Textured Zn–1.1%Al alloy, whose pole figure was characterized by two 0002 components, was subjected to superplastic deformation in different directions. One of the straining directions was favourable to basal slip while the other was not. The contribution of grain-boundary sliding to the total deformation was estimated on the basis of measurements of the vertical component of sliding. The material showed significant anisotropies of flow stress and grain-boundary sliding. Deformation in the direction which was unfavourable to intragranular slip resulted in a much higher flow stress and the contribution of grain-boundary sliding to the total strain than did deformation in the favourable direction. These results demonstrated an independence of grain-boundary sliding and intragranular slip during superplastic flow.

The Influence of Crystallographic Texture on Grain Boundary Sliding during Superplastic Deformation in Zn–1.1%Al Alloy. A.D.Sheikh-Ali: Materials Science and Engineering A, 2008, 475[1-2], 308-11