Simplified shape memory alloy (SMA) material model for vibration isolation

2001 ◽  
Author(s):  
Dimitris C. Lagoudas ◽  
John J. Mayes ◽  
Mughees M. Khan
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Vibration Isolation ◽  
Material Model

The Concept of Physical Metric in the Thermomechanical Modeling of Phase Transformations With Emphasis on Shape Memory Alloy Materials

2013 ◽  
Vol 135 (2) ◽  
Author(s):  
Vassilis P. Panoskaltsis ◽  
Lazaros C. Polymenakos ◽  
Dimitris Soldatos
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Phase Transformations ◽  
Shape Memory Effect ◽  
Memory Effect ◽  
Material Model ◽  
Internal Variable ◽  
Theoretical Interest ◽  
Numerical Examples ◽  
Thermomechanical Modeling

In this work we derive a new version of generalized plasticity, suitable to describe phase transformations. In particular, we present a general multi surface formulation of the theory which is capable of describing the multiple and interacting loading mechanisms, which occur during phase transformations. The formulation relies crucially on the consideration of the intrinsic material (“physical”) metric as a primary internal variable and does not invoke any decomposition of the kinematical quantities into elastic and inelastic (transformation induced) parts. The new theory, besides its theoretical interest, is also important for application purposes such as the description and the prediction of the response of shape memory alloy materials. This is shown in the simplest possible setting by the introduction of a material model. The ability of the model in simulating several patterns of the experimentally observed behavior of these materials such as the pseudoelastic phenomenon and the shape memory effect is assessed by representative numerical examples.

scholarly journals Tests on Pretrained Superelastic NiTi Shape Memory Alloy Rods: Towards Application in Self-Centering Link Beams

2018 ◽  
Vol 2018 ◽  
pp. 1-13
Author(s):  
Xian Xu ◽  
Guangming Cheng ◽  
Junhua Zheng
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Strain Amplitude ◽  
Loading Rate ◽  
Mechanical Performance ◽  
Material Model ◽  
Niti Shape Memory Alloy ◽  
Test Results ◽  
Potential Applications ◽  
Strain Model

Austenitic shape memory alloy has potential applications in self-centering seismic resistant structural systems due to its superelastic response under cyclic tension. Raw austenitic SMA needs proper pretreatments and pretraining to gain a stable superelastic property. In this paper, tests are carried out to investigate the effects of pretraining, pretreatments, loading rate, and strain amplitude on the mechanical performance on austenitic SMA rods with a given size. The tested rods are to be used in a new concept self-centering steel link beam. Customized pretraining scheme and heat treatment are determined through the tests. The effects of loading rate and strain amplitude are investigated. A simplified stress-strain model for the SMA rods oriented to numerical simulations is obtained based on the test results. An example of using the simplified material model in numerical analysis of a self-centering steel link beam is conducted to validate the applicability of the model.

scholarly journals Dynamic Characteristics of Hanging Truss Having Shape Memory Alloy Wires

2017 ◽  
Vol 7 (2) ◽  
pp. 6 ◽  
Author(s):  
Xuan Zhang ◽  
Kazuyuki Hanahara ◽  
Yukio Tada
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Dynamic Characteristics ◽  
Dynamic Problem ◽  
Vibration Isolation ◽  
Mechanical Characteristics ◽  
Structural System ◽  
Vibration Attenuation ◽  
Calculation Process ◽  
Absorption Characteristics

In this study, we discuss the dynamics of a type of hanging truss structural system consisting of rigid and wire members, part of which are SMA (shape memory alloy) wires. This kind of truss structure has the capability of vibration isolation and absorption. Characteristics of zero compressive stiffness of wire members, SMA wire members and hanging configuration of the structure itself contribute to the effect of vibration isolation. The hysteretic loop of SMA wires plays a significant role in vibration attenuation. Mathematical models for this kind of dynamic problem are developed. Calculation process is introduced to take into account the mechanical characteristics of SMA and wire members. Dynamic characteristics are discussed; simultaneously, the effects of vibration isolation and attenuation have been confirmed. On the basis of the numerical calculations, advantages of combinations of various types of wire members, including the truss units having no bracing wires have been demonstrated. 

Damping capacity in pseudo-elastic and ferro-elastic shape memory alloy-reinforced hybrid composite beam

2019 ◽  
Vol 38 (10) ◽  
pp. 467-477 ◽  
Author(s):  
Yahya Bayat ◽  
Hamid EkhteraeiToussi
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Composite Beam ◽  
Volume Fraction ◽  
Hysteresis Loops ◽  
Beam Theory ◽  
Material Model ◽  
Resonance Phenomenon ◽  
Damping Capacity ◽  
Concentrated Load

Reinforcing a composite beam with shape memory alloy wires may have several benefits such as reduction of buckling risks or elimination of unwanted oscillations. In this paper, the vibration damping of a typical shape memory alloy-reinforced composite or hybrid beam is explored. To formulate the thermo-mechanical behavior of embedded shape memory alloy wires, three-dimensional Panico–Brinson model is employed and tailored to one-dimensional model. This material model can simulate pseudo-elastic and ferro-elastic forms of martensite transformations which occurs in cyclic loadings. Besides, unlike the former studies which rely on classical beam theories, the first-order shear deformation beam theory is used to obtain more accurate estimations of shape memory alloy-wire hysteresis loops and their decaying characteristics. In order to explore the effects of a transient concentrated load applied in the middle of a beam, the governing equations are developed and discretized by differential quadrature–integral quadrature combined method. Incremental time marching solution of the problem is accomplished using the Newmark technique. Results are assessed by comparing with available literature. Considering different types of boundary conditions, the influence of pseudo-elastic and ferro-elastic hysteresis loops on the material damping effects, shape memory alloy volume fraction, and resonance phenomenon is studied in detail.

Hot Deformation Behavior of TiNiFe Shape Memory Alloy: A Study with Processing Map

2013 ◽  
Vol 631-632 ◽  
pp. 371-376 ◽  
Author(s):  
X.Q. Yin ◽  
S.J. Wang ◽  
Y.F. Li ◽  
B.D. Gao ◽  
X.Y. Kang ◽  
...  
Keyword(s):  
Shape Memory Alloy ◽  
Strain Rate ◽  
Shape Memory ◽  
Deformation Temperature ◽  
Processing Map ◽  
Material Model ◽  
Dynamic Material Model ◽  
Back Scattering ◽  
Instability Regions ◽  
Gleeble 3500

Isothermal compression of the TiNiFe shape memory alloy has been carried out on a Gleeble-3500 thermal simulation machine at the deformation temperature ranging from 1023K to 1323K, the strain rate ranging from 0.01s-1 to 10s-1 with total strain of 0.8. On the basis of dynamic material model, the processing map is established with two instability regions and a desirable domain which demonstrate optimum hot working conditions within the experimental parameters. By means of Electron Back Scattering Diffraction, we come to the conclusion that both dynamic recovery and dynamic recrystallization exist in the desirable domain with deformation temperature ranging 1123 K and strain rate 0.1s-1. The uneven deformation exits in the low deformation temperature with high strain rate area, such as 1023 K and10 s-1. And with 1323K and 0.01s-1 strain rate, the recrystallized grains are abnormal grow up.

Target shape optimization of functionally graded shape memory alloy compliant mechanisms

2017 ◽  
Vol 30 (9) ◽  
pp. 1385-1396
Author(s):  
Jovana Jovanova ◽  
Mary Frecker ◽  
Reginald F Hamilton ◽  
Todd A Palmer
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Modulus Of Elasticity ◽  
Compliant Mechanisms ◽  
Material Model ◽  
Functionally Graded ◽  
Beam Model ◽  
Shape Error ◽  
Target Shape ◽  
Trade Offs

This article focuses on the design optimization of shape memory alloy compliant mechanisms with functionally graded properties to achieve a user-defined target shape. The functional grading is approximated by allowing the geometry and the modulus of elasticity of each zone to vary. The superelastic phenomenon has been taken into account using a standard nonlinear shape memory alloy material model with linear region of higher modulus of elasticity and a superelastic region with much lower modulus of elasticity. A large deflection beam model is integrated with a multi-objective evolutionary algorithm for constrained optimization of the structure’s mechanical properties and geometry. Examples illustrate the trade-offs between the objectives of minimizing shape error, maximum stress, and volume. It is observed that in the optimized designs, the elastic modulus and the geometry work together in regions where large flexibility is required to achieve the target shape.

scholarly journals Nonlinear dynamic response of a Negative Stiffness-Shape Memory Alloy isolation system

2021 ◽  
Author(s):  
Andrea Salvatore ◽  
Biagio Carboni ◽  
Walter Lacarbonara
Keyword(s):  
Shape Memory Alloy ◽  
Dynamic Response ◽  
Shape Memory ◽  
Nonlinear Dynamic ◽  
Vibration Isolation ◽  
Extensive Study ◽  
Negative Stiffness ◽  
Response Curves ◽  
Nonlinear Dynamic Response ◽  
Isolation System

Abstract The negative stiffness exhibited by bi-stable mechanisms together with tunable hysteresis in the context of vibration isolation devices can enhance the dynamic resilience of a structure. The effects of negative stiffness and shape memory alloy (SMA) damping in base-isolated structures are here explored by carrying out an extensive study of the nonlinear dynamic response via pathfollowing, bifurcation analysis, and time integration. The frequency-response curves of the isolated structure, with and without the negative stiffness contribution, are numerically obtained for different excitation amplitudes to construct the acceleration and displacement transmissibility curves. The advantages of negative stiffness, damping augmentation and reduced accelerations and displacements transmissibility, as well as the existence of rich bifurcation scenarios giving rise to quasi-periodicity and synchronization, are extensively illustrated.

Optimal design of a hanging truss with shape memory alloy wires

2020 ◽  
Vol 44 (1) ◽  
pp. 95-107
Author(s):  
Xuan Zhang ◽  
Kazuyuki Hanahara ◽  
Yukio Tada ◽  
Zhiyong Pei ◽  
Zhe Li ◽  
...  
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Vibration Amplitude ◽  
Vibration Isolation ◽  
Point Of View ◽  
Optimal Solutions ◽  
Sectional Area ◽  
Structural System ◽  
Column Type ◽  
Transmission Reduction

In this study, we discuss the dynamic problem of a column-type hanging truss structural system with pseudo-elastic shape memory alloy (SMA) bracing wires. In the case where the sectional area values of the bracing SMA wire members are small enough to be negligible, it is close to the situation where there are no braces. In the case where the sectional area values of the bracing SMA wire members are large enough not to be negligible, the vibration amplitude of the peripheral end apparatus is suppressed from the deformation point of view. In addition, energy attenuation efficiency is improved with larger sectional area values because of the hysteretic characteristic of SMA. Small sectional area values of the bracing SMA wire members near the support ceiling or peripheral end are beneficial to vibration transmission reduction. These findings indicate that the placement and sectional area values of SMA wire members are both significant from the viewpoint of suppression of influence of the support ceiling vibration of the hanging truss. In this study, we obtain the optimal sectional area values of the SMA wire bracing members for the objectives of vibration isolation and attenuation. We discuss influences of different vibration conditions on the optimal solutions.

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