Hysteretic Dynamics of Ferroelectric Materials Under Electro-Mechanical Loadings

Smart Materials, Adaptive Structures and Intelligent Systems, Volume 1 ◽

10.1115/smasis2008-333 ◽

2008 ◽

Cited By ~ 3

Author(s):

Linxiang Wang

Keyword(s):

Electric Field ◽

Phase Transformations ◽

Landau Theory ◽

Hysteresis Loops ◽

Ferroelectric Materials ◽

Differential Model ◽

Mechanical Coupling ◽

First Order ◽

Bias Stress ◽

First Order Phase

In the current paper, the hysteretic dynamics of ferroelectric materials under combined electro-mechanical loadings is investigated using a macroscopic differential model. The model is constructed on the basis of the Landau theory of the first order phase transformations. Hysteresis loops in the electric field and the butterfly-shaped behaviors in the electro-mechanical coupling are modeled as a consequence of polarizations and orientation switchings, together with nonlinear electro-mechanical coupling effects. The effects of bias stress on the orientation switchings are investigated numerically. Comparison of the model results with its experimental counterparts is presented, capability of the model is approved.

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Macroscopic Differential Model for Hysteresis and Butterfly-Shaped Behavior in Ferroelectric Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.47-50.65 ◽

2008 ◽

Vol 47-50 ◽

pp. 65-68 ◽

Cited By ~ 4

Author(s):

Lin Xiang Wang ◽

Ying Chen ◽

Wen Li Zhao

Keyword(s):

Landau Theory ◽

Hysteresis Loops ◽

Ferroelectric Materials ◽

Free Energy Function ◽

System State ◽

Differential Model ◽

First Order ◽

State Switching ◽

Transformation Hysteresis ◽

First Order Phase

In the current paper, a macroscopic differential model is constructed on the basis of the Landau theory of the first order phase transformation. Hysteresis loops and butterfly-shaped behaviors are modeled as a consequence of polarizations and orientation switchings. A non-convex free energy function is constructed to characterize different polarization orientations in the materials. Polarizations and orientation switchings are modeled by formulating the system state switching from one equilibrium state to another, as differential equations. The hysteresis loops and butterfly-shaped behaviors are successfully modeled. Comparison of the model results with the experimental counterpart is also presented.

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Feedback Linearization of Hysteretic Thermoelastic Dynamics of Shape Memory Alloy Actuators with Phase Transformations

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.47-50.69 ◽

2008 ◽

Vol 47-50 ◽

pp. 69-72 ◽

Cited By ~ 2

Author(s):

Lin Xiang Wang ◽

Rong Liu ◽

Roderick Melnik

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Feedback Linearization ◽

Landau Theory ◽

Nonlinear Feedback ◽

Differential Model ◽

Mechanical Coupling ◽

First Order ◽

First Order Phase ◽

Material Temperature

In the current paper, a macroscopic differential model for the hysteretic dynamics in shape memory alloy actuators is constructed by using the modified Landau theory of the first order phase transformation. An intrinsic thermo-mechanical coupling is achieved by constructing the free energy as a function depends on both mechanical deformation and the material temperature. Both shape memory and pseudoelastic effects are modeled. The hysteretic dynamics is linearized by introducing another hysteresis loop via nonlinear feedback strategy, which cancels the original one.

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