Effect of Carbon Addition of Shape Memory Properties of TiNb Alloys

Abstract:

In order to increase critical stress for slip in Ti-Nb base shape memory alloys, strengthening by carbon additions (0.2 and 0.5mass%C) to Ti-27mol%Nb was investigated. It was found that all the alloys were  (bcc) phase at room temperature, and TiC existed in C-added alloys. The grain size was decreased with carbon content due to grain boundary pinning. Texture measurement revealed that strong {112}<110> recrystallization texture was formed in C-free alloy and that weak {001}<110> texture in C-added alloys. Tensile tests revealed that clear superelasticity appeared in C-free alloy but that stress-induced martensitic transformation seems to be suppressed by TiC in C-added alloys. The critical stress for slip was linearly increased by carbon content. Then, carbon addition affects the shape memory properties of TiNb alloys, and is effective to enhance the critical stress for slip.

• Periodical: Materials Science Forum (Volumes 638-642)
• Pages: 2046-2051
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.638-642.2046
• Online since: January 2010
• Authors: Hideki Hosoda, Yosuke Horiuchi, Tomonari Inamura, Kenji Wakashima, H.Y. Kim, Shuichi Miyazaki
• Keywords: Carbon Addition, Critical Stress For Slip, Grain Size, Shape Memory Properties, Strengthening, Superelasticity, Texture, TiC, TiNb

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