Ultra-wide-temperature-range superelasticity and intrinsic two-way shape memory effect in Co-Ni-Ga microwires

• Main Authors: Chen, H. (Author), Cong, D. (Author), Lang, R. (Author), Li, R. (Author), Li, S. (Author), Meng, L. (Author), Niu, Y. (Author), Song, C. (Author), Wang, Y.-D (Author), Yin, T. (Author), Zhang, X. (Author)
• Format: Article
• Language: English
• Published: American Institute of Physics Inc. 2022
• Subjects: Cobalt alloys; Elasticity; Gallium alloys; Large strains; Mechanical training; Microwire; Shape memory effect; Single crystals; Super elastic behavior; Superelasticity; Temperature window; Tensile strain; Ternary alloys; Two-way shape memory effect; Ulitovsky method; Ultra-wide; Wide temperature ranges
• Online Access: View Fulltext in Publisher
• ISBN: 00036951 (ISSN)
• DOI: 10.1063/5.0089321

We demonstrate perfect superelasticity and inherent two-way shape memory effect in Co49Ni21Ga30 microwires fabricated by a Taylor-Ulitovsky method. With the formation of an almost complete [001]A-oriented single crystal along the axis of the wire, the as-drawn microwire displays great superelastic behaviors with a large reversible tensile strain of >8% over an ultra-wide temperature window of 550 K (223-773 K). Simultaneously, an excellent intrinsic two-way shape memory effect with a considerably large strain output (∼6.3%) was also obtained in this Co49Ni21Ga30 microwire. After mechanical training, the two-way shape memory strain can reach up to 6.8% at a low operating temperature. With the combination of above extraordinary functional properties and the low cost of fabrication, the Co49Ni21Ga30 microwire holds a significant potential for applications in miniature sensing and self-actuating devices in the future. © 2022 Author(s).