Piezoelectric Materials - Christopher R Bowen

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Résumé :

Preface xi

Acknowledgements xiii

1 Introduction 1

1.1 Active and Sensory Materials for Smart Systems 1

1.2 Energy Harvesting Materials 3

1.3 Multifunctional Materials, Devices, Systems and Structures 3

1.4 Piezoelectric, Pyroelectric and Ferroelectric Materials 4

References 5

2 Piezoelectric Fundamentals 7

2.1 Piezoelectric Materials 7

2.2 Ferroelectric Materials 10

2.2.1 Non-centrosymmetric Unit Cells 10

2.2.2 Lead Zirconate Titanate (Pb(ZrXTi1?x)O3 , Pzt) Ferroelectrics 13

2.2.3 Ferroelectric Domains 14

2.2.4 Poling of Ferroelectric Materials 16

2.3 Pyroelectric Materials 18

2.4 Piezoelectric Forms: Bulk, Thin Films and Fibre Composites 19

2.4.1 Piezoelectric Composites and Connectivity 19

2.4.2 Active Fibre Composites and Macro-Fibre Composites 20

2.5 Concluding Remarks 22

References 23

3 Properties of Piezoelectric Materials 27

3.1 Introduction 27

3.2 Constitutive Equations 28

3.2.1 Alternative Single-Axis Formulations 28

3.2.2 Multi-Axis Linear Model 30

3.2.2.1 Example Piezoelectric Element 32

3.2.3 Coupling Coefficients 34

3.3 Polarisation-Electric Field Response of a Ferroelectric 36

3.4 Strain-Field Response of a Ferroelectric 39

3.5 Material Properties and Selection of Materials 41

3.5.1 Barium Titanate (BaTiO3) 41

3.5.2 Lead Zirconate Titanate (PZT, Pb(Zr,Ti)O3) 42

3.5.3 Ferroelectric Polymers 48

3.6 Mechanical Depolarisation of Ferroelectric Materials 48

3.7 Creep of Ferroelectric Materials 52

3.8 Strain Limits of Piezoelectric Actuators (Expansion) 54

3.9 Strain Limits of Piezoelectric Actuators (Contraction) 55

3.10 Resonance Behaviour of Piezoelectric Materials and Ceramic Structures 55

3.11 Ageing of Ferroelectrics 57

3.12 Temperature Limits and Self-Heating 58

3.13 Cyclic Operation - Frequency Effects 58

3.13.1 Self-Heating Due to Ferroelectric Hysteresis 59

3.13.2 Current Requirements During Frequency Cycling 60

3.14 Thermal Expansion Coefficient 61

3.15 Summary 62

References 62

4 Piezoelectric Actuators 65

4.1 Introduction 65

4.2 Free Displacement and Blocking Force 65

4.3 Single-Layer Actuator 67

4.4 Stack Actuators 71

4.4.1 Actuator Preloading 72

4.4.2 Piezoelectric Stack Actuator Selection Example 73

4.4.3 Optimum Stack Dimensions 76

4.4.4 Piezoelectric Actuator Stack Sizing Guidelines 77

4.5 Rectangular Bending Actuators (Bimorphs) 79

4.5.1 Bimorph Characteristics 79

4.5.2 Other Rectangular Benders 83

4.6 Ring Benders 84

4.6.1 Ring Bender Deformation Analysis 84

4.6.2 Ring Bender Free Displacement and Blocking Force 92

4.6.3 Other Circular Benders 95

4.7 Mechanical Amplification 95

4.8 Complex Actuator Design 97

4.8.1 Motion Accumulation 97

4.8.2 Ultrasonic Motors 98

4.9 Concluding Remarks 99

References 100

5 Sensors 101

5.1 Introduction 101

5.2 Piezoelectric Accelerometers 101

5.2.1 Accelerometer Modes of Operation (Compressive, Shear and Flexural d33 and d15) 105

5.2.2 Material Selection for Accelerometers 106

5.3 Force and Pressure Sensors 110

5.3.1 High-Frequency Capability 111

5.3.2 Sensor Sensitivity 111

5.4 Temperature and Thermal Effects 113

5.5 Hydrophones 115

5.5.1 Background to Hydrostatic Coefficients 115

5.5.2 Derivation of Performance Indicators for Hydrophone Materials 116

5.5.3 Hydrophone Constructio...

Biographie:

Christopher R. Bowen University of Bath, UK

Andrew R. Plummer University of Bath, UK

Series Editors

Arthur Willoughby University of Southampton, Southampton, UK

Peter Capper formerly of SELEX Galileo Infrared Ltd, Southampton, UK

Safa Kasap University of Saskatchewan, Saskatoon, Canada...

Sommaire:

Authoritative reference making piezoelectric materials technology more accessible by crossing the boundary between fundamental materials physics and applied engineering

Piezoelectric Materials provides a comprehensive overview of the subject, an important class of smart materials which are useful as both actuators and sensors, covering materials, properties, and devices, including case studies of example applications. In addition to providing the underlying science on the subject, the text also supports those interested in using piezoelectric actuators and sensors in real world applications. Early chapters help the reader understand the limits and appropriate operating conditions for the piezoelectric and ferroelectric devices described in later chapters.

Other topics discussed in Piezoelectric Materials include:

• The range of piezoelectric and ferroelectric materials and their fundamental properties and applications in sensors, actuators, and as energy harvesting elements.
• Designs for various piezoelectric devices, including case studies on piezoelectric actuator applications, e.g., for servovalves, hydrophones, and active vibration control.
• Key limits of these materials and fundamental equations to predict displacement, force, resonance, and power requirements.

Piezoelectric Materials serves as an invaluable reference on the subject and makes piezoceramic materials technology more accessible to researchers, advanced students, and practicing engineers. The text is also helpful to those in industries using piezoelectrics, in particular manufacturers of optics, photonics, and nanometrology equipment....