Effect of Solution Treatment on Microstructure and Mechanical Properties in an Al-9.3Zn-2.0Mg-1.8Cu Alloy

Abstract:

The microstructure solution treated by various temperatures of 2h in as-extruded Al-9.3Zn-2.0Mg-1.8Cu alloy was investigated by means of optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) analysis. The mechanical properties treated at 465^oC for various times were tested by room temperature tensile mechanical properties test. The results indicated that second phase of the as-extruded alloy mainly consists of Mg (Zn,Cu,Al)₂ and Fe-rich phases. Mg (Zn,Cu,Al)₂ phase completely dissolved into the matrix solution treated at 465^oC or higher for 2h while residual phase was mainly Fe-rich phase. The mechanical properties treated at 465^oC for various time were tested and optimized solution treatment parameter was chosen as 465°C/1.5h.

• Periodical: Materials Science Forum (Volume 877)
• Pages: 606-610
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.877.606
• Online since: November 2016
• Authors: Kai Wen*, Bai Qing Xiong, Yong An Zhang, Xi Wu Li, Zhi Hui Li, Shu Hui Huang, Hong Wei Liu, Hong Wei Yan
• Keywords: Al-Zn-Mg-Cu Alloy, Mechanical Properties, Microstructure, Solution Treatment

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