HARD ANODIC OXIDATION OF A356 ALUMINUM ALLOY
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
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.
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