Optimal Control for Shape Memory Alloys of the One-Dimensional Frémond Model

A theoretical model for the crack monitoring of the shape memory alloy intelligent concrete is presented in this work. The mechanical properties of shape memory alloy materials are first given by the experimental test. The one-dimensional constitutive model of the shape memory alloys is reviewed by degenerating from a three-dimensional model, and the behaviors of the shape memory alloys under different working conditions are then discussed. By combining the electrical resistivity model and the one-dimensional shape memory alloy constitutive model, the crack monitoring model of the shape memory alloy intelligent concrete is given, and the relationships between the crack width of the concrete and the electrical resistance variation of the shape memory alloy materials for different crack monitoring processes of shape memory alloy intelligent concrete are finally presented. The numerical results of the present model are compared with the published experimental data to verify the correctness of the model.

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A micromechanics inspired constitutive model for shape-memory alloys: the one-dimensional case

Smart Materials and Structures ◽

10.1088/0964-1726/16/1/s06 ◽

2007 ◽

Vol 16 (1) ◽

pp. S51-S62 ◽

Cited By ~ 29

Author(s):

Amir Sadjadpour ◽

Kaushik Bhattacharya

Keyword(s):

Constitutive Model ◽

Shape Memory Alloys ◽

Shape Memory ◽

Dimensional Case ◽

One Dimensional ◽

The One

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Shape memory alloy–actuated prestressed composites with application to morphing automotive fender skirts

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x18812702 ◽

2018 ◽

Vol 30 (3) ◽

pp. 479-494 ◽

Cited By ~ 6

Author(s):

Venkata Siva C Chillara ◽

Leon M Headings ◽

Ryohei Tsuruta ◽

Eiji Itakura ◽

Umesh Gandhi ◽

...

Keyword(s):

Shape Memory Alloy ◽

Shape Memory Alloys ◽

Shape Memory ◽

Smart Materials ◽

Design Procedure ◽

Building Blocks ◽

Smart Composite ◽

Thermally Induced ◽

One Dimensional ◽

Flat Shape

This work presents smart laminated composites that enable morphing vehicle structures. Morphing panels can be effective for drag reduction, for example, adaptive fender skirts. Mechanical prestress provides tailored curvature in composites without the drawbacks of thermally induced residual stress. When driven by smart materials such as shape memory alloys, mechanically-prestressed composites can serve as building blocks for morphing structures. An analytical energy-based model is presented to calculate the curved shape of a composite as a function of force applied by an embedded actuator. Shape transition is modeled by providing the actuation force as an input to a one-dimensional thermomechanical constitutive model of a shape memory alloy wire. A design procedure, based on the analytical model, is presented for morphing fender skirts comprising radially configured smart composite elements. A half-scale fender skirt for a compact passenger car is designed, fabricated, and tested. The demonstrator has a domed unactuated shape and morphs to a flat shape when actuated using shape memory alloys. Rapid actuation is demonstrated by coupling shape memory alloys with integrated quick-release latches; the latches reduce actuation time by 95%. The demonstrator is 62% lighter than an equivalent dome-shaped steel fender skirt.

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Long-time behavior for the full one-dimensional Frémond model for shape memory alloys

Continuum Mechanics and Thermodynamics ◽

10.1007/s001610050146 ◽

2000 ◽

Vol 12 (6) ◽

pp. 423-433 ◽

Cited By ~ 5

Author(s):

Pierluigi Colli ◽

Philippe Laurençot ◽

Ulisse Stefanelli

Keyword(s):

Shape Memory Alloys ◽

Shape Memory ◽

Time Behavior ◽

Long Time Behavior ◽

One Dimensional ◽

Long Time

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Martensitic Transformation of High-Entropy and Medium-Entropy Shape Memory Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1016.1802 ◽

2021 ◽

Vol 1016 ◽

pp. 1802-1810

Author(s):

Hiromichi Matsuda ◽

Masayuki Shimojo ◽

Hideyuki Murakami ◽

Yoko Yamabe-Mitarai

Keyword(s):

Solid Solution ◽

High Temperature ◽

Martensitic Transformation ◽

Shape Memory Alloys ◽

Shape Memory ◽

Transformation Temperature ◽

Solid Solution Hardening ◽

Solution Hardening ◽

High Entropy ◽

The One

As new generation of high-temperature shape memory alloys, high-entropy alloys (HEAs) have been attracted for strong solid-solution hardened alloys due to their severe lattice distortion and sluggish diffusion. TiPd is the one potential high-temperature shape memory alloys because of its high martensitic transformation temperature above 500 °C. As constituent elements, Zr expected solid-solution hardening, Pt expected increase of transformation temperature, Au expected keeping transformation temperature, and Co expected not to form harmful phase. By changing the alloy composition slightly, two HEAs and two medium entropy alloys (MEAs) were prepared. Only two MEAs, Ti45Zr5Pd25Pt20Au5, and Ti45Zr5Pd25Pt20Co5 had the martensitic transformation. The perfect recovery was obtained in Ti45Zr5Pd25Pt20Co5 during the repeated thermal cyclic test, training, under 200 MPa. On the other hand, the small irrecoverable strain was remained in Ti45Zr5Pd25Pt20Au5 during the training under 150 MPa because of the small solid-solution hardening effect. It indicates that Ti45Zr5Pd25Pt20Co5 is the one possible HT-SMA working between 342 and 450 °C.

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