Investigation of Mechanical Properties of Aluminum 7075 Alloy via Surface Engineering

Abstract

In this study, MAO process, which is one of the surface coating methods, was applied to 7075-T6 Al alloy in a thin thickness and the relationship between its mechanical properties compared to its uncoated state was investigated. Surface microstructure images of the prepared samples, coating thickness from the cross section and eds analysis were measured by scanning electron microscope (SEM). With the XRD analysis, the peaks in the material on which the coating is made were determined and the difference was examined according to the uncoated state. How the coating affects the dislocation density was investigated. The microhardness value of the samples, which were coated with 2 µm MAO from the surface, was measured according to HV 0.5. The hardness value was thus increased by 50%. The weight loss of coated and uncoated materials was calculated. Despite such a thin coating, the wear resistance has increased approximately 8 times compared to the uncoated state.

Keywords

• Micro Arc Oxidation (MAO)
• 7075 Al Alloy
• Wear
• Dislocation Density

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