PZT piezoelectric ceramics

The mixing performance-frequency plot does not resemble the diaphragm displacement-frequency characteristics of the PZT piezoelectric ceramic [22]. 

Since no rise in temperature is observed in the vicinity of the substrate, film production on the surface of resinous materials such as plastic is possible. As the fine raw material particles are not broken down to the molecular level in the film production process, even multicomponent complex compounds do not undergo composition shifts, so that the method has the merit of being able to produce films with a complicated composition. So far, this method has been used to produce films of PZT piezoelectric ceramics and alumina. 

Fig. 9. A typical sonochemical apparatus with direct immersion ultrasonic hom. Ultrasound can be easily introduced into a chemical reaction with good control of temperature and ambient atmosphere. The usual piezoelectric ceramic is PZT, a lead zirconate titanate ceramic. Similar designs for sealed...

Mixing can be achieved by ultrasound using lead zirconate titanate (PZT), a piezoelectric ceramic, operated in the kHz region [22], In this way, liquid streams can be moved and even turbulent-like eddies are induced. Favorably, ultrasonic action is coupled into a closed volume, a micro chamber. Here, the creation of standing waves has been reported. 

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. 

Ageing (see Section 2.7.3) affects many of the properties of piezoelectric ceramics. Most of the piezoelectric coefficients fall by a few per cent per decade although the frequency constant increases. Ageing can be accelerated and properties stabilized by heating to temperatures of about 80 °C in the case of BaTi03 and rather higher for PZT. 

An important group of piezoelectric ceramics are solid solutions of PbZrOj and PbTiOs represented as Pb(Zr, Ti)03 (and commonly referred to as PZT). At high temperature these compounds have the cubic perovskite structure (Fig. 1). In the ferroelectric phase, which is stable at room temperature, the lattice is distorted, and the asymmetry of the positive and negative ions results in a net dipole moment. Spontaneous polarization is the dipole moment per unit volume. 

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. 

The operating temperature of a piezoelectric transducer is dictated by the Curie temperature of the piezoelectric ceramic and its front-end coupling material. Commonly used ceramics are lead zirconate titanates (PZTs) whose... 

Since 1975 [63, 115], PZT transducers have often been used for the detection of photoacoustic signals from solutions. Many different piezoelectric detectors have been developed for these experiments [67, 70, 116-121]. Piezoelectric ceramics in tubular form are frequently used. Then the detectors serve simultaneouly as a container for the sample solution. Despite many proposals for the constructicm of a piezoelectric detector, it is necessary to (fcwlop a sf al cell and detector unit to perform photoae>ustk experiments on highly radic ti cotrc ive dilutions. The following requirements had to be taken into special consideration in the d gn ... 

Solid solutions between lead zirconate (PbZrOs) and lead titanate (PbTiOs) are known by the acronym PZT and are the most widely used of all piezoelectric ceramics. 

Two common piezoelectric materials are polymers (polyvinylidene fluoride, PVDF) and c mics (lead zirconate titanate, PZT). The polymer materials are soft and flexible however have lower dielectric and piezoelectric properties than ceramics. Conventional piezoelectric ceramic materials are rigid, heavy and can only be produced in block form. Ceramic materials add additional mass and stiffiiess to the host structure, especially when working with flexible/lightweight materials. This and their fragile nature limit possibilities for wearable devices. Comparisons of several piezoelectric materials are presented in Table 1. 

The heart of an acoustic emission system is the sensor. The sensors are usually made of piezoelectric ceramic material such as PZT (lead zirconium titan-... 

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. ... 

B. Andersen, E. Ringgarard, T. Bove, A. Albareda, and R. Perez, Performance of piezoelectric ceramic multiplayer components based on hard and soft PZT, Actuator... 

Thin sheets of piezoelectric materials are used in sensors, buzzers, and actuators. In addition to the conventional vibrators, pressure and acceleration sensors are now also being manufactured from these materials. Lead zirconate titanate (PZT) is one of the most common materials used for these applications. The trend is to produce thinner and thinner and smaller and smaller parts. Therefore tape casting has become the manufacturing route of choice. One of the basic applications of piezoelectric ceramics is as a gas igniter where a spark is generated by the piezoelectric under an applied mechanical stress. Microphone discs are also prepared from thin... 

Some ceramic and polymer materials also display piezoelectric properties. For ceramics these include polycrystal hne materials based on solid solutions of Pb(Zr, Ti)03. The ratio of zirconium and titanium constituents help to determine the crystal symmetry structure that results after heating and then cooling of the samples. Modern piezoelectric ceramics are referred to as PZT ceramics. Other materials such as barium, strontium, caldmn, and/or trivalent rare earth elements can be added to the ceramics in small quantities to modify the piezoelectric properties. 

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