Mechanical and microstructural characterization of new nickel-free low modulus beta-type titanium wires during thermomechanical treatments
Author
Guillem Martí, Jordi
Herranz-Diez, Carolina
Shaffer, J.E.
Gil Mur, Francisco Javier
Manero Planella, José María
Publication date
2015-06-11ISSN
0921-5093
Abstract
NiTi alloy is the only practical shape memory alloy (SMA) in biomedical use because of its excellent mechanical stability and functionality. However, it is estimated that between 4.5% and 28.5% of the population are hypersensitive to nickel metal, with a higher prevalence in females. Therefore, developing nickel-free low modulus beta-type titanium alloys showing shape memory or super elastic behavior would have a great interest in the biomaterials field. Homogeneous 127 mu m diameter Ti25Hf21Nb wires were produced and compared to straight annealed Ti-50.8 at% Ni (Nitinol) and 90% cold-drawn 316L wires. Microstructural changes taking place during the heat treatment of cold-worked Ti25Hf21Nb wires were investigated. Large plastic deformation during wire drawing and subsequent annealing led to nano-crystallization and amorphization which may contribute to the observed superelasticity. Mechanical properties were characterized using cyclic uniaxial tension and rotary beam fatigue test modes. A modulus of elasticity of less than 60 GPa and axial recoverable strain of greater than 3% were observed with stress hysteresis resembling a reversible stress-induced martensitic transformation at higher temperatures. The new Ti25Hf21Nb alloy is an important candidate for developing Ni-free SMAs in the future.
Document Type
Article
Document version
Accepted version
Language
English
Subject (CDU)
62 - Engineering. Technology in general
Keywords
Aliatges
Elasticitat
Materials biomèdics
Titani -- Aliatges
Aleaciones
Elasticidad
Materiales biomédicos
Titanio -- Aleaciones
Alloys
Elasticity
Biomedical materials
Titanium alloys
Pages
33
Publisher
Elsevier
Collection
636;
Is part of
Materials Science and Engineering: A
Citation
Guillem Martí, Jordi; Herranz-Diez, Carolina; Shaffer, J.E. [et al.]. Mechanical and microstructural characterization of new nickel-free low modulus beta-type titanium wires during thermomechanical treatments. Materials Science and Engineering: A, 2015, 636, p. 507-515. Disponible en: <https://www.sciencedirect.com/science/article/abs/pii/S0921509315003020?via%3Dihub>. Fecha de acceso: 11 may. 2020. DOI: 10.1016/j.msea.2015.03.060.
This item appears in the following Collection(s)
- Ciències de la Salut [745]
Rights
© 2015 Elsevier B.V. All rights reserved.