An investigation of microstructural evolution during equal-channel angular pressing

Y. Iwahashi, Zenji Horita, M. Nemoto, T. G. Langdon

Research output: Contribution to journalArticle

810 Citations (Scopus)

Abstract

Experiments were conducted to investigate the development of an ultra-fine grain size during equal-channel angular (ECA) pressing of high purity aluminum with an initial grain size of ∼1.0 mm. The results show that, under ECA pressing conditions giving a strain of ∼1.05 on each passage through the die, the microstructure is reasonably homogeneous after a single pressing and consists of parallel bands of elongated subgrains, having an average length of ∼4 μm, and these subgrains are further divided by boundaries with very low angles of misorientation. Repetitive pressings were conducted on the same samples, up to a total of 10 passages through the die, with the samples pressed either without rotation (route A) or after rotating through 180° between each pressing (route C). It is demonstrated that the misorientations of the subgrain boundaries increase with repetitive pressings until ultimately both routes lead to a similar equiaxed ultra-fine grain size of ∼1 μm after 10 pressings, but the microstructural evolution is enhanced using route C where there is a more rapid transition into an array of high angle grain boundaries. The results suggest that, at least for high purity aluminum, an ultra-fine microstructure close to optimum may be obtained after only 4 pressings provided the sample is rotated through 180° between each pressing.

Original languageEnglish
Pages (from-to)4733-4741
Number of pages9
JournalActa Materialia
Volume45
Issue number11
DOIs
Publication statusPublished - Jan 1 1997

Fingerprint

Equal channel angular pressing
Microstructural evolution
Aluminum
Microstructure
Grain boundaries
Experiments

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Ceramics and Composites
  • Polymers and Plastics
  • Metals and Alloys

Cite this

An investigation of microstructural evolution during equal-channel angular pressing. / Iwahashi, Y.; Horita, Zenji; Nemoto, M.; Langdon, T. G.

In: Acta Materialia, Vol. 45, No. 11, 01.01.1997, p. 4733-4741.

Research output: Contribution to journalArticle

Iwahashi, Y. ; Horita, Zenji ; Nemoto, M. ; Langdon, T. G. / An investigation of microstructural evolution during equal-channel angular pressing. In: Acta Materialia. 1997 ; Vol. 45, No. 11. pp. 4733-4741.
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