Effect of Annealing on Structure and Mechanical Behavior of an AA2139 Alloy

Abstract:

An AA2139 alloy with a chemical composition of Al–4.35Cu-0.46%Mg–0.63Ag-0.36Mn–0.12Ti (in wt.%) and an initial grain size of about 155 μm was subjected to annealing at 430°C for 3 h followed by furnace cooling. This treatment resulted in the formation of a dispersion of coarse particles having essentially plate-like shape. The over-aged alloy exhibits lower flow stress and high ductility in comparison with initial material in the temperature interval 20-450°C. Examination of microstructural evolution during high-temperature deformation showed localization of plastic flow in vicinity of coarse particles. Over-aging leads to transition from ductile-brittle fracture to ductile and very homogeneous ductile fracture at room temperature.

• Periodical: Materials Science Forum (Volumes 783-786)
• Pages: 258-263
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.783-786.258
• Online since: May 2014
• Authors: Damir Tagirov, Daria Zhemchuzhnikova, Marat Gazizov, Rustam Kaibyshev
• Keywords: Aluminium Alloy, Fracture, High Temperature Deformation, Mechanical Property, Microstructure, Precipitation

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