Effect of ECAP on Microstructure and Mechanical Properties of an Al-Mg-Sc Alloy

Abstract:

An Al-4.57%Mg–0.2%Sc was subjected to equal channel angular pressing up to fixed true strains of 1, 2, 4, 8 and 12 at a temperature of 300oC. It was shown that extensive grain refinement occurs in this alloy through continuous dynamic recrystallization. As a result, ECAP can provide the formation of subgrain structure, partially recrystallized structure and fully recrystallized structure. The type of structure evolved is dependent on strain imposed. At ε2, the formation of three-dimensional arrays of low-angle boundaries takes place. Next, in the strain interval from 4 to 8 these low-angle boundaries gradually convert into high-angle boundaries. At ε12, fully recrystallized structure is evolved. Yield stress and ultimate strength gradually increases with increasing strain. Mechanisms of strengthening are discussed.

• Periodical: Materials Science Forum (Volumes 667-669)
• Pages: 949-954
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.667-669.949
• Online since: December 2010
• Authors: Anna Mogucheva, Rustam Kaibyshev
• Keywords: Aluminium Alloy, Ductility, Equal Channel Angular Extrusion (ECAE), Microstructure, Strength

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