Piezoelectricity and ferroelectricity Applications of piezoelectric materials. Prof.Mgr.Jiří Erhart, Ph.D. Department of Physics FP TUL

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1 Piezoelectricity and ferroelectricity Applications of piezoelectric materials Prof.Mgr.Jiří Erhart, Ph.D. Department of Physics FP TUL

2 Piezoelectric effect Direct effect Converse effect Sensors static Charge generators Resonators Actuators Force Acceleration Pressure Ultrasound RF devices Resonant sensors Nonresonant Resonant US probes Sonochemistry Quartz watch Quartz resonators Gas, chemical detector Bending structures US motors FPM - Piezoelektřina 3

3 Piezoelectric gas ignitors Discharge between electrodes, charge is generated by piezoelectricity hammer impact on PZT ceramic element Piezo ceramics (inside) Electrodes Hammer FPM - Piezoelektřina 3 3

4 Quartz application Force, pressure and acceleration sensors (e.g. Kistler, Switzerland) FPM - Piezoelektřina 3 4

5 Accelerometer Deformation of piezoelectric element by the inertial force from the seismic mass FPM - Piezoelektřina 3 5

6 Quartz SiO natural or artificial crystal, quartz clock, e.g. wrist watch Warren Perry Mason ( ) Quartz crystal W.P.Mason: US patent No.,081,405 (1937) first patent on quartz clock resonator (fork resonator) FPM - Piezoelektřina 3 6

7 Quartz resonators W.G.Cady first frequency standard - US National Bureau of Standards, radio transmitter frequency stabilization Walter Guyton Cady ( ) FPM - Piezoelektřina 3 7

8 Ultrasound motor Ultrasound piezoelectric motors transversal travelling wave Shinsei motor FPM - Piezoelektřina 3 8

9 Ultrasound motor Ultrasound piezoelectric motor elliptic motion of stator surface friction with rotor Example: diameter 30mm FPM - Piezoelektřina 3 9

10 Langevin transducer Ultrasound motor rotor stator Paul Langevin ( ) PZT ceramics FPM - Piezoelektřina 3 10

11 Ultrasound motor - PILine Elliptic motion of the tip joined with PZT ceramics element FPM - Piezoelektřina 3 11

12 Ultrasound atomization of liquids Medicines application to mucous membrane in small droplets Air humidification Aerosol deposition onto textile materials etc. Droplet size is easily controllable by frequency It is in the range ofµm for frequency 1- MHz FPM - Piezoelektřina 3 1

13 Ultrasound atomization of liquids Liquid surface moves due to ultrasound wave Average droplet size F S r = ρ σ f r a m FP F T Narrow distribution of droplet size Production of atomized liquid amount is controllable Droplet size is controllable FPM - Piezoelektřina 3 13

14 Liquid atomizers Ultrasound humidifiers Drug inhalers FPM - Piezoelektřina 3 14

15 Electronic cigarette Atomiser inside cigarette US patent (007) FPM - Piezoelektřina 3 15

16 Ultrasound generation and application Medical diagnostics, healing Technology - welding, cleaning, NDT, sonochemistry, FPM - Piezoelektřina 3 16

17 Piezoelectric transformer - Rosen type US patent No.,830,74 (1958), C.A.Rosen et al. Piezoelectric transformer - Rosen type FPM - Piezoelektřina 3 17

18 Rosen type transformer Longitudinal plate vibration Common mechanical deformation IN OUT FPM - Piezoelektřina 3 18

19 Piezoelectric transformers commercial products Integrated with electronics CCFL electronics Rosen-type (Fuji & Co., Japan) Transoner (Face Electronics, USA) Multilayer (Noliac A/S, Denmark) FPM - Piezoelektřina 3 19

20 Rosen type PT IN OUT ceramics electrode polarization Radial poling - nonhomogeneous U E( r) = ln( r r 1 ) 1 r IN OUT ceramics electrode polarization FPM - Piezoelektřina 3 0

21 Rosen type PT Rectangular Rosen PT No. APC841 14mm/7mm/th.1mm Gain Efficiency Gain [-] Efficiency [%] Disc Rosen PT No. 1 APC841 diam. 0mm/th.0.8mm Gain Efficiency Load [Ω] Gain [-] Efficiency [%] Load [Ω] FPM - Piezoelektřina 3 1

22 Rosen type PT Rectangular Rosen PT APC 841, l = 14mm, w = 7mm, b = 1mm, V = 98mm 3 No-load parameters Z L, η 0 U U f r = khz ( ) 1 = Optimum load parameter Z L = 10kΩ U U f r = khz ( ) 3 1 OPT = η = 77% f r = khz OPT Peak power P IN = 56.5mW f r = khz P OUT = 43.6mW f r = khz Peak power density P IN /V = 0.58Wcm -3 P OUT /V = 0.44Wcm -3 Input and Output impedance Z IN = 167Ω f r = 11.9 khz Z IN = 9.kΩ f a = khz Z OUT = 1.68kΩ f r = khz Z OUT = 14.5MΩ f a = 13.4 khz Disc Rosen PT APC 841, r = 10mm, b = 0.8mm, V = 51mm 3 No-load parameters Z L, η 0 U U f r = 10.5 khz ( ) 19 1 = Optimum load parameter Z L = 11kΩ U U f r = khz ( ) 5 1 OPT = η = 15% f r = khz OPT Peak power P IN = 51.9mW f r = khz P OUT = 37.6mW f r = khz Peak power density P IN /V = 1.00Wcm -3 P OUT /V = 0.15Wcm -3 Input and Output impedance Z IN = 0.5Ω f r = 10.5 khz Z IN = 34kΩ f a = khz Z OUT = 7.kΩ f r = 10.1 khz Z OUT = 54.0kΩ f a = khz FPM - Piezoelektřina 3

23 Power density for PT - comparison Power density increased substantionally from the first PT s application K.Uchino: Piezoelectric motors and transformer, in Piezoelectricity, Springer Verlag 008 FPM - Piezoelektřina 3 3

24 Piezoelectric actuation Direct piezoelectric effect sensors Converse piezoelectric effect actuators, ultrasound generation Shear d - mode 15 S 5 FPM - Piezoelektřina 3 4

25 Piezoelectric coefficients Mechanical deformation is proportional to voltage x 3 x 1 x S 3 T S T 1 S 1 T 3 piezoelectric coefficients d 31, d 33 E 3 S S S E = d = = d d E E E = U / t Typical values d pC/N (10-1 C/N=10-1 m/v), d pC/N for PZT ceramics FPM - Piezoelektřina 3 5

26 Piezoelectric ceramic bimorph PZT Metal Bending deformation, operation in static, quasistatic or dynamic mode for the actuator Antiparallel (series) + Parallel (electrical driving of one or both elements) + FPM - Piezoelektřina 3 6

27 Bimorph parameters (Free) stroke Blocking force Resonance frequency Resonance deflection force voltage stroke FPM - Piezoelektřina 3 7

28 Stroke, deflection (Free) stroke (parallel bimorph) δ = s m 11 6s m 11 d 31 ( h + t ) L ( 3 4h + 6h t + 3ht ) m m m + s E 11 t 3 m V Without metallic plate δ = 3d 31L 4h V FPM - Piezoelektřina 3 8

29 Blocking force Blocking force (parallel bimorph) F bl = 3 d s 31 E 11 ( h + t ) L m w V Without metallic plate F bl = 3 d s 31 E 11 hw L V FPM - Piezoelektřina 3 9

30 Bimorph s resonance Resonance frequency (with metallic plate) f λ ri 1 = s A = s λ E 11 m 11 i ( h + tm ) ( 1+ B) 4πL 3ρ E s 4( 1+ B), = , λ tm B =, h = AB (1 + BC) Deflection at the resonance (without metallic plate) δ = Ω = 4h 3d Ω πf a 31 P C 11 = ρ ρ = , λ ( 1+ cos( ΩL)cosh( ΩL) ), a 3 m V sin( ΩL)sinh( ΩL) EI =, ρa P I = 1 1 wh 3 3 FPM - Piezoelektřina 3 30

31 Piezoelectric ceramic unimorph Metallic membrane Ag electrode PZT ceramics Similar to bimorph in circular arrangement Complicated mathematical solution FPM - Piezoelektřina 3 31

32 FPM - Piezoelektřina 3 3 Unimorph s parameters (static) deflection - homogeneous unimorph - heterogeneous unimorph ) ( 8 3 ) ( 1 31 a r h h h Vd r = δ ) ( 4 3 ) ( 31 a r h Vd r = δ

33 Piezoelectric ceramic actuators Bending elements (bimorph, unimorph, moonie, cymbal, THUNDER, Helimorph, RAINBOW) Deflections up to 1-3mm, forces up to 0.1N! Unimorph (membrane) PZT Bimorph Metallic plate Electrode FPM - Piezoelektřina 3 33

34 THUNDER THin layer UNimorph DrivER and sensor Special high temperature mechanical pre-stress Deflections up to 8mm, force up to 100N! FPM - Piezoelektřina 3 34

35 HELIMORPH Double spiral bimorph structure High deflection up to 5mm, force up to 1N! Drawback - brittleness FPM - Piezoelektřina 3 35

36 RAINBOW Reduced And INternally Biased Oxide Wafer Monolithic ceramic structure Internal gradient of chemical composition within plate thickness piezoelectric coefficient gradient and very high permissible deformation up to 500%! FPM - Piezoelektřina 3 36

37 Moonie and cymbal Moonie Cymbal Composite structures metallic cups and PZT plate are glued together; radial motion of ceramics is transformed to the axial motion of cups center Deflection up to 50µm, small force; very high deflection sensitivity as a sensor of hydrostatic pressure FPM - Piezoelektřina 3 37

38 Operating parameters of bending actuators FPM - Piezoelektřina 3 38

39 Vibration of body inside the viscous liquid Vibration of infinite plate damped vibrations, penetration depthδ z v = u 0 e z δ e j ( z δ ωt ) u = u 0 e jωt δ = η ρω Mechanical tension caused by viscous forces phase shift π ωρη ω τ = u cos( t + 0 ) 4 FPM - Piezoelektřina 3 39

40 Vibration of sphere in viscous liquid Viscous drag force at harmonic vibration motion u = u η ρω jωt 0e, δ F R R R = + u + ηρ 6πη 1 3πR 1 + δ ω 9δ du dt Piezoelectric bimorph is used for the vibration generation and force sensing at the same time FPM - Piezoelektřina 3 40

41 Bimorph Bimorph submerged into water PZT plate Metallic plate FPM - Piezoelektřina 3 41

42 Bimorph vibration submerged into liquid Bimorph is approximated by the sphere inside liquid Forced vibrations in liquid ( M + M ) + ( b + b) M i e = i πr 3 d y dt 3 ρ 1 + in 9δ, R dy dt b = + Ky = 6πηR δ F e jωt δ R M e, K, b in effective mass, bimorph s stiffness, internal damping FPM - Piezoelektřina 3 4

43 Bimorph s resonance Mechanical resonance of bimorph is registered electrically by the bimorph, impedance spektrum - Free in air resonance frequency - Damping inside liquid resonance frequency Width of resonance peak f i = ni π K M K ω = ω 1 γ, ω max 0 0 =, γ = M + M e 3γ e i b + bin M + M e i FPM - Piezoelektřina 3 43

44 Principle of the measurement by bimorph Calibration for the known liquid radius estimate for the equivalent sphere Impedance spektrum of bimorph vibrating inside liquid γ, ω max Viscosity and density calculation FPM - Piezoelektřina 3 44

45 Typical result Second resonance of bimorphs inside liquid FPM - Piezoelektřina 3 45

46 Resonance parameters FPM - Piezoelektřina 3 46

47 Multilayer actuators Many thin PZT layers in single segment Multilayer segment are stacked together with mechanical amplification by lever arms (Cedrat Technologies, France) High blocking forces (kn), very small deflections ( 1-10µm) without mechanical amplification FPM - Piezoelektřina 3 47

48 FPM - Piezoelektřina 3 48

49 Piezoelectric fuel injection module Cedrat Technologies, Francie FPM - Piezoelektřina 3 49

50 Actuator parameters comparison Low deflection high blocking force Craig D. Near, Piezoelectric Actuator Technology, Presented at SPIE Smart Structures and Materials Conference, February 7, 1996 FPM - Piezoelektřina 3 50

51 Deflection amplification for piezoelectric actuators Deflection is not high enough for the most direct applications Deflection amplification lever mechanism or hydraulics Lever Piston Piezostack Piezostack Hydraulic chamber FPM - Piezoelektřina 3 51

52 Piezoelectric valves Ball valve piezo-stack Poppett valve x THUNDER FPM - Piezoelektřina 3 5

53 Micropump Dosage of small volumes of liquids by piezoelectric bending elements Bimorph as an active valve element FPM - Piezoelektřina 3 53

54 Operating mode for piezoelectric element (a) transversal or (b) longitudinal mode of piezoelectric element - membrane FPM - Piezoelektřina 3 54

55 Throttle valve Throttle valve operated by ultrasonic piezoelectric motor - US patent No. 4,915,074 US motor FPM - Piezoelektřina 3 55

56 Pyroelectricity applications IR sensors for remote control Proximity sensor door opening, guarding of space, parking sensor etc. Night vision VIDICON camera Temperature distribution IR camera FPM - Piezoelektřina 3 56

57 Recommended reading J.Zelenka: Piezoelectric resonators, Elsevier, 1986 A.H.Meitzler, H.M.O Brian, H.F.Tiersten: Definition and measurement of radial mode coupling factors in piezoelectric ceramic materials with large variations in Poisson s ratio, IEEE Trans. Sonics Ultrason. SU-0, 3 (1973) N.T.Adelman, Y.Stavsky, E.Segal: Radial vibrations of axially polarized piezoelectric ceramic cylinders, J.Acoust.Soc.Am. 57, (1975) A.Ballato, J.Ballato: Accurate electrical measurements of modern ferroelectrics, Ferroelectrics 18 (1996) 9-59 IRE Standards on Piezoelectric Crystals: Determination of the Elastic, Piezoelectric, and Dielectric Constants The Electromechanical Coupling Factor, Proceedings IRE (1958) P.Hána, L.Burianová, D.Barošová, J.Zelenka, Ferroelectrics 4 (1999) N.T.Adelman, Y.Stavsky: Flexural-extensional behavior of composite piezoelectric circular plates, J.Acoust.Soc.Am. 67, 3 (1980) J.G.Smits, A.Ballato: Dynamic admittance matrix of piezoelectric cantilever bimorphs, J.Microelectromechanical Systems 3, 3 (1994) J.G.Smits, S.I.Dalke, T.K.Cooney: The constituent equations of piezoelectric bimorphs, Sensors and Actuators A 8 (1991) Q.M.Wang, L.E.Cross: Performance characteristics of piezoelectric cantilever bending actuators, Ferroelectrics 15 (1998) FPM - Piezoelektřina 3 57

58 Thank you for your attention! FPM - Piezoelektřina 3 58