High-Pressure Torsion (HPT)

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High-Pressure Torsion and Nanostructured Materials Terence G. Langdon, University of Southern California, DMR 0855009 High-pressure torsion (HPT) is a new processing technique that can be used to obtain nanostructured metals. The facility is illustrated on right and the sample, in the form of a disk, is subjected to a high pressure and concurrent torsional straining. A limitation of this technique is that the strain varies across the disk and there is zero strain at the disk center. We have used a two- phase zinc-aluminum alloy to show that the variation in hardness across the disk (as shown by the colors on the right) gradually evolves with increasing numbers of turns. High-Pressure Torsion (HPT) Kawasaki et al. Acta Mater. 58 (2010) 919

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High-Pressure Torsion and Nanostructured Materials Terence G. Langdon, University of Southern California, DMR 0855009. High-Pressure Torsion (HPT). - PowerPoint PPT Presentation

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Page 1: High-Pressure Torsion (HPT)

High-Pressure Torsion and Nanostructured MaterialsTerence G. Langdon, University of Southern California, DMR 0855009

High-pressure torsion (HPT) is a new processing technique that can be used to obtain nanostructured metals. The facility is illustrated on right and the sample, in the form of a disk, is subjected to a high pressure and concurrent torsional straining.

A limitation of this technique is that the strain varies across the disk and there is zero strain at the disk center. We have used a two-phase zinc-aluminum alloy to show that the variation in hardness across the disk (as shown by the colors on the right) gradually evolves with increasing numbers of turns.

This result is important because it demonstrates the potential for achieving homogeneity in disks processed by HPT.

High-Pressure Torsion (HPT)

Kawasaki et al. Acta Mater. 58 (2010) 919

Page 2: High-Pressure Torsion (HPT)

High-Pressure Torsion and Nanostructured Materials Terence G. Langdon, University of Southern California, DMR 0855009

We have presented papers describing our work at the TMS Annual Meeting in Seattle and at international conferences in India, China and Brazil. The upper photo on left shows Dr. Roberto Figueiredo, Dr. Megumi Kawasaki and me at the TMS/ABM meeting in Rio de Janeiro, Brazil, in July 2010. The lower photo shows Megumi presenting her first invited talk at the same meeting.

The other photo was taken when I received the Honorary Medal “De Scientia et Humanitate Optime Meritis” from the President of the Czech Academy of Sciences in Prague in November 2009