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Licensed Unlicensed Requires Authentication Published by De Gruyter June 11, 2013

Mechanical properties of pure titanium and Ti-6Al-4V alloys with a new tailored nano/meso hybrid microstructure

  • Hiroshi Fujiwara , Tatsuya Sekiguchi and Kei Ameyama


Pure titanium and Ti-6Al-4V alloy powders are treated by a mechanical milling process, which is one of the severe plastic deformation processes. The mechanical milling enables to produce a nano-grain microstructure very easily and has been applied to many powder materials. The bimodal microstructure in those mechanically milled powders is composed of a nano-grain structure with a grain size of about 50 nm in the surface-near region and of a work-hardened microstructure in the core region of the powder. We applied the hot roll sintering process to pure titanium and to Ti-6Al-4V mechanically milled powders. These compacts have a hybrid microstructure that consists of nano-grain structure with grain sizes of 200 to 500 nm and a micron size meso-grain structure. The hybrid microstructure materials demonstrate enhanced mechanical properties compared to conventional materials.

* Correspondence address, Professor Kei Ameyama, Department of Mechanical Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu 525-8577, Japan, Tel. and Fax: +81 77 561 2756, E–mail:


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Received: 2008-8-27
Accepted: 2009-2-11
Published Online: 2013-06-11
Published in Print: 2009-06-01

© 2009, Carl Hanser Verlag, München

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