A novel metastable β-type Zr-12Nb-4Sn alloy with low Young's modulus and low magnetic susceptibility

In this study, a novel metastable beta-type Zr-12Nb-4Sn alloy was designed and fabricated for hard tissue replacements. Upon solution treatment followed by water-quenching, the beta-type Zr-12Nb-4Sn alloy possesses a combination of low Young's modulus (44 GPa) and low magnetic susceptibility (1.42 x 10(-6) cm(3) g(-1)). An analysis of single-crystal elastic constants and Hill approximation shows that compared with binary beta-type Ti-based alloys, the present beta-type Zr-12Nb-4Sn alloy exhibits lower bcc-structural (beta-phase) stability represented by its slightly lower C' and much lower C-44, which gives rise to the ultralow Young's modulus in Zr-12Nb-4Sn alloy. Meanwhile, the low magnetic susceptibility of raw materials, i.e., Zr (1.32 x 10(-6) cm(3) g(-1)), Nb (2.24 x 10(-6) cm(3) g(-1)) and Sn (0.03 x 10(-6) cm(3) g(-1)), leads to the eventual low magnetic susceptibility of Zr-12Nb-4Sn alloy. These results might shed some light on design and development of novel beta-type Zr alloys, with a combination of lower Young's modulus and lower magnetic susceptibility, for biomedical applications. (C) 2018 Elsevier B.V. All rights reserved.