Superplastic Deformation of Ultrafine Grained Al Alloy Processed by ECAP and Post-Rolling

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Superplastic behavior of an ultrafine grained (UFG) 5154 Al alloy processed by ECAP and cold rolling (ECAP+CR sample) was investigated and compared with that of the alloy processed by only ECAP without rolling (ECAP sample) in the strain rate range of 10-4~5×10-1 s-1 at 723 K. Processing of the ECAP+CR sample consisted of ECAP of 4 passes, which was less than that showing the optimum microstructure for high strain rate superplasticity of UFG Al alloys (i.e. 8 passes), with route Bc and subsequent cold rolling (70% thickness reduction). The superplastic elongation was remarkably enhanced by post-rolling. An analysis of the mechanical data revealed that deformation of the ECAP+CR sample was dominated by grain boundary sliding, but dislocation viscous glide was the main deformation mechanism for the ECAP sample. In addition, cavitation in the ECAP+CR sample was insignificant up to ∼300% elongation.

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Periodical:

Materials Science Forum (Volumes 503-504)

Edited by:

Zenji Horita

Pages:

119-124

Citation:

K. T. Park et al., "Superplastic Deformation of Ultrafine Grained Al Alloy Processed by ECAP and Post-Rolling", Materials Science Forum, Vols. 503-504, pp. 119-124, 2006

Online since:

January 2006

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$38.00

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