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Having a composition closed to the morphotropic phase boundary, PZT films of 14 mu m thickness with a porosity less than 7% were prepared by the double print double firing method. At room temperature the dielectric constant, remanent polarization and coerc ...
The contribution from the irreversible displacement of non-180 degrees domain walls to the direct longitudinal piezoelectric d(33) coefficient of BaTiO3 and Pb(Zr,Ti)O-3 ceramics was determined quantitatively by using the Rayleigh law. Effects of the cryst ...
The thermal expansion of three isotropic metal-matrix composites, reinforced with SiC particles or microcellular foam, is measured between 25 degrees C and 325 degrees C. All three composites show initial coefficient of thermal expansion (CTE) values in ag ...
We introduce powder blasting for the fabrication of glass microchips. Powder blasting is a fast and cheap technique with which we pattern channels in sodalime and pyrex glass with a width down to 100µm. We combine the technique with appropriate bonding pro ...
Piezoelectric and dielectric aging was studied in Pb(Zr,Ti)O-3 (PZT) thin films and bulk ceramics. It was found that piezoelectric aging in thin films obeys the logarithmic time dependence with the relative aging rate much higher than that of the dielectri ...
Pb(Sc1/2Ta1/2)O-3 ceramics have been characterized by dielectric measurements in a wide range of frequencies (10(2)-10(9) Hz). A strong dispersion occurs with two low and high frequency contributions below the transition temperature. Only high frequency re ...
The piezoelectric response of silicon diaphragms covered with sputter-deposited PbZr0.45Ti0.55O3 (PZT) films has been investigated in view of their application in ultrasonic micro-actuators. The behaviour of resonance frequencies and quasistatic deflection ...
The time-dependent deformation of uniaxial composites reinforced with continuous stochastic fibers is examined using a one-dimensional model of a viscoelastic-plastic matrix reinforced with continuous viscoelastic fibers. The important effect of successive ...
The toughening of a ceramic by crack bridging is considered, including the heterogeneity caused simply by spatial randomness in the bridge locations, The growth of a single planar crack is investigated numerically by representing the microstructure as an a ...
Low-field piezoelectric coefficient and strain were investigated in Ca-modified PbTiO3 thin films by means of optical interferometry. A remanent piezoelectric coefficient of 70 pm/V was observed that agrees well with the values previously reported for the ...
