Microstructure Evolution and Properties of 7A56 Aluminum Alloy by Homogenization

Abstract:

The microstructure evolution and properties of Al-matrix in homogenized 7A56 alloy were investigated by scanning electron microscope (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), electrical conductivity and hardness test. The second phases in as-cast 7A56 alloy consisted of AlZnMgCu, Al₂Cu and Al₇Cu₂Fe. With the homogenization temperature increasing, more non-equilibrium phase AlZnMgCu was dissolved into Al-matrix. The diffusion of alloying elements from AlZnMgCu phase into Al-matrix leads to a decrease of electrical conductivity and an increase of hardness. The lattice constant of α-Al has an increases of 0.0019 Å, 0.0032 Å and 0.0053 Å after 380°C/24h,430°C/24h,and 470°C/24 h treatment,respectively.

• Periodical: Materials Science Forum (Volume 898)
• Pages: 153-158
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.898.153
• Online since: June 2017
• Authors: Da Xu, Zhi Hui Li*, Guo Jun Wang, Long Bing Jin, Hong Wei Yan, Xi Wu Li, Yong An Zhang, Bai Qing Xiong
• Keywords: 7A56 Aluminum Alloy, AlZnMgCu Phase, Dissolution, Homogenization, Lattice Distortion

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