Lead titanate zirconate

The development of active ceramic-polymer composites was undertaken for underwater hydrophones having hydrostatic piezoelectric coefficients larger than those of the commonly used lead zirconate titanate (PZT) ceramics (60—70). It has been demonstrated that certain composite hydrophone materials are two to three orders of magnitude more sensitive than PZT ceramics while satisfying such other requirements as pressure dependency of sensitivity. The idea of composite ferroelectrics has been extended to other appHcations such as ultrasonic transducers for acoustic imaging, thermistors having both negative and positive temperature coefficients of resistance, and active sound absorbers. 

Nickel is being used ia magnetostrictive transducers ia some ultrasonic devices, eg, solderiag irons and ultrasonic cleaners, because of its moderate magnetostriction and availabiUty. This market, however, is dominated by piezoelectric transducers of lead zirconate—titanate (PZT) (see Ultrasonics). 

Zirconate compounds exhibit several interesting properties. Lead zirconate—titanate [12626-81 -2] compositions display piezoelectric properties which are utilized in the production of EM-coupled mode filters, resonators in microprocessor clocks, photoflash actuators, phonograph cartridges, gas... 

PZT (lead zirconate titanate) and PLZT (lead lanthanum zirconate titanate) combine ferroelectic, optical, and electronic properties and are used in optoelectronic and piezoelectric devices. Powders for hot pressing produced by CVD are being investigated. 

Material Quartz and ceramic materials (Barium titanate (BaTiOQ, Lead metaniobate (PbNb2Os) and the mixed crystal Lead-zirconate titanate) Nickel or an alloy of Nickel. Also, some other high-tech alloys with ferrite materials (MFe204, M = divalent metal like Ni, Zn and Pb)... 

These reactions have been studied in detail for materials such as silica, and understanding of reaction mechanisms, as well as of the role of the precursor and catalyst (acid or base), has been well documented.63,64 Similar studies have been carried out in other material systems, most notably, lead zirconate titanate [Pb(Zr,Ti)03 PZT].52,65-68 For multicomponent (mixed-metal) systems such as those noted, prehydrolysis of less reactive alkoxides is sometimes employed to improve solution compositional uniformity. Other synthetic strategies to achieve molecular level mixing of reagents have also been employed. Here, synthesis of mixed-metal alkoxides has been a focus of investigators.40-42 A key point is to restrict the amount of water and to control how it is added to form solubalizable precursor species, rather than to induce precipitation.1,52,69,70... 

The alcohol exchange reaction was shown above in equation (2). The reactive alkoxy group (OR) is replaced by an alkoxy group that has less hydrolysis sensitivity (OR ). A representative example here is the use of reagents such as zirconium n-propoxide and titanium /-propoxide, both of which possess polar bonds, for the production of lead zirconate titanate films. Commonly in these processes, R OH is 2-methoxyethanol (CH3OCH2CH2OH), which is generally present as a bidentate ligand.35... 

Barrow, D. A. Petroff, T. E. Tandon, R. P Sayer, M. 1997. Characterization of thick lead zirconate titanate films fabricated using a new sol gel based process. I. Appl. Phys. 81 876-881. 

Merklein, S. Sporn, D. Schonecker, A. 1992. Crystallization behavior and electrical properties of wet-chemically deposited lead zirconate titanate. In Ferroelectric Thin Films III, edited by Tuttle, B. A. Myers, E. R. Desu, S. B. Larsen, P. K. Mat. Res. Soc. Symp. Proc. 310 263-268. 

Losego, M. D. Trolier-McKinstry, S. 2004. Mist deposition of micron thick lead zirconate titanate thick films. In Ferroelectric Thin Films XII, edited by Hoffmann-Eifert, S. Funakubo, H. Kingon, A. I. Koutsaroff, I. Joshi, V. Mat. Res. Soc. Symp. Proc. 784(C11.28) l-6. 

Reaney, I. M. Brooks, K. Klissurka, R. Pawlaczyk, C. Setter, N. 1994. Use of transmission electron microscopy for the characterization of rapid thermally annealed solution-gel, lead zirconate titanate films. /. Am. Ceram. Soc. 77 1209-1216. 

A variety of piezoelectric transducers have been employed for PAC. Ceramic transducers, usually lead zirconate titanate, are most commonly employed because of their sensitivity, time resolution and commercial availability. However, their acoustic response is often dominated by their own resonance, and so polymeric film detectors, such as polyvinylidenedifluoride, are often used. These piezoelectric materials are non-resonant, but not as sensitive as the ceramic detectors. Again, each detector has its own advantages (and disadvantages).14,15... 

Abstract A short review is given of the status of MRAMs and FRAMs, summarizing both industry prototype production and university research. This comparison seems especially timely since this month (July 2006) Freescale have announced the first commercial MRAM product (4 Mb), and the race is now fairly even between the Samsung 32 Mb lead zirconate titanate FRAM and the Matsushita 4 Mb strontium bismuth tantalate FRAM. 

This 4 Mb FRAM utilizes lead zirconate titanate (PZT) as the active memory element a similar prototype has been made by Matsushita/Panasonic using strontium bismuth tantalate (SET). A 32-Mb SET memory has more recently been announced by Samsung. Device performances are similar in each case. The PZT device has the advantage that it can be processed at lower temperatures (450 °C, compared with ca. 650 °C for SET) the SET devices have the environmental advantage that they are lead-free. 

PZr is the trade name of the lead zirconate titanate piezoelectric ceramics of one of its largest producer, Vcmiiron. It is also commonly used in the scientific literature as a standard acronym. 

See Local density of states Lead zirconate titanate ceramics 217—220 chemical composition 218 coupling constants 220 Curie point 218 depoling field 219 piezoelectric constants 220 quality number 219 Leading-Bloch-waves approximation 123 Level motion-demagnifier 271 Liquid-crystal molecules 338 Living cell 341... 

See Lead zirconate titanate ceramics Piezoelectric constants 220 Piezoelectricity 213—221... 

See Lead zirconate titanate ceramics Quality number 219 Quantum transmission 59 Reciprocal space 123, 353 Reciprocity principle 88 Reconstruction 14, 327 Au(lll) 327 DAS model 16 Si(lll)-2X1 14 Recursion relations 352 Repulsive atomic force 185, 192 Resonance frequency 234, 241 piezoelectric scanners 234 vibration isolation system 241 Resonance interactions 171, 177 and tunneling 177 Resonance theory of the chemical bond 172... 

A wide array of ferroelectric, piezoelectric and pyroelectric materials have titanium, zirconium and zinc metal cations as part of their elemental composition Many electrical materials based on titanium oxide (titanates) and zirconium oxide (zirconates) are known to have structures based on perovskite-type oxide lattices Barium titanate, BaTiOs and a diverse compositional range of PZT materials (lead zirconate titanates, Pb Zr Tij-yOs) and PLZT materials (lead lanthanum zirconate titanates, PbxLai-xZryTii-yOs) are among these perovskite-type electrical materials. 

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