Piezoelectric Ceramic Products FUNDAMENTALS, CHARACTERISTICS AND APPLICATIONS PIEZOCERAMIC MATERIALS PIEZO TECHNOLOGY

Contents PI Ceramic – Leaders in Piezoelectric Technology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Product Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Fundamentals of Piezo Technology Piezoelectric Effect and Piezo Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Electromechanics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 . . Dynamic...

LEADERS IN PIEZOELECTRIC TECHNOLOGY PI Ceramic is one of the world's market leaders for piezoelectric actuators and sensors . PI Ceramic provides everything related to piezo ceramics, from the material and components right through to the complete integration. PI Ceramic provides system solutions for research and industry in all high-tech markets including medical engineering, mechanical engineering and automobile manufacture, or semiconductor technology . Materials Research and Development PI Ceramic develops all its piezoceramic materials itself. To this end PI Ceramic maintains its own laboratories,...

PI Ceramic provides ■ Piezoceramic materials (PZT) ■ Piezoceramic components ■ Customized and application-specific ultrasonic transducers/transducers ■ PICMA® monolithic multilayer piezo actuators ■ Miniature piezo actuators ■ PICMA® multilayer bender actuators ■ PICA high-load piezo actuator ■ PT Tube piezo actuators ■ Preloaded actuators with casing ■ Piezocomposites -DuraAct patch transducers Our aim is to maintain high, tested quality for both our standard products and for custom-engineered components . We want you, our customers, to be satisfied with the performance of our products . At...

Experience and Know-How STATE-OF-THE-ART MANUFACTURING TECHNOLOGY Developing and manufacturing piezoceramic components are very complex processes. PI Ceramic has many years of experience in this field and has developed sophisticated manufacturing methods. Its machines and equipment are state of the art. Rapid Prototyping The requirements are realized quickly and flexibly in close liaison with the customer. Prototypes and small production runs of custom-engineered piezo components are available after very short processing times. The manufacturing conditions, i.e. the composition of the material...

Product Overview IN-HOUSE DEVELOPMENT AND PRODUCTION Piezoelectric Components ■ Various different versions in many different geometries such as disks, plates, tubes, customized shapes ■ High resonant frequencies to 20 MHz OEM Adaptations ■ Piezo transducers for ultrasonic applications ■ Assembly of complete transducer components ■ 2D or line arrays DuraAct Piezo Patch Transducers ■ Actuator or sensor, structural health monitoring ■ Bendable and robust, preloaded due to lamination Control Electronics ■ Different performance classes ■ OEM modules and benchtop devices

PICMA® Multilayer Piezo Actuators ! High stiffness PICA High-Load Actuators ! PICMA® Multilayer Bending Actuators ! Contractors, variable contours Piezo Actuators with Customized Equipment ! P osition and temperature monitoring PIEZO TECHNOLOG

Piezoelectric Effect and Piezo Technology 2(Y) Piezoelectric Ceramics … Piezoelectric materials convert electrical energy into mechanical energy and vice versa. The piezoelectric effect is now used in many everyday products such as lighters, loudspeakers and signal transducers. Piezo actuator technology has also gained acceptance in automotive technology, because piezocontrolled injection valves in combustion engines reduce the transition times and significantly improve the smoothness and exhaust gas quality. The word “piezo“ is derived from the Greek word for pressure. In 1880 Jacques and Pierre...

which is degraded again when the mecha­ nical, thermal and electrical limit values of ­ the material are exceeded (see Fig. 3). The ­ ceramic now exhibits piezoelectric properties and will change dimensions when an electric voltage is applied. Some PZT ceramics must be poled at an elevated temperature. – When the permissible operating temperature is exceeded, the polarized ceramic d ­ epolarizes. The degree of depolarization is depending on the Curie temperature of the material. (1) (2) – One effect of the spontaneous polarization is that the discrete PZT crystallites become p ­ iezoelectric....

T mechanical stress E electric field S mechanical strain d piezoelectric charge coefficient εT dielectric permittivity (for T = constant) sE elastic coefficient (for E = constant) Fig. 5. Orthogonal coordinate system to describe the properties of a poled piezoelectric ceramic. The polarization vector is parallel to the 3 (Z)-axis. ε33T permittivity value in the polarization ­ irection when an electric field is d a ­ pplied parallel to the direction of the polarity (direction 3), under conditions of constant mechanical stress (T = 0: “free“ permittivity). D = d T + εT E S = sE T + d E These relationships...

Elastic Compliance s. The elastic compliance coefficient s is the ratio of the relative deformation S to the mechanical stress T. Mechanical and electrical energy are mutually dependent, the electrical boundary conditions such as the electric flux density D and field E must therefore be taken into consideration Examples s33E the ratio of the mechanical strain in direction 3 to the mechanical stress in the direction 3, at constant electric field (for E = 0: short circuit) . sssD the ratio of a shear strain to the effective shear stress at constant dielectric displacement (for D = 0: open electrodes) The...

Most piezoelectric material parameters are OD 3 determined by means of impedance mea- OD >> TH 2 TH U P U P OD >> TH L 1 surements on special test bodies according U 3 2 to the European Standard EN L50324-2 atP L >> W >> TH TH U 1 3 resonance. U P L >> W >> TH 2 Fig. 6. Equivalent circuit diagram OD 3 of a piezoelectric resonator 2 TH 1 L – – – – TH W OD + + W +U +– P OD >> TH – – – + + 2 TH U P OD >> TH L 1 + + + + – – + + + – Shape + + +U Oscillations + U 3 + 3 – + 1 – L >> W >> TH P 2 P L >> W >> TH – – – 2 – – – – – – – – –   – + TH –+ –+ + +– TH – 1 1 + Type + + Mechanical Series resonance...