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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

Abstract

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:

References

[1] K.Ameyama: Scripta Mater.38 (1998) 517.10.1016/S1359-6462(97)00465-XSearch in Google Scholar

[2] K.Ameyama, M.Hiromitsu, N.Imai: Tetsu-to-Hagane84 (1998) 357.Search in Google Scholar

[3] H.Fujiwara, M.Ishida, H.Inomoto, K.Ameyama, in: M. Lamberigts (Ed.), 2nd International Conference on Thermomechanical Processing of Steels, CRM (2004) 405.Search in Google Scholar

[4] M.Umemoto: Mater. Trans.44 (2003) 1900.10.2320/matertrans.44.1900Search in Google Scholar

[5] H.Fujiwara, H.Inomoto, K.Ameyama: Tetsu-to-Hagane91 (2005) 839.Search in Google Scholar

[6] H.Inomoto, H.Fujiwara, K.Ameyama, in: M.J. Zehetbauer, R.Z. Valiev (Eds.), Proc. of the 2nd International Conference on Nanomaterials by Severe Plastic Deformation, Wiley-VCH (2004) 571.10.1002/3527602461.ch10fSearch in Google Scholar

[7] E.Ma: Scripta Mater.49 (2003) 663.10.1016/S1359-6462(03)00396-8Search in Google Scholar

[8] K.Ohishi, H.W.Zhang, T.Ohkubo, K.Hono: Mater. Sci. Eng. A456 (2007) 20.Search in Google Scholar

[9] H.Fujiwara, R.Akada, A.Noro, Y.Yoshita, K.Ameyama: Mater. Trans.49 (2008) 90.Search in Google Scholar

[10] H.Fujiwara, R.Akada, Y.Yoshita, K.Ameyama: Mater. Sci. Forum503–504 (2006) 227.Search in Google Scholar

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

© 2009, Carl Hanser Verlag, München