Microstructure of 7075 Aluminum Alloy by Homogenization

Abstract:

A 7075 aluminum alloy is widely used in the fields of transportation and aerospace because of its high strength and low density. In this paper, the effect of homogenization annealing on the microstructure of 7075 aluminum alloy was studied. The microstructure and second phase evolution of 7075 aluminum alloy were analyzed by optical microscope (OM), X-ray diffractometer (XRD), scanning electron microscope (SEM), energy spectrometer (EDS) and differential scanning calorimeter (DSC). The results showed that the as-cast microstructure of 7075 aluminum alloy was equiaxial crystal, and non-equilibrium eutectic microstructure Mg(Zn, Cu, Al)₂ produced along the grain boundary. In the subsequent first-order homogenization annealing, part of Mg(Zn,Cu,Al)₂ was converted to Al₂CuMg phase. However, the transformation was not fully complete. Mg(Zn,Cu,Al)₂ was then completely converted to Al₂CuMg phase in the second order homogenization annealing.

• Periodical: Materials Science Forum (Volume 993)
• Pages: 138-145
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.993.138
• Online since: May 2020
• Authors: Yun Fan Dong, Bing Hui Ren, Kang Wang, Jin Feng Leng*
• Keywords: 7075 Aluminum Alloy, Homogenizing Annealing, Microstructure, Precipitated Phase

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