Piezoceramic Sensors/Actuators with Interdigitated Electrode Patterns

195 Pages·2014·23.64 MB·English

UCLA
UCLA Electronic Theses and Dissertations
Title
Piezoceramic Sensors/Actuators with Interdigitated Electrode Patterns
Permalink
https://escholarship.org/uc/item/0140h0bp
Author
Pisani, David McIntyre
Publication Date
2014

Peer reviewed|Thesis/dissertation
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University of California
University of California
Los Angeles
Piezoceramic Sensors/Actuators
with Interdigitated Electrode Patterns
A dissertation submitted in partial satisfaction
of the requirements for the degree
Doctor of Philosophy in Mechanical and Aerospace Engineering
by
David McIntyre Pisani
2014
© Copyright by
David McIntyre Pisani
2014
Abstract of the Dissertation
Piezoceramic Sensors/Actuators
with Interdigitated Electrode Patterns
by
David McIntyre Pisani
Doctor of Philosophy in Mechanical and Aerospace Engineering
University of California, Los Angeles, 2014
Professor Christopher S. Lynch, Chair
Monolithic piezoelectric ceramic devices are well understood and employed in a wide
variety of structural actuation and sensing applications. Over the last twenty years piezo-
ceramic fiber composites with interdigitated electrodes (IDE) have fallen into favor. These
piezocompositedeviceswithIDEhavebeenshowntobemoreconformal,durableandrespon-
sive than conventional monolithic devices. One of the more prevalent piezocomposite devices
with IDE is the Macro Fiber Composite (MFC) developed at the NASA-Langley Research
Center. The MFC shows superior free strain actuation performance, manufacturability and
reliability over conventional devices.
WhiletheMFCboastssomeimprovedcharacteristicsoverconventionaldevices, theuseof
IDE also introduces added complexity. Simple in design, the IDE causes nonuniform electric
fields, large electric field gradients and increased hysteresis in the device. Characterization
and modeling efforts of the MFC beyond a linear approximation have been limited. The
majority of published work relies on experimental quantification and a heavy reliance on
linear finite element analysis. The MFC has significant time dependent effects, conduction
issues, creep, and other nonlinear effects that have not been explored.
Thisstudyservesasanattempttorectifysomeofthepreviouslyoverlookedissuesofnon-
linearity in piezocomposite actuators with IDE. As a baseline of comparison, the capability
of a MFC to serve as a strain sensing/actuating rosette was compared to single crystal PMN-
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PT. It was found that increased hysteresis and creep caused the MFC to perform poorly by
comparison. This spurred the process of seeking improved IDE designs. A twenty actuator
study was performed using actuators with different electrode line widths and spacings. It
was found that the hysteresis of an actuator with IDE could be reduced, but with the
sacrifice of some of the free strain actuation. For accurate strain sensing/actuation, devices
with large electrode line widths were found to show less hysteresis. For maximal free strain
actuation, devices with small electrode line widths and large electrode spacing were found
to have larger free strain actuation. The free strain frequency response was explored for the
MFC, and custom devices were designed to mitigate some of the frequency dependence. The
IDE devices were characterized using a dielectric finite element model and using a nonlinear
ferroelectric finite element model. A phase field model was also developed to explore domain
formation along electrode edges.
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The dissertation of David McIntyre Pisani is approved.
Ertugrul Taciroglu
William S. Klug
Gregory P. Carman
Christopher S. Lynch, Committee Chair
University of California, Los Angeles
2014
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Table of Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1.1 History of IDE on Piezoceramic Fiber Composites . . . . . . . . . . . 2
1.1.2 Computational Modeling of Piezocomposites . . . . . . . . . . . . . . 7
1.1.3 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.2 Contributions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
1.3 Dissertation Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2 Piezocomposite Actuator Applications . . . . . . . . . . . . . . . . . . . . . 14
2.1 Piezoelectric Strain Rosettes . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2.1.1 Modeling Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.1.2 Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.1.3 Results, Comparison, and Discussion . . . . . . . . . . . . . . . . . . 21
2.2 Macro Fiber Composites as Sensors/Actuators . . . . . . . . . . . . . . . . . 25
2.2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
2.2.2 Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
2.2.3 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
2.2.4 Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
3 Polarization of Piezoceramics with IDE . . . . . . . . . . . . . . . . . . . . 37
3.1 Experimental Arrangement . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
3.1.1 Materials and Specimen Preparation . . . . . . . . . . . . . . . . . . 38
3.1.2 Experimental Procedure . . . . . . . . . . . . . . . . . . . . . . . . . 39
3.2 Experimental Results and Discussion . . . . . . . . . . . . . . . . . . . . . . 40
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3.3 Computational Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
3.3.1 Dielectric Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
3.3.2 Finite Element Formulation . . . . . . . . . . . . . . . . . . . . . . . 48
3.3.3 Mesh Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
3.4 Results and Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
3.5 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
4 Ferroelectric IDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
4.2 Experimental Arrangement . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
4.2.1 Materials and Specimen Preparation . . . . . . . . . . . . . . . . . . 61
4.2.2 Experimental Procedure . . . . . . . . . . . . . . . . . . . . . . . . . 64
4.3 Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
4.4 Computational Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
4.4.1 Linear FEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
4.4.2 Micromechanical Model . . . . . . . . . . . . . . . . . . . . . . . . . 75
4.4.3 Geometry and Boundary Conditions . . . . . . . . . . . . . . . . . . 77
4.5 Discussion and FEM Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . 78
4.5.1 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
4.5.2 FEM Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
4.6 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
5 Piezocomposite Actuator Frequency Dependency . . . . . . . . . . . . . . 91
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
5.2 Experimental Arrangement . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
5.2.1 Materials and Specimen Preparation . . . . . . . . . . . . . . . . . . 92
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5.2.2 Experimental Procedure . . . . . . . . . . . . . . . . . . . . . . . . . 95
5.3 Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
5.4 Experimental Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
5.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
6 IDE Composition Experiment . . . . . . . . . . . . . . . . . . . . . . . . . . 119
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
6.2 Experimental Arrangement . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
6.2.1 Materials and Specimen Preparation . . . . . . . . . . . . . . . . . . 120
6.2.2 Experimental Procedure . . . . . . . . . . . . . . . . . . . . . . . . . 122
6.3 Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
6.4 Experimental Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
6.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
7 Phase Field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
7.1 Phase Field Framework . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
7.1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
7.1.2 Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
7.1.3 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
8 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
8.1 Summary of Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
8.2 Contributions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154
8.3 Future Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
A Rosette Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
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B Finite Element Approximation . . . . . . . . . . . . . . . . . . . . . . . . . . 161
B.1 Global Derivatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
B.2 Volume Integrals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
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