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Research describing the effect of dc electric fields on the behavior of cadmium pyroniobate is presented. In particular the field dependence of the dielectric constant and loss are investigated.

Research describing the complex dielectric permittivity of lossy ceramic composites is presented. In particular an AlN composite is investigated with regard to the phasing out of BeO composites on environmental and safety grounds.

A study investigated the use of mechanical indentation with conducting spherical indentors, with zero potential basis, as a technique for characterizing piezoelectric ceramic-polymer 1-3 composites. The measured currents as a function of load, at larger loads, are in qualitative agreement with those predicted using analytical and finite element models based on given electromechanical properties of the constituents.

The effective dielectric, piezoelectric and elastic constants of polycrystalline ferroelectric materials were determined from single-crystal data through an advanced technique of effective medium. The technique considers the piezoelectric interactions between grains in full measure. The material constants were found to be dependent on the remanent polarization for bulk BaTiO3 and PbTiO3 polarized ceramics. Dielectric and elastic constants were also obtained for unpolarized c- and a-textured ferroelectric thin films deposited on cubic and amorphous substrates.

Research was conducted to examine the dielectric properties of Bi doped SrTiO3 ceramics in the temperature range 500-800 K. Ceramic samples were prepared using solid state reaction. Temperature dependence of dielectric properties was calculated while the temperature of samples was increasing at a rate of 0.7 K/min an readings were taken at every 3 K. Results indicate that the permittivity peaks are related to the movement of oxygen ions.

Research was conducted to investigate the fragmentation and flow of hot-pressed silicon carbide under high-strain-rate deformation and comminution of silicon carbide. Three different silicon carbides having similar average grain size were examined based on their fragmentation and large deformation of ceramics. Results indicate that high-strain-rate deformation of comminuted SiC is applicable in the validation of computer models for penetration process.

The influence of mobile space charges on the ferroelectric properties is investigated by measuring the ac complex impedance and thermal depolarization current for aged (K0.50Na0.50)2(Sr0.75Ba0.25)4Nb10O30 ceramic samples. An analysis of the impedance behavior was done through an equivalent circuit composed of a capacitor connected in series with a parallel resistor-capacitor circuit. Experimental results show that the dielectric relaxation consists of two mechanisms which are discussed.

(Pb,La)(Zr,Ti)O3 and Pb(Zr,Ti)O3 bulk ceramics and thin films reveal two photoinduced modifications in their hysteresis properties, a voltage shift and a reduction of switchable polarization. Photogenerated charge capture at domain boundaries results in a decrease in internal depolarizing fields and accounts for the photoinduced-changes in hysteresis. Polarization-inhibition depends on exponential time while voltage shift depends on stretched exponential time and thickness of the film. The relaxation times of both effects is same, but that of the voltage shift effect decreases when light intensity increases.

X-ray measurements of the dielectric constant, dielectric polarization, crystallographic parameters and electrostrictive strain of lead zirconate titanate stannate ceramics with lanthanum reveal that the electric field activates the transition from the antiferroelectric to ferroelectric phase. The transition occurs with a volume modification of 0.35 cubic Angstrom units and is the most dominant process in the strain. The parameters of ceramics depend on the technology of ceramic formation while the backward switching critical field depends on temperature.

The electrical properties of lead-lanthanum zirconate-titanate-x/95/5 ceramics with an La content ranging from 4 to 5% were investigated. The results showed that La dopants exerted a strong effect on the antiferroelectric-ferroelectric-paraelectric phase transitions and properties of the material. Ferroelectric microdomains induced the formation of properties like those observed in ferroelectric relaxors.

The results of a numerical study conducted by R Feng et al and Feng and YM Gupta were analyzed. The study was carried out to gain an insight into the dynamic response of lateral piezoresisting stress gauges. The results were investigated to highlight the difficulties with the simulations and to focus on several conclusions concerning the choice of optimal gauge dimensions and emplacement methods.

The comment made by Z. Rosenberg regarding two studies conducted on lateral piezoresistance gauges in shocked ceramics and shocked solids were found to be invalid. There were also misleading statements pertaining to the previous studies that Rosenberg reviewed. A response to the comment is presented which focuses on such points as the agreement between his assumptions and the reviewed dynamic calculations and his ad hoc statements about the numerical calculations.