The absence of relative grain translation during superplastic deformation of an Al-Li-Mg-Cu-Zr alloy

Effect of layered microstructure on superplastic forming property of AA8090 Al–Li alloy

“…The S layer already contains wellrecrystallized equiaxed microstructure, which is known to be favorable for superplastic deformation. The unrecrystallized and elongated grains in the M layer evolve as a function of strain into equiaxed and recrystallized grains through the process of deformation induced continuous recrystallization (DICR) [16,18,19].…”

“…These microstructural changes profoundly affect the strain rate sensitivity of the material [18]. The effect of such microstructural evolution on uniaxial superplastic deformation properties were investigated earlier [18,19] but the same is not reported during superplastic forming (SPF) of AA8090 Al-Li alloy [20,21]. Therefore, in the present work, an attempt is made towards understanding the thickness variation resulting from superplastic forming of AA8090 Al-Li sheets of different starting microstructures along its thickness.…”

Effect of local strain distribution on concurrent microstructural evolution during superplastic deformation of Al–Li 8090 alloy

“…After that the deformation mechanism is considered to be grain boundary (GB) sliding [7] as common in other superplastic materials. However, Blackwell and Bate [8] argued that the dislocation motion plays important role as a dominant mechanism through out the deformation of Al Á/Li 8090 alloy. This led to the study of texture evolution in this alloy.…”

“…Recently Wang et al [18] did a quantitative analysis on the effect of local strain on the cavitation behavior of 3Y-TZP. No such study was made in the superplastic Al Á/Li 8090 alloy, which has layered microstructure [8]. Therefore, the aim of the present work is to characterize quantitatively the effect of local strain and strain rate variation on microstructural evolution (comprising of grain growth and cavitation) during superplastic deformation of AlÁ/Li 8090 alloy.…”

Anisotropy in flow and microstructural evolution during superplastic deformation of a layered-microstructured AA8090 Al–Li alloy

“…Such gradients in microstructure and microtexture, from the surface to the midthickness layers, may influence the superplastic flow behavior and the nature of anisotropy differently from the situation where microstructure and microtexture throughout the thickness of the tensile specimen were identical. While some comparison in the superplastic behavior of CL and FL material was reported [13], there does not appear to be any attempt made towards investigating the anisotropy in superplastic flow of surface and CL material of distinct microstructures and microtextures. Therefore, the aim of the present work was to investigate the superplastic flow behavior of and the microstructural evolution in the SLs, the midthickness layers and the FL material of superplastic forming (SPF) grade AA8090 Al Á/Li alloy at different orientations, with respect to the rolling direction (RD).…”