The Effect of Dispersoids and Processing Route on Grain Refinement During Deformation of Aluminium Alloys deformed by ECAP

Marco Berta ,  Philip B. Prangnell 

University of Manchester - School of Materials Science - Materials Science Centre, grosvenor street, Manchester M1 7HS, United Kingdom


The effect of fine second-phase non-shearable dispersoids on the grain refinement of aluminium severely deformed by ECAE through routes A and Bc (+90degrees rotation) has been studied using a model Al-0.2%Sc alloy. The microstructure development with strain in the dispersoid containing alloy was compared to a single phase alloy, using high resolution EBSD analysis. The effect of the processing route was investigated for both materials using ECAE die angles of 90 degrees and 120 degrees.
The presence of fine dispersoids was found to inhibit the development of new high-angle grain boundaries and the formation of a fine grain structure with route A. This effect was enhanced by rotation of the sample using route Bc. The mechanisms of responsible for the different rates of grain refinement and their interaction with the processing variables are discussed.


Presentation: oral at E-MRS Fall Meeting 2005, Symposium I, by Marco Berta
See On-line Journal of E-MRS Fall Meeting 2005

Submitted: 2005-05-13 11:15
Revised:   2009-06-07 00:44