Influence of Aging Temperature on Precipitation Kinetics, Morphology and Hardening Behavior of Al-7475 Alloy

  • E. F. Abo ZeidEmail author
Research Article - Physics


In this research, the precipitation hardening behavior of Al-7475 alloy is investigated by a comprehensive experimental study on the relationship between thermal aging and evaluation of the kinetics and hardening properties of the alloy. The investigation was carried out using X-ray diffraction analysis (XRD), differential scanning calorimetry, scanning and transmission electron microscopy investigations and Vickers hardness (HV) test. The XRD results show that increasing the aging temperature, from 273 to 620 K, enhances the coarsening and evolution of precipitates which leads to an increase in the particle size. The thermal analysis shows the precipitation kinetics of the observed phases such as \(\upeta '\), \({T}'\), and \(\upeta \), based on the correlation between migration and diffusion of spread atoms in the Al matrix. In addition, the TEM micrographs indicate that needle-shaped precipitates distinguish the development of \(\upeta '\) and/or \({T}'\)- precipitates which at most contribute to the material strengthening. Moreover, the reaction order values of \(\upeta '\) and \(\upeta \)-precipitate nucleation indicate that the developed phases are radially grown.


Al-7475 alloy Precipitation hardening Thermal Aging DSC \(\hbox {Mg}_{2}\)Zn phase Structural 


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My thanks go to Dr. Alaa M. Abd-Elnaiem (Physics Department, Faculty of Science, Assiut University, Assiut 71516, Egypt) for his effective contribution and valuable help in the interpretation of some of the results.

Compliance with ethical standards

Conflict of interest

The author declares that he has no conflict of interest.


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© King Fahd University of Petroleum & Minerals 2019

Authors and Affiliations

  1. 1.Physics Department, Faculty of ScienceAssiut UniversityAssiutEgypt

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