Development of intense plastic strain and ultrafine grains in thicker samples processed by high-pressure torsion and high-pressure sliding

Hideaki Iwaoka, Tadayoshi Fujioka, Yosuke Harai, Zenji Horita

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3 Citations (Scopus)


Intense plastic strain is imparted into disk-and ring-shape samples using high-pressure torsion (HPT) which is known as a typical process of severe plastic deformation. The grain size is refined to the submicrometer and/or nanometer range. The grain refinement is also achieved using high-pressure sliding (HPS) which was developed recently for rectangular sheet samples under high pressure as in HPT. However, the samples with the thickness thinner than 1 mm are usually used for both HPT and HPS processes but no attempt has been made for samples with the thickness thicker than 1 mm. This study is then initiated to investigate how homogeneously the strain is developed and the grain refinement is achieved in the thicker samples. High purity Al (99.99%) is used with ring-shape and rectangular sheet samples having thicknesses of 2 and 4 mm. It is shown that a region of intense plastic strain develops at the center height and expands to both upper and lower edges with straining. The grain refinement is achieved at such an intense plastic region with dislocation-free grains with the sizes of a few micrometers.

Original languageEnglish
Pages (from-to)412-418
Number of pages7
JournalNippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals
Issue number7
Publication statusPublished - Jul 1 2011


All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Mechanics of Materials
  • Metals and Alloys
  • Materials Chemistry

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