High strength, low stiffness, porous NiTi with superelastic properties

被引：212

作者：

Greiner, C ^{[1
]}

Oppenheimer, SM ^{[1
]}

Dunand, DC ^{[1
]}

机构：

[1] Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA

来源：

ACTA BIOMATERIALIA | 2005年 / 1卷 / 06期

基金：

美国国家科学基金会;

关键词：

nickel; titanium; nitinol; foams; superelasticity; bone replacement;

D O I：

10.1016/j.actbio.2005.07.005

中图分类号：

R318 [生物医学工程];

学科分类号：

0831 ;

摘要：

Near-stoichiometric NiTi with up to 18% closed porosity was produced by expansion at 1200 degrees C of argon-filled pores trapped by powder metallurgy within a NiTi billet. When optimally heat-treated, NiTi with 6-16% porosity exhibits superelasticity, with recoverable compressive strains up to 6% at a maximum compressive stress up to 1700 MPa. The apparent Young's modulus of NiTi with 16% porosity, measured during uniaxial compression, is in the range of 15-25 GPa (similar to human bone), but is much lower than measured ultrasonically (similar to 40 GPa), or predicted from continuum elastic mechanics. This effect is attributed to the reversible stress-induced transformation contributing to the linear elastic deformation of porous NiTi. The unique combination of low stiffness, high strength, high recoverable strains and large energy absorption of porous superelastic NiTi, together with the known biocompatibility of NiTi, makes this material attractive for bone-implant applications. (c) 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

引用

页码：705 / 716

页数：12

共 49 条

[1] Porous NiTi by thermal explosion mode of SHS: processing, mechanism and generation of single phase microstructure [J].