Related resources
Full-text held externally
Search for item elsewhere
University researcher(s)
Academic department(s)
The Effect of Dispersoids on the Grain Refinement Mechanisms During Deformation of Aluminium Alloys to Ultra-High Strains
P.J. Apps, M. Berta, and P.B. Prangnell,
Acta Mater. 2005;53:499-511.
Access to files
Abstract
The effect of fine dispersoids on the mechanisms and rate of grain refinement has been investigated during the severe deformation of a model aluminium alloy. A binary Al???0.2Sc alloy, containing coherent Al3Sc dispersoids, of 20 nm in diameter and 100 nm spacing, has been deformed by equal channel angular extrusion to an effective strain of ten. The resulting deformation structures were quantitatively analysed using high-resolution electron backscattered diffraction orientation mapping, and the results have been compared to those obtained from a single-phase Al???0.13Mg alloy, deformed under identical conditions. The presence of fine, nonshearable, dispersoids has been found to homogenise slip, retard the formation of a cellular substructure and inhibit the formation of microshear bands during deformation. These factors combine to reduce the rate of high-angle grain boundary generation at low to medium strains and, hence, retard the formation of a submicron grain structure to higher strains during severe deformation.