Superplastic Behavior of an Al-Cu-Mg-Mn-Ag Alloy

Abstract:

The superplastic properties and microstructural evolution of a commercial Al-4.4%Cu-0.5%Mg-0.4%Mn-0.5%Ag-0.1%Ti alloy were examined under tension at temperatures ranging from 450 to 520°C and strain rates ranging from 6.9x10^-5 to 6.9x10^-2s^-1. The refined microstructure with an average grain size of about 11m was produced in thin sheets by a commercially viable thermomechanical process. The highest elongation to failure of 540% was attained at a temperature of 500°C and an initial strain rate of 6.9x10^-4 s^-1 with the corresponding strain rate sensitivity coefficient of 0.55. The microstructural evolution during superplastic deformation of the aluminum alloy has been studied quantitatively. Processing at temperatures above 475°C and strain rate below 1.4x10^-3s^-1 resulted in fracturing almost without necking with cavitation playing a major role in the failure. In contrast, at low temperatures and/or high strain rates, fracture occurred in a ductile manner by localized necking. The relationship between superplastic ductility and microstructural evolution is analyzed.

• Periodical: Materials Science Forum (Volume 870)
• Pages: 185-190
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.870.185
• Online since: September 2016
• Authors: F.F. Musin*, B.O. Bolshakov, E. Domracheva
• Keywords: Aluminum Alloys, Mechanical Properties, Microstructure, Superplastic Deformation

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