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

P. L. Blackwell, P. S. Bate

Research output: Contribution to journalArticle

40 Citations (Scopus)

Abstract

The deformation of AA8090 Al-Li-Mg-Cu-Zr alloy at elevated temperature and slow strain rates has been investigated in uniaxial tension. Under suitable conditions, this material exhibited a high strain-rate sensitivity of the flow stress and was superplastic. This superplastic behavior was obtained in material with an initially elongated grain structure combined with a distribution of similarly oriented grains and low-angle grain boundaries that was not conducive to boundary sliding. Observations of the development of microstructure and of the crystallographic preferred orientation indicated that no significant rigid body translation and little rotation of grain interiors occurred up to strains of about 0.4 and that the probability of relative translation of grain interiors up to strains of at least 1 was low. The changes of structure observed could be accounted for by a combination of grain growth and grain rotation. The consequence of these observations on the grain switching and grain boundary sliding mechanisms generally assumed to operate during superplastic deformation is discussed, with the conclusion that those mechanisms may not be wholly appropriate for explaining high rate sensitivity in this material over the range of strain rates investigated.
Original languageEnglish
Pages (from-to)1085-1093
Number of pages9
JournalMetallurgical and Materials Transactions A
Volume24
Issue number5
DOIs
Publication statusPublished - 31 May 1993

Keywords

  • metallurgical transaction
  • flow stress
  • rate sensitivity
  • superplastic deformation
  • misorientation distribution

Fingerprint Dive into the research topics of 'The absence of relative grain translation during superplastic deformation of Al-Li-Mg-Cu-Zr alloy'. Together they form a unique fingerprint.

Cite this