Effect of Cold Rolling on Microstructure and Mechanical Properties of an Al-Mg-Sc-Zr Alloy

Abstract:

The microstructural evolution and mechanical properties of an Al-5.4Mg-0.4Mn-0.2Sc-0.09Zr alloy subjected to cold rolling with a total strain up to ~1.6 was studied using high resolution EBSD analysis and TEM. It was shown that cold rolling induces elongation of initial grains and the formation of deformation bands along rolling direction in addition to dramatic increase in density of lattice dislocations. Two types of deformation bands evolve. Deformation bands initially bounded by low-angle boundaries (LABs) with misorientation higher than 2^o and spacing ranging from 0.8 to 4 μm gradually transform to lamellas delimited by high-angle boundaries (HABs). Thin deformation bands delimited by LABs with misorientation of 2^o or less evolve within these coarse bands. First type of deformation bands is subdivided due to mutual intersection with second order deformation bands or shear bands to elongated crystallite evolving to micron scale grains with strain. The thin deformation bands may be also subdivided to nanoscale crystallites. It was shown that the formation of well-defined deformation bands yield very high anisotropy in strength and ductility, while a strong increase in lattice dislocation density with strain diminishes this anisotropy.

• Periodical: Advanced Materials Research (Volume 922)
• Pages: 388-393
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.922.388
• Online since: May 2014
• Authors: Vladislav Kulitskiy*, Sergey Malopheyev, Rustam Kaibyshev
• Keywords: Aluminium Alloy, Anisotropy of Mechanical Properties, Cold Rolling, Deformation Structure

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