Two-step strain glass transition in NiTi shape memory alloy with unique properties

Figures & data

Figure 1. DSC and in-situ cooling XRD analysis. (a) DSC heat flow curves upon cooling of the CR and A_473K∼A_873K samples. (b) Cooling and heating heat flow loop of the A_473K sample. (c) In-situ cooling XRD profiles of the A_473K sample.

Figure 2. Resistivity and DMA measurements of the A_473K sample. (a) Resistivity measurements. T_nd refer to onset temperatures the R-like precursor. (b) DMA analysis of the 473 K annealed sample. (c–d) Fitting of the Vogel–Fulcher relation for two frequency-dependent dips.

Figure 3. Phase diagram involving various transition pathways and corresponding tunable superelastic properties.

Figure 4. Comparisons of the superelasticity under different transition pathways with various superelastic materials. (a–c) The strength, recoverable strain, and Young’s modulus under different transition pathways. (d) Comparison of the recoverable strain and Young’s modulus with various superelastic materials, including the NiTi-based SMA [38,39], NiTi-Nb composite [40], Cu₆₉Al₁₇Mn₁₄ single crystal [41], Cu-based SMA [42,43], Mg-based SMA [44], Ti-based SMA [45,46], Fe-based SMA [47], TiNiFe composite [24], and Co₂₅Ni₂₅(HfTiZr)₅₀ high-entropy alloy [48].

Figure 5. TEM observation upon cooling and the associated wide-temperature superelasticity of TSGT. (a, d) TEM-SAD patterns at 290 and 240 K. The intensity profiles of the insets are plotted along the red dashed line. (b, e) HR-TEM images at 290 and 240 K. (c, f) IFFT images corresponding to HR-TEM observations. (g) Wide-temperature superelasticity measurements. (h–j) Recoverable strain, hysteresis, and Young’s modulus in relation to testing temperature.

Otsuka K, Ren X. Physical metallurgy of Ti–Ni-based shape memory alloys. Prog Mater Sci. 2005;50(5):511–678. doi:10.1016/j.pmatsci.2004.10.001

 Web of Science ®Google Scholar

Tan SM, Miyazaki S. Ti-content dependence of transformation pseudoelastivity characteristics of TixNi(92−x)Cu8 shape memory alloys. Mater Sci Eng A. 1997;237(1):79–86. doi:10.1016/S0921-5093(97)00119-6

 Web of Science ®Google Scholar

Hao S, Cui L, Jiang D, et al. A transforming metal nanocomposite with large elastic strain, low modulus, and high strength. Science. 2013;339(6124):1191–1194. doi:10.1126/science.1228602

 PubMed Web of Science ®Google Scholar

Xu S, Odaira T, Sato S, et al. Non-Hookean large elastic deformation in bulk crystalline metals. Nat Commun. 2022;13(1):5307. doi:10.1038/s41467-022-32930-9

 PubMed Web of Science ®Google Scholar

Sutou Y, Omori T, Kainuma R, et al. Grain size dependence of pseudoelasticity in polycrystalline Cu–Al–Mn-based shape memory sheets. Acta Mater. 2013;61(10):3842–3850. doi:10.1016/j.actamat.2013.03.022

 Web of Science ®Google Scholar

Sutou Y, Omori T, Kainuma R, et al. Ductile Cu–Al–Mn based shape memory alloys: general properties and applications. Mater Sci Technol. 2008;24(8):896–901. doi:10.1179/174328408X302567

 Web of Science ®Google Scholar

Ogawa Y, Ando D, Sutou Y, et al. A lightweight shape-memory magnesium alloy. Science. 2016;353(6297):368–370. doi:10.1126/science.aaf6524

 PubMed Web of Science ®Google Scholar

Hao Y, Li S, Prima F, et al. Controlling reversible martensitic transformation in titanium alloys with high strength and low elastic modulus. Scr Mater. 2012;67(5):487–490. doi:10.1016/j.scriptamat.2012.06.011

 Web of Science ®Google Scholar

Hao YL, Li SJ, Sun SY, et al. Elastic deformation behaviour of Ti–24Nb–4Zr–7.9Sn for biomedical applications. Acta Biomater. 2007;3(2):277–286. doi:10.1016/j.actbio.2006.11.002

 PubMed Web of Science ®Google Scholar

Tanaka Y, Himuro Y, Kainuma R, et al. Ferrous polycrystalline shape-memory alloy showing huge superelasticity. Science. 2010;327(5972):1488–1490. doi:10.1126/science.1183169

 PubMed Web of Science ®Google Scholar

Zhang J, Liu Y, Yang H, et al. Achieving 5.9% elastic strain in kilograms of metallic glasses: nanoscopic strain engineering goes macro. Mater Today. 2020;37:18–26. doi:10.1016/j.mattod.2020.02.020

 Web of Science ®Google Scholar

He QF, Wang JG, Chen HA, et al. A highly distorted ultraelastic chemically complex Elinvar alloy. Nature. 2022;602(7896):251–257. doi:10.1038/s41586-021-04309-1

 PubMed Web of Science ®Google Scholar