Piezoelectric ceramics composites

Runt, J. and Galgoci, E. C., Polymer/piezoelectric ceramic composites Polystyrene and poly(methyl methacrylate) with PZT, J. AppL Polym. ScL, 29, 611-617 (1984). 

Newnham, R. E. and Runt, J. P., Polymer-piezoelectric ceramic composites, Polym. News, 10,132-138 (1984). 

Piezocomposite transducers are an advancement of piezoelectric ceramics. Instead of the classic piezoceramic material, a compound of polymer and piezoceramic is used for the composite element to improve specific properties. The 1-3 structure, which is nowadays mostly used as transducer material, refers to parallel ceramic rods incorporated in an epoxy-resin matrix (see Fig. 1). 

Ferroelectric—polymer composite devices have been developed for large-area transducers, active noise control, and medical imaging appHcations. North American Philips, Hewlett-Packard, and Toshiba make composite medical imaging probes for in-house use. Krautkramer Branson Co. produces the same purpose composite transducer for the open market. NTK Technical Ceramics and Mitsubishi Petrochemical market ferroelectric—polymer composite materials (108) for various device appHcations, such as a towed array hydrophone and robotic use. Whereas the composite market is growing with the invention of new devices, total unit volume and doUar amounts are small compared to the ferroelectric capacitor and ferroelectric—piezoelectric ceramic markets (see Medical imaging technology). 

The bending piezoelectricity in drawn and polarized polymer films was studied in detail by Kawai (1) (1970). Kitayama and Nakayama (1971) reported a very high piezoelectricity in composite films of polymer (PVDF, nylon 11, PVC) and powdered ceramics (barium titanate, PZT) after poling. In the case of PVDF and nylon, the piezoelectric constant increase by a factor of 102 when the ceramics make up 50% of the volume. The pyroelectricity and optical nonlinearity of polarized PVDF films have been studied by Bergmann, McFee, and Crane (1971). 

Kitayama, T., Nakayama, H. Piezoelectricity of composite systems of polymer and powdered ferroelectric ceramics. 18 th Meeting on Appl. Phys. Japan (Apr. 1971) Tokyo. 

The first piezoceramic to be developed commercially was BaTi03, the model ferroelectric discussed earlier (see Section 2.7.3). By the 1950s the solid solution system Pb(Ti,Zr)03 (PZT), which also has the perovskite structure, was found to be ferroelectric and PZT compositions are now the most widely exploited of all piezoelectric ceramics. The following outline description of their properties and fabrication introduces important ideas for the following discussion of the tailoring of piezoceramics, including PZT, for specific applications. It is assumed that the reader has studied Sections 2.3 and 2.7.3. 

Janas, V.E. and Safari, A. (1995) Overview of fine-scale piezoelectric ceramic/ polymer composite processing, J. Am. Ceram. Soc., 78, 2945-55. 

Ceramic capacitors are prepared with their chemical compositions placing them close to a ferroelectric-paraelectric phase boundary, where the dielectric permittivity is anomalously high. These materials are commonly based on BaTiOs which is similar in structure and properties to the piezoelectric ceramics. 

Composite piezoelectric transducers made from poled Pb-Ti-Zr (PZT) ceramics and epoxy polymers form an interesting family of materials which highlight the advantages of composite structures in improving coupled properties in soilds for transduction applications A number of different connection patterns have been fabricated with the piezoelectric ceramic in the form of spheres, fibers, layered, or three-dimensional skeletons Adding a polymer phase lowers the density, the dielectric constant, and the mechanical stiffness of the composite, thereby altering electric field and concentrating mechanical stresses on the piezoelectric ceramic phase. 

Nunes-Pereira, J., Sencadas, V, Correia, V, Rocha, J.G., Lanceros-M ndez, S., 2013. Energy harvesting performance of piezoelectric electrospun polymer fibers and polymer/ceramic composites. Sensors Actuat. A Phys. 196,55-62. 

The present paper considers piezoelectric ceramics as key functional material in composites and structures. Most of piezoelectrics presently exploited commercially are solid solutions based on lead zirconate titanate (PZT) ceramics. Still, compositional developments within the PZT family are performed to meet custom requirements perfectly. Lead flee piezoelectrics, such as the sodium potassium niobate solid solutiom and bismuth sochum titanate solid solutions became the topic of much research at the end of the 1990s, which is due to increased environmental avrareness. ... 

The ceramic compositions of (l-x)(Ko,48Nao4iLio,04)Nb03-xBaTi03 [(l-x)KNLN-xBT] and 0.99(Ko,48Nao,48Lio,04)(Nbi.ySby)03-0.01BaTi03 (KNLN. ySy-BT), were used as model systems to illustrate the variation of piezoelectric constant. The ceramics were synthesized by conventional solid-... 

Banno H (1983) Recent developments of piezoelectric ceramic products and composites of synthetic rubber and piezoelectric ceramic particles. Ferroelectrics 50 3-12 Bauer F, Brown LF, Fukada E (eds.) (1995) Special issue on piezo/pyro/ferroelectric polymers. Ferroelectrics 171 1 03... 

Ilyaev AB, Umarov BS, Shabanova LA, Dubovik MF (1986) Temperature dependence of electromechanical properties of LGS crystals. Phys Stat Sol (a) 98 K109-K114 IRE Standards on Piezoelectric crystals. Proc IRE (1949) 37 1378 Jaffe B, Cook WR, Jaffe H (1971) Piezoelectric ceramics. Academic, London Jayasundere N, Smith BV (1993) Dielectric constant for binary piezoelectric 0-3 composites. J Appl Phys 73 2462-2466... 

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