Shape Memory Alloys Wires: From Small to Medium Diameter

Abstract:

The use of Shape Memory Alloys in dampers devices able to reduce the wind, rain or traffic induced oscillations in stayed cables is well represented in the literature. An analysis realized on standard cables at existing facilities shows the reliable efficiency of the SMA wire in damping oscillations. Such studies also provide tools to build the SMA dampers and to account for the effects of the external temperature in the SMA. The particular study reported in this paper focuses on a critical discussion on the relation between the wire diameter and macroscopic behavior and external temperature effects. The damping requires the absorption of the mechanical energy and its conversion to heat via the action of hysteresis cycles. The study was realized on wires of different diameters. In particular, the study centers on wires of diameter 0.2, 0.5 and 2.46 mm. The flat cycles showed by the thin wires (i.e., diameter 0.2 and 0.5 mm) and the non-classical S-shaped cycles of wires of diameter 2.46 mm establish clear differences of the response under external summer-winter temperature actions. Depending of the room temperature and SMA composition, a complete flat transformation in thin wires requires stresses, in general, near 300-400 MPa. A complete transformation for an S-shaped cycle need stresses as higher as 600 MPa. The analysis of the behavior of these wires under the action of warm temperatures in summer and cold temperatures in winter, suggests that thin wires lose their pseudo-elastic state in winter. The S-shaped permits positive working in extended temperature domain and a supplementary investigation establishes that S-shaped can be increased by strain aging. The hysteretic behavior in S-shaped permits practical working under external temperatures as applications in bridges require. From a fundamental point of view, the flat cycles are coherent with the classical treatment of the SMA as a first order phase transition but the S-shaped can be considered associated to an anomaly in heat capacity.

• Periodical: Advances in Science and Technology (Volume 101)
• Pages: 79-88
• DOI: https://doi.org/10.4028/www.scientific.net/AST.101.79
• Online since: October 2016
• Authors: Vicenç Torra*, Sara Casciati, Michele Vece
• Keywords: Application to Civil Engineering, Damping, Intrinsic Effects, Shape Memory Alloys

References

[1] P. Ehrenfest, Phase changes in the ordinary and extended sense classified according to the corresponding singularities of the thermodynamic potential, Proceedings of Acad Sci Amsterdam, 36 (1933) 153-157.

[2] L.D. Landau, Zur Theorie der phasenumwandlungen II. Phys Z Sowjetunion. 11 (1937) 26-35.

[3] F.C. Lovey, V. Torra, Shape memory in Cu-based alloys: phenomenological behavior at the mesoscale level and interaction of martensitic transformation with structural defects in Cu-Zn-Al, Prog Mater Sci. 44-3 (1999) 189-289.

DOI: 10.1016/s0079-6425(99)00004-3

[4] V. Torra, A. Isalgue, FC Lovey, M Sade, M. Shape memory alloys as an effective tool to damp oscillations. Study of the fundamental parameters required to guarantee technological applications, J Therm Anal Cal. 119-3 (2015) 1475-1533.

DOI: 10.1007/s10973-015-4405-7

[5] K. Otsuka, C.M. Wayman Eds, Shape Memory Materials, Cambridge: Cambridge University Press, (1998).

[6] C.M. Wayman, Shape memory and related phenomena, Prog Mater Sci. 36(1992) 203-224.

[7] K. Otsuka, X Ren. Physical metallurgy of Ti-Ni-based shape memory alloys, Prog Mater Sci. 50-5 (2005) 511-678.

DOI: 10.1016/j.pmatsci.2004.10.001

[8] H.E. Mohammad, H. Mandi, T. Majid, S.B. Bhaduri, Manufacturing and processing of NiTi implants: A review, Prog Mater Sci. 57-5 (2012) 911-946.

[9] A. Ishida, M. Sato, A. Takei, S. Miyazaki, Effect of heat treatment on shape memory behavior of Ti-rich Ti-Ni thin films, Mater T JIM. 36-11 (1995) 1349-1355.

DOI: 10.2320/matertrans1989.36.1349

[10] J.I. Kim, H.Y. Kim, H. Hosoda, S. Miyazaki, H. Satoru, Mechanical Properties and Shape Memory Behavior of Ti-Nb Alloys, Mater T JIM. 45-7 (2004) 2443-2448.

DOI: 10.2320/matertrans.45.2443

[11] J.I. Kim, H.Y. Kim, H. Hosoda, S. Miyazaki, Shape Memory Behavior of Ti–22Nb–(0. 5–2. 0)O (at%) Biomedical Alloys, Mater T JIM. 46-4 (2005) 852-857.

DOI: 10.2320/matertrans.46.852

[12] H. Kanetaka, H. Hosoda , Y. Shimizu, T. Kudo, Y. Zhang, M. Kano, Y. Sano, S. Miyazaki, In Vitro Biocompatibility of Ni-Free Ti-Based Shape Memory Alloys for Biomedical Applications, Mater T JIM. 51-10 (2010) 1944-(1950).

DOI: 10.2320/matertrans.m2010038

[13] H. Janocha, Ed. Adaptronics and smart structures, Berlin, Springer, (1999).

[14] M. Kohl, Microactuators, Berlin, Springer Verlag, (2004).

[15] J. Van Humbeeck, Non-medical applications of shape memory alloys, Mat Sci Eng A-Struct. 273-275 (1999) 134-148.

DOI: 10.1016/s0921-5093(99)00293-2

[16] V. Torra, C. Auguet, A. Isalgue, G. Carreras, P. Terriault, F.C. Lovey, Built in dampers for stayed cables in bridges via SMA, The SMARTeR-ESF project: A mesoscopic and macroscopic experimental analysis with numerical simulations, Eng Struct. 49 (2013).

DOI: 10.1016/j.engstruct.2012.11.011

[17] V. Torra, G. Carreras, S. Casciati, P. Terriault, On the NiTi wires in dampers for stayed cables, Smart Structure Systems, 13-3 (2014) 353-374.

DOI: 10.12989/sss.2014.13.3.353