Constitutive model of shape memory alloys for unidirectional loading considering inner hysteresis loops

Abstract

A specimen-based macroscopic constitutive model of shape memory alloys for unidirectional loading, which is simple yet accurate and has a physical background, was derived from a grain-based microscopic model. To consider the inner hysteresis loops of a stress–strain–temperature relationship, a new inner loop model called the shift and skip model was proposed. This model is based on microscopic aspects and includes the memory effect of deformation history. Stress–strain relationships were simulated for some representative strain cycles. Numerical results showed that the proposed simple model could capture corresponding experimental results accurately enough to be applied for smart structural design. Comparison with major specimen-based macroscopic models was also discussed, under a unifying approach based on the driving energy and required transformation energy pair.

Zero-electric-power position retaining utilizing hysteresis on an antagonistic shape memory alloy system

“…SMA アクチュエータを駆動し飛行機の翼などの構造物を変形させる場合，その変形形状を維持するためには， 電力を供給し続けなければならない．電力の供給量を減らすために，SMA の応力-ひずみ-温度関係に表れるヒ ステリスを利用した無電力位置保持法を提案し，その概念を拮抗 SMA システムへ応用し，実験によりその可能 性を実証した．また，Ikeda ら (Ikeda et al, 2004;Ikeda, 2005Ikeda, , 2006Ikeda, , 2008 …”

“…Accordingly, it is seen that there is a possibility for the linear slider to retain any position with zero-energy supply. Ikeda et al, 2004;Ikeda, 2005Ikeda, , 2006Ikeda, , 2008 Ikeda et al, 2004;Ikeda, 2005Ikeda, , 2006Ikeda, , 2008 (c), it is seen that the proposed model can duplicate deformation behavior of the antagonistic SMA wires when a rectangular pulsed voltage is applied to the two wires alternatively. The deformation behavior of the antagonistic SMA wires can be explained using these figures.…”

Seismic response of steel braced frames with shape memory alloy braces

“…In addition for the load patterns shown in Figs. 8 and 9, the responses of the superelastic model were compared with experimental data [37] and a verified model [38], as can be seen in Figs. 10 and 11, respectively.…”

Application of SMA Composites in the Collectors of the Railway Pantograph for the Italian High-Speed Train

“…State-of-the-art modeling of SMA focuses on the evolution of austenite-martensite transformation, through thermomechanical model (see, for instance, Ref 7,8), for strain values of the order of 1%‚5%, including strain-rate dependence for low frequency. As mentioned earlier, in the present application lower strain amplitudes are induced, and the intrinsic damping of the martensite due to twin boundary movement is exploited.…”