Effects of Nb on the Microstructure and Compressive Properties of an As-Cast Ni44Ti44Nb12 Eutectic Alloy

Shifeng Liu; Song Han; Liqiang Wang; Jingbo Liu; Huiping Tang

doi:10.3390/ma12244118

Effects of Nb on the Microstructure and Compressive Properties of an As-Cast Ni₄₄Ti₄₄Nb₁₂ Eutectic Alloy

Materials (Basel). 2019 Dec 9;12(24):4118. doi: 10.3390/ma12244118.

Authors

Shifeng Liu¹, Song Han¹, Liqiang Wang², Jingbo Liu¹, Huiping Tang¹

Affiliations

¹ School of Metallurgical Engineering, Xi'an University of Architecture and Technology, No.13 Yanta Road, Xi'an 710055, China.
² State Key Laboratory of Metal Matrix Composites, School of Material Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240, China.

Abstract

The addition of Nb can form a eutectic phase with a NiTi matrix in a NiTi-based shape memory alloy, improving the transition hysteresis of the NiTi alloy. A Ni₄₄Ti₄₄Nb₁₂ ingot was prepared using the vacuum induction melting technique. Under compression deformation, the yield strength of the NiTi-Nb alloy is about 1000 MPa, the maximum compressive strength and strain can reach 3155 MPa and 43%, respectively. Ni₄₄Ti₄₄Nb₁₂ exhibited a superelastic recovery similar to that of the as-cast NiTi₅₀. Meanwhile, the loading-unloading cycle compression shows that the superelastic recovery strain reached a maximum value (2.32%) when the total strain was about 15%, and the superelasticity tends to rise first and then decrease as the strain increases.

Keywords: NiTi–Nb; compressive properties; eutectic phase; superelastic.