Piezoelectric Materials at Elevated Temperature

Abstract

Piezoelectric ceramic patches are the mainstay for actuating and sensing in smart structures, but these patches are limited in the temperature range in which they can operate. Operation at temperatures above ambient is desired for new applications of smart structures, including in aircraft, turbine engine components, space vehicles, and others. The decrease in the actuation and sensing capability with increasing temperature is mainly due to the loss of the piezoelectric properties through depoling. The decrease in performance is also due to the compliance of the adhesive used to bond the patch to the structure, the insulating film covering the patch, and the inside adhesive bonding the film to the wafer. This paper discusses the general properties and modeling of piezoelectric materials, and then experimentally characterizes the performance of piezoelectric ceramic patches used as sensors bonded onto an aluminum beam operating at moderately elevated temperatures. It is shown that the piezoelectric property of the sensor decreases with increasing temperature until the properties are almost completely lost, and also the piezoelectric properties return each time when the sensor is cooled. Finally, high temperature nanotechnology is investigated as an approach that might replace piezoelectric ceramics for sensing and actuating of smart structures at high temperatures.

Investigating the thermally induced acoustoelastic effect in isotropic media with Lamb waves

“…Several studies have documented experimental results that demonstrate environmental factors, such as isothermal temperature changes 3,4 or applied stress, 16,17 change Lamb wave velocity. Only a few studies have theoretical work with experimental validation, which addresses the change of dispersive Lamb wave velocities in metallic plates over a wide range of frequencies with respect to environmental factors; Gandhi et al address the case of biaxial applied stress 17,18 and Dodson and Inman investigate the case of isothermal temperature variation.…”

“…1,2 Environmental effects such as temperature, 3,4 applied stress, 5,6 and surface loading 7,8 change the propagation velocity of guided waves and impede the implementation of traditional health monitoring methods in aerospace structures due to false positive readings. One of the biggest challenges in using guided waves for health monitoring is developing damage detection techniques that are sensitive to damage but not environmental changes.…”

Piezoelectric materials for high temperature transducers and actuators

“…It is already well established but limited to operating temperatures \260°C [5] due to the majority of devices relying on the ubiquitous piezoelectric ceramic 'lead zirconate titanate' or PZT, to produce and detect the acoustic signal. Significant effort has gone into developing new materials to meet the increasing demand for piezoelectric elements that can withstand elevated temperature ranges.…”

Microstructure and temperature dependence of properties of morphotropic phase boundary Bi(Mg1/2Ti1/2)O3-PbTiO3 piezoceramics processed by conventional routes

“…It has acceptable piezoelectric properties (d 33 = 85 pC N −1 ), but still relatively low operating temperature (T max ∼ 300 • C). 2 There is an increasing demand for materials for operation at higher temperatures (300-500 • C), 10 and bismuth-layered structure ferroelectrics (BLSF) are good candidates because of their very high Curie temperature. These materials have as general formula (Bi 2 O 2 )(A n−1 B n O 3n+1 ) and their crystalline structure is built by alternating [Bi 2 O 2 ] 2+ and n pseudo-perovskite layers.…”