168 Int. J. Microstructure and Materials Properties, Vol. 7, Nos. 2/3, 2012 Copyright © 2012 Inderscience Enterprises Ltd. Effect of high-pressure torsion processing on microstructure and mechanical properties of a novel biomedical β-type Ti-29Nb-13Ta-4.6Zr after cold rolling Hakan Yilmazer Department of Materials Science, Graduate School of Engineering, Tohoku University, Aoba-ku Katahira 2-1-1 Sendai 980-8577, Japan Fax: +81-22-215-2553 E-mail: hakan@imr.tohoku.ac.jp Mitsuo Niinomi* Institute for Materials Research, Tohoku University, Aoba-ku Katahira 2-1-1 Sendai 980-8577, Japan Fax: +81-22-215-2553 E-mail: niinomi@imr.tohoku.ac.jp *Corresponding author Toshikazu Akahori Department of Materials Science and Engineering, Faculty of Materials Science and Technology, Meijo University, 1-501 Shiogamaguchi, Tempa-ku, Nagoya 468-8502, Japan Fax: +81-52-832-1172 E-mail: akahori@meijo-u.ac.jp Masaaki Nakai Institute for Materials Research, Tohoku University, Aoba-ku Katahira 2-1-1 Sendai 980-8577, Japan Fax: +81-22-215-2553 E-mail: nakai@imr.tohoku.ac.jp