Table of Contents
Textures and Microstructures
Volume 8 –9
http://dx.doi.org/10.1155/TSM.8-9.233

Texture Changes in an Al–Li Alloy Sheet Superplastically Deformed to High Strains

Materials and Structures Department, Royal Aircraft Establishment, Hants, Farnborough GU14 6TD, UK

Received 25 August 1987; Accepted 23 September 1987

Copyright © 1988 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Changes in the texture and grain shape of an Al–Li alloy sheet superplastically deformed into the shape of a cone have been measured as a function of strain. The starting microstructure was characterised by strong {110}〈112〉 and {123}〈634〉 orientations, together with a number of minor orientations, and an elongated grain shape. Increases and decreases in the intensities of the individual orientations occurred at low values of strain (<0.5) as the elongated grains became equiaxed. Once all the grains were equiaxed, however, there was a continuous decrease in the intensities of all orientations, except for those of some minor orientations which remained essentially constant. The results are explained in terms of slip occurring in the early stages of deformation, because elongated grains will experience difficulty in sliding and rotating, but becoming negligible when grains are equiaxed and are free to slide and rotate. There was some evidence of dynamic recrystallisation but only whilst slip occurred.