Effects of Cr and Sn additives on the martensitic transformation and deformation behavior of Ti-Cr-Sn biomedical shape memory alloys

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:822

Article

Park, Min Soo¹  Chiu, Wan-Ting¹  Nohira, Naoki¹  Tahara, Masaki¹  Hosoda, Hideki¹ 

[1] Tokyo Inst Technol, Inst Innovat Res IIR, Midori Ku, 4259 R2-27,Nagatsuta Cho, Yokohama, Kanagawa 2268503, Japan

关键词: Deformation behavior;    Lattice deformation strain;    Martensitic transformation;    Shape memory alloy;    Superelasticity;    Ti-Cr-Sn alloy;   

DOI  :  10.1016/j.msea.2021.141668

来源: Elsevier

【 摘 要 】

The effects of Cr and Sn additives on the phase constitution, lattice deformation strain, transformation temperature, and deformation behavior of Ti-Cr-Sn alloys were systematically investigated to inform the development of a superelastic alloy with high lattice deformation strain. The addition of Cr and Sn changes the reverse martensitic transformation temperature by -190 K/mol% Cr and -141 K/mol% Sn, respectively. The lattice deformation strains (eta(1), eta(2), and eta(3)) were evaluated in terms of the lattice parameters of the parent beta phase to the martensite alpha '' phases. In addition, the composition range of the alloys that are expected to exhibit superelasticity and high deformation strain near the human body temperature was established based on the composition dependence of lattice deformation strain and transformation temperature. The deformation behavior of Ti-Cr-Sn alloys at room temperature changes from the shape memory effect to superelasticity with increasing Cr and Sn contents. In particular, Ti-2.5Cr-8.55n, Ti-3.0Cr-7.55n, Ti-3.0Cr-8.05n, Ti-3.5Cr-7.05n, and Ti-4.0Cr-6.55n alloys exhibit superelasticity at room temperature and a high lattice deformation strain (eta(2)) that exceeds 6.32%. It is concluded that Cr and Sn are more effective than other beta-stabilizing elements at lowering the martensitic transformation temperature of beta-Ti shape memory alloys without reducing the lattice deformation strain.

【 授权许可】

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