟碳樹脂(Zeffle)塗覆，再進一步對膜層做一連串的表面及電化學檢測。鎳封孔處理後的微弧氧化膜耐腐蝕性增加有限，唯有經高分子處理後的複式膜，耐腐蝕性方能大幅增加。複式膜的表面疏水性、平整度也大幅增加，尤其是PTFE複式膜。

Micro arc oxidation (MAO) is one of the surface coating technologies, suitable for passivating the lightweight metal surfaces of aluminum, magnesium, and titanium. Various plasma enhanced reactions between substrate and electrolyte by microdischarges are activated under high voltage during micro-arc oxidation. The coating, obtained from the oxidized metal substrate, has unique properties of strong adhesion, wear, and corrosion resistance. However, the surface of the micro-arc oxide coating is also porous, and the etching species, such as chlorine anions, invade through the holes and cracks to corrode the metal underneath. In this experiment, the corrosion resistance of the MAO coating was upgraded by the sealing treatment of nickel acetate. The MAO coatings with and without sealing are further coated with a second layer of PTFE-based polymer. The corrosion resistance of AZ91D surface after the treatment are characterized, attesting the corrosion resistance is improved.
MAO oxidizes the magnesium alloy surface in the electrolytic solution of sodium silicate, and the surface is further passivated with nickel acetate sealing and polymer coating. Two types of polymer have been applied, PTFE sol (Dupont) and fluorocarbon resin (Zeffle). Further, a series of surface and electrochemical analysis of the treated surface have been performed. The micro-arc oxidation coating after nickel sealing renders limited protection. And the polymer coating is shown to improve the corrosion resistance significantly. The surface hydrophobicity and flatness of the composite membrane are also greatly enhanced, especially the PTFE composite membrane.

1. A. Lugovskoy, and M. Zinigr, “Plasma Electrolytic Oxidation of Valve Metals,” 2013.
2. C. Blawert et al., “Anodizing Treatments for Magnesium Alloys and Their Effect on Corrosion Resistance in Various Environments,” Advanced Engineering Materials, vol. 8, no. 6, pp. 511-533, 2006.
3. Y. G. Ko et al., “An electrochemical analysis of AZ91 Mg alloy processed by plasma electrolytic oxidation followed by static annealing,” Journal of Alloys and Compounds, vol. 509, pp. S468-S472, 2011.
4. M. M. Lohrengel, “Thin anodic oxide layers on aluminium and other valve metals: high field regime,” Materials Science and Engineering, vol. Rll, pp. 243-294, 1993.
5. E. V. Parfenov et al., “Towards smart electrolytic plasma technologies: An overview of methodological approaches to process modelling,” Surface and Coatings Technology, vol. 269, pp. 2-22, 2015.
6. F. C. Walsh et al., “Plasma electrolytic oxidation (PEO) for production of anodised coatings on lightweight metal (Al, Mg, Ti) alloys,” Transactions of the IMF, vol. 87, no. 3, pp. 122-135, 2013.
7. Mihael M. Avedesian and Noranda Magnesium Inc., ASM Specialy Handbook, “Magnessium and Magnessium Alloys”, Ohio: ASM International Materials Park, 1999.
8. M.A, H. Baker, ASTM Specialty Handbook, 1999.
9. 陳 輝，陳國寧，利用有機-無機混成法製備金屬防蝕薄膜之研究，碩士論文，化學工程與材料工程研究所，2005。
10. R.O. Hussein, X. Nie, D. O, Northwood, An investigation of ceramic coating growth mechanisms in plasma electrolytic oxidation (PEO) processing, Electrochimica Acta, 112, 2013, 111–119.
11. 薛俊峰，鎂合金防腐蝕技術，化學工業出版，2010。
12. H. Huo, Y. Li, F. Wang, “Corrosion of AZ91D magnesium alloy with a chemical conversion coating and electroless nickel layer.” Corrosion science, 46 1467–1477, 2004
13. Gray, J. and B. Luan, Protective coatings on magnesium and its alloys—a critical review. Journal of alloys and compounds, 2002. 336(1): p. 88-113.
14. A. A. Voevodin et al., “Characterization of wear protective Al-Si-0 coatings forrned on Al-based alloys by micro-arc discharge treatment,” Surface and Coatings Technology, vol. 86-87, pp. 516-521, 1996.
15. W. Xue et al., “Analysis of Phase Distribution for Ceramic Coatings Formed by Microarc Oxidation on Aluminum Alloy,” J. Am. Ceram. Soc., vol. 81, pp. 1365-68, 1998.
16. X. Lu et al., “Insights into plasma electrolytic oxidation treatment with particle addition,” Corrosion Science, vol. 101, pp. 201-207, 2015.
17. L. O. Snizhko et al., “Excessive oxygen evolution during plasma electrolytic oxidation of aluminium,” Thin Solid Films, vol. 516, no. 2-4, pp. 460-464, 2007.
18. F. Jaspard-Mécuson et al., “Tailored aluminium oxide layers by bipolar current adjustment in the Plasma Electrolytic Oxidation (PEO) process,” Surface and Coatings Technology, vol. 201, no. 21, pp. 8677-8682, 2007.
19. 王建貿，微弧氧化鋁合金6061製備綠色顏料膜層，碩士論文，國立台灣科技大學化學工程研究所，pp8-12，2016。
20. 葉尚峻，亞硝酸鈉及尿素在微弧氧化的作用及染色陶瓷膜，碩士論文，國立台灣科技大學化學工程研究所，pp5-6，2015。
21. A. L. Yerokhin et al., “Oxide ceramic coatings on aluminium alloys produced by a pulsed bipolar plasma electrolytic oxidation process,” Surface and Coatings Technology, vol. 199, no. 2-3, pp. 150-157, 2005.
22. A. L. Yerokhin et al., “Characterisation of oxide films produced by plasma electrolytic oxidation of a Ti᎐6Al᎐4V alloy,” Surface and Coatings Technology, vol. 130, pp. 195-206, 2000.
23. 劉宸侑，氧化鉻膠體電解液內微弧氧化鍍製綠色膜層之製備及量測，碩士論文，國立台灣科技大學化學工程研究所，pp9-10，2017。
24. V. Dehnavi et al., “Effect of duty cycle and applied current frequency on plasma electrolytic oxidation (PEO) coating growth behavior,” Surface and Coatings Technology, vol. 226, pp. 100-107, 2013.
25. A. V. Apelfeld, O. V. Bespalova, Application of the particle backscattering methods for the study of new oxide protective coatings at the surface of Al and Mg alloys, Nuclear Instruments and Methods in Physics Research B, 161, 553, 2000.
26. 鄭天亮，現代塗料與塗裝工程，北京航空航天大學出版社，2003。
27. 陳亮嘉 教授，表面粗糙度及其量測，國立台灣大學機械系，2012。
28. 每日頭條: 揭密鍍晶的接觸角度,2017。
29. 田福助編著，“電化學—理論與應用”，高立圖書，171-193。