Home Properties of Alumina Coating Formed by Microarc Oxidation Technique on 6061 Aluminum Alloy
Article
Licensed
Unlicensed Requires Authentication

Properties of Alumina Coating Formed by Microarc Oxidation Technique on 6061 Aluminum Alloy

  • Aytekin Polat , Metin Usta , Murat Makaraci , Ali Ata and Zakir Tas
Published/Copyright: May 5, 2013
Become an author with De Gruyter Brill
Submit Manuscript Author Information
Practical Metallography
From the journal Practical Metallography Volume 45 Issue 12

Abstract

In this study, thick and hard alumina coatings were produced on 6061-T6 Al alloy substrates for different oxidation times and current densities by using of microarc oxidation (MAO) technique in an alkali-silicate electrolytic solution. The influence of oxidation time and current density on the kinetics, phase composition, hardness, surface roughness and structure of the coating were investigated. It is found that the kinetics of coating mainly depends on applied current density and oxidation time. The XRD results revealed that the coatings are composed of mainly α-Al2O3, γ-Al2O3 and mullite phase. The relative ratio of harder and denser α-Al2O3 phase increases with increasing current density and oxidation time. For the same coating time, the position of maximum hardness of coatings moves away from the substrate-coating interface to the coating surface with increasing current density. The surface roughness of coating is a function of coating thickness and increases with increasing deposition time and current density. The surface micro hardness of Al 6061-T6 alloy substrate was increased up to 2200 HV hardness after the coating.

Kurzfassung

Im Rahmen dieser Untersuchung wurden Aluminiumbeschichtungen großer Dicke und Härte auf einer 6061-T6- Aluminiumlegierung bei verschiedenen Oxidationszeiten sowie Stromdichten mit Hilfe der Microarc-Oxidation (MAO) in einer Alkali-Silikat-Elektrolytlösung hergestellt. Es wurde der Einfluss von Oxidationsdauer und Stromdichte auf Kinetik, Phasenzusammensetzung, Härte, Oberflächenrauheit und Gefüge der Beschichtung untersucht. Die Ergebnisse erbrachten, dass die Kinetik der Beschichtung in starkem Maße von Stromdichte und Oxidationsdauer abhängt. Die Ergebnisse der Röntgendiffraktometrie erbrachten, dass die Beschichtungen hauptsächlich aus α-Al2O3, γ-Al2O3 und einer Mullit-Phase bestehen. Der relative Anteil der härteren und dichteren α-Al2O3 -Phase erhöht sich mit zunehmender Stromdichte und Oxidationsdauer. Bei gleicher Beschichtungszeit verschiebt sich die Position der maximalen Härte der Beschichtungen mit steigender Stromdichte von der Trennfläche der Trägermaterialbeschichtung zur Beschichtungsfläche. Die Oberflächenrauheit der Beschichtung ist eine Funktion der Beschichtungsdicke und steigt mit zunehmender Ablagerungszeit und Stromdichte. Die Oberflächenmikrohärte des Legierungs-Trägermateriales Al 6061-T6 stieg auf 2200 HV Härte nach der Beschichtung.

∗ Corresponding author/Korrespondierender Autor:

Aytekin Polat born 1969, Turkey, MSc degree in mechanical engineering from University of Pittsburgh/USA, he now works as a research assistant in Gebze Institute of Technology. Research area: Fracture mechanics, microstructure and mechanical properties of aluminum alloys, coatings, wear and corrosion behavior of coatings.

Metin Usta Associate Professor Usta received the B.S. in metallurgy from Istanbul Technical University in 1992. He finished his Ph.D at Rensselaer Polytechnic Institute in 2001. He joined Gebze Institute of Technology. He is author or co-author of 25 scientific papers, in the areas of metallic materials, coatings and biomaterials.

Literatur/References

1 Van, T.B.; Brown, S.D.; Wirtz, G.P.: Am. Ceram. Soc. Bull. 56 (1977) 6, 563–566Search in Google Scholar

2 Krysmann, W.; Kurze, P.; Dittrich, K.H.; Schneider, H.G.: Cryst. Res. Technol. 19 (1984) 7, 973–97910.1002/crat.2170190721Search in Google Scholar

3 Yerokhin, A.L.; Lyubimov, V.V.; Ashitkov, R.V.: Ceram. Int. 24 (1998) 1–610.1016/S0272-8842(96)00067-3Search in Google Scholar

4 Yang, G.L.; Lu, X.Y.; Bai, Y.Zh.H.F.Cui, Z.S.Jin, J.: Alloys Comp. 345 (2002) 196–20010.1016/S0925-8388(02)00289-XSearch in Google Scholar

5 Yerokhin, A.L.; Nie, X.; Leyland, A.; Matthews, A.: Surface and Coatings Technology, 142-144 (2001) 1155–1157Search in Google Scholar

6 Voevodin, A.A.; Yerokhin, A.L.; Lyubimov, V.V.; Donley, M.S., Zabinski, J.S.: Surface and Coatings Technology, 86–87 (1996) 516–52110.1016/S0257-8972(96)03069-1Search in Google Scholar

7 Dearnley, P.A.; Gummersbach, J.; Weiss, H.; Ogwu, A.A.; Davies, T.J.: Wear225–229 (1999) 127–134Search in Google Scholar

8 Nie, X.; Meletis, E.I.; Jiang, J.C.; Leyland, A.; Yerokhin, A.L.; Matthews, A.: Surface and Coatings Technology, 149 (2002) 245– 25110.1016/S0257-8972(01)01453-0Search in Google Scholar

9 Nie, X.; Leyland, A.; Song, H.W.; Yerokhin, A.L.; Dowey, S.J.; Matthews, A.: Surface and Coatings Technology, 116–119 (1999) 1055–106010.1016/S0257-8972(99)00089-4Search in Google Scholar

10 Jun, T.; Zhuangzi, L.; Shangkui, Q.; Xiaojun, S.: Surface and Coatings Technology, 154 (2002) 1 –710.1016/S0257-8972(01)01671-1Search in Google Scholar

11 Romanovsky, E.A.; Bespalova, O.V.; Borisov, A.M.; et al,: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 161-163 (2000) 553–557Search in Google Scholar

12 Yerokhin, A.L.; Nie, X.; Leyland, A.; Matthews, A.; Dowey, S.J.: Surf. Coat. Technol. 122 (1999) 7310.1016/S0257-8972(99)00441-7Search in Google Scholar

13 KlapkivM.D.: Mater. Sci. 31 (1995) 49410.1007/BF00559144Search in Google Scholar

14 Sundararajan, G.; Rama Krishna, L.: Surface and Coatings Technology, 167 (2003) 26910.1016/S0257-8972(02)00918-0Search in Google Scholar

15 Long, B.Y.; Wu, H.H.; Long, B.H.; et al. J. Jilin Univ. (Science Edition)43 (1) (2005) 68 (in Chinese)Search in Google Scholar

16 Wu, H.H.; Lu, X.Y.; Long, B.H.; Wang, X.Q.; et al. Mater. Lett. 59 (2005) 37010.1016/j.matlet.2004.10.019Search in Google Scholar

17 Wu, H.H.; Jin, Z.S.; Long, B.Y.; Yu, F.R.; Lu, X.Y.: Chin. Phys. Lett. 20 (10) (2003) 181510.1088/0256-307X/20/10/345Search in Google Scholar

18 Krysman, W.; Kurze, P.; Dittrich, H.G.: Crystal. Res. Technol. 19 (1984) 973–10.1002/crat.2170190721Search in Google Scholar

19 Yerokhin, A.L.; Snizhko, L.O.; Gurevina, N.L.; Leyland, A.; Pilkington, A.; Matthews, A.: Surface and Coatings Technology, 177–178 (2004) 779Search in Google Scholar

20 Rama Krishna, L.; Somaraju, K.R.C.; Sundararajan, G.: Surface and Coatings Technology, 163–164 (2003) 484Search in Google Scholar

21 TianJ.; Luo, Z.; Qi, S.; Sun, X.: Surface and Coatings Technology, 154 (2002), 1-710.1016/S0257-8972(01)01671-1Search in Google Scholar

Received: 2008-2-6
Accepted: 2008-7-10
Published Online: 2013-05-05
Published in Print: 2008-12-01

© 2008, Carl Hanser Verlag, München

Articles in the same Issue

  1. Contents/Inhalt
  2. Inhalt / Contents
  3. Technical Contributions/Fachbeiträge
  4. Digital Light Microscopy of Macroporous Ceramics Processed by Consolidation Casting with Mixtures of Native Starches
  5. Properties of Alumina Coating Formed by Microarc Oxidation Technique on 6061 Aluminum Alloy
  6. The Microstructural Characterization of Dual Phase Steel with the Method of Chemical Etching
https://doi.org/10.3139/147.100406

Articles in the same Issue

  1. Contents/Inhalt
  2. Inhalt / Contents
  3. Technical Contributions/Fachbeiträge
  4. Digital Light Microscopy of Macroporous Ceramics Processed by Consolidation Casting with Mixtures of Native Starches
  5. Properties of Alumina Coating Formed by Microarc Oxidation Technique on 6061 Aluminum Alloy
  6. The Microstructural Characterization of Dual Phase Steel with the Method of Chemical Etching
Sign up now to receive a 20% welcome discount
Institutional Access
How does access work?
Have an idea on how to improve our website?
Please write us.
© 2025 De Gruyter Brill
Downloaded on 4.11.2025 from https://www.degruyterbrill.com/document/doi/10.3139/147.100406/html
Scroll to top button