HARD ANODIC OXIDATION OF A356 ALUMINUM ALLOY

Year 2021, Volume: 4 Issue: 1, 44 - 50, 30.06.2021

Aziz Barış Başyiğit Halil Kurt

Abstract

ASTM A356 (ISO AlSi7Mg) aluminum alloys are widely used in automotive and aircraft industries but they are selected mainly as automobiles wheel rim materials. They are composed of magnesium and silicon elements for improving corrosion and strength properties. Wheel rim materials are often electroplated by rim paints for decorative views and durability considerations. In this study; aluminum A356 alloy was coated by hard anodic oxidation method. 14 samples are prepared from an automobiles original 14 inch A356 aluminum alloy wheel rim. Samples are machined by 4x20x20 mm in dimensions for hard anodic oxidation. Three different case depths of hard anodic oxidation about 45, 65 and 90µm are applied on samples. Micro-structural investigations, micro-hardness surveys and the case depths of samples are thoroughly studied. The applicability of hard anodic oxidation method on wheel rim material A356 alloy is examined. The micro-structural surveys and micro-hardness tests proved that A356 aluminum alloy samples were hard anodic oxidized up to 90µm in coating thickness. 

Keywords

Aluminum alloys, Aluminum A356 alloy, Hard anodic oxidation

Thanks

Authors would like to express their deepest appreciation to organizing committee of TICMET20 in the selection of this study which was presented in the conference organized on 05-07 November 2020 at Gaziantep University. Authors also express their respects to MKEK Armament Factory Heat Treatment Department Staff especially Mr. Mehmet Kalkan for precious laboratory supports.

References

• [1]. Standard Specification for Aluminum-Alloy Sand Castings, ASTM B26/B26 M-18E1, ASTM International, 2018.
• [2]. Aluminum and Aluminum Alloy Castings Chemical Composition and Mechanical Properties, BS EN 1706, 2010.
• [3]. Properties and Selection; Non-Ferrous Alloys and Special Purpose Materials, ASM International, ASM Handbook Volume 2, pp. 618-627, 1990.
• [4]. Surface Engineering, ASM Handbook, Volume 5, p.1416, 1994.
• [5]. Metallography and Microstructures, ASM Handbook Volume 9, pp. 1691-1694, 1696, 2004.
• [6]. Metallic and Other Inorganic Coatings-Vickers and Knoop Micro-Hardness Tests, TS 6503 EN-ISO 4516, 2003.
• [7]. Metallic Materials-Vickers Hardness Test-Part ; Test Method, ISO 6507-1, 2018.
• [8]. Standard Test Methods for Vickers Hardness and Knoop Hardness of Metallic Materials, ASTM E92, 2017.
• [9]. Standard Test Methods for Micro-Indentation Hardness of Materials, ASTM E 384, 2017.
• [10].Elkilany H.A. et.al., Influence of Hard Anodizing on the Mechanical and Corrosion Properties of Different Aluminum Alloys, Metallography Microstructure and Analysis, Volume 8, Issue 6, pp.861-870, doi: 10.1007/s13632-019-00594-5, 2019.
• [11]. Mahmud Eri et.al., Characterizations of Cladded 6082-T6 Aluminum Alloy Through Hard Anodizing, Science of Advanced Materials, Volume 12, Issue 7, pp.1034-1045, doi: 10.1166/sam.2020.3758, 2020.
• [12]. Kwolek P. et.al., Tribological Properties of the Oxide Coatings Produced onto 6061 T6 Aluminum Alloy in the Hard Anodizing Process, Journal of materials Engineering and Performance, Volume 27, Issue 7, pp.3268-3275, doi: 10.1007/s11665-018-3241-8, 2018.
• [13]. E. Ergül , H. Kurt , M. Oduncuoğlu and C. Çi̇vi̇ , "Wear Properties of Al-Cu-Mg Composites Reinforced with MGO and MWCNT under Different Loads", The International Journal of Materials and Engineering Technology, Volume. 2, Issue. 2, pp. 70-75, 2020.
• [14].B. Baksan , İ. Çeli̇kyürek and Y. Kılıç , "Effect of Secondary Aging of EN AC 43200 Aluminum Alloy to Mechanical Properties", The International Journal of Materials and Engineering Technology, Volume. 3, Issue. 1, pp. 16-20, 2020.