Elastic properties and frequency characteristics of a piezo-active 3–0-type corundum-containing composite

Abstract

A 3-0-type composite, that contains the PZT-type ferroelectric and corundum ceramics, is characterised as a piezoelectric material with relatively stable resonance frequencies for the planar and thickness modes of oscillation. The 3-0-type composite is manufactured by solid state sintering, the resulting composite microgeometry is studied by electronic microscopy, and parameters of the composite are measured by using the resonance-antiresonance method. It is observed that almost equal volume fractions of corundum m c and air pores m p are detected in the composite samples at 0.05 < m c < 0.18. The presence of both the corundum inclusions and air pores at an almost equal volume fraction influences the elastic properties and resonance frequencies. Experimental results on the elastic properties and frequency characteristics of the composite are interpreted in terms of a model that takes into account the electromechanical interaction between the 3-0 ferroelectric ceramic/corundum and 3-0 ferroelectric ceramic/pore regions. Effective electromechanical properties and related parameters of the composite are evaluated in terms of the effective field method and dilute approximation. The studied 3-0-type composite has potential to be applied as an active element of piezoelectric transducers, sensors, and other piezotechnical devices.

Rod-Shaped Proppant Conductivity of a Hydraulic Fracture Considering Elastic-Plastic Deformation and Embedment: An Analytical Model

“…According to Osiptsov, 28 fracture permeability with rodshaped corundum proppants (X = 2.5249 mm) and rod-shaped bauxite proppants (X = 2.6284) were tested, respectively. It is noteworthy that d 0 = 0.9 mm, 28 l 0 = 11 mm, 28 E 1 = 40.49 GPa, 49 and υ 1 = 0.22 50 for corundum proppants, and d 0 = 1.2 mm, 28 l 0 = 4.8 mm, 28 E 1 = 107 GPa, 51 and υ 1 = 0.24 51 for bauxite proppants. To simulate the experimental conditions, we also used these parameters in our model calculation for this case.…”