Behavior of Current Flow on Lead Zirconate Titanate Surfaces during Mechanical Impact

Aman A

doi:10.4172/2321-6212.1000137

Abstract

A new mechanical stress detection technique, based on current flow at Lead Zirconium Titanate (PZT) surfaces, is described in this paper. The current flow properties of PZT were characterized by use of a tungsten indenter. The tungsten indenter was dropped from a certain height and caused mechanical impact at the PZT-sample. The tungsten pin achieved direct contact with the upper surface of the ferroelectric specimen during the impact. This procedure allowed measurements of electrical current that flew between the PZT-surface and the tungsten pin. It was shown that ferroelectric domain switching on PZT surface and plastic deformation generates this current flow during action of loading force. The current flow disappeared in a few microseconds after removal of the loading force. The measurements were carried out using different areas of force application on the PZT surface. The mechanical stress, induced by the collision, was transmitted through the sample and generated also a measureable dipole moment. In this way it was shown that PZT exhibits high sensitivity against mechanical stress by means of electrical current flow, compared to typical dipole moment measurements. This specific material property of PZT-ceramics can be used for new mechanical stress sensor designs with higher sensitivity as normal used bulky PZT-sensors.

Highlights

Sensors, which allow in-situ detection of mechanical stress, have found wide interest in several industrial branches [1,2,3]
[30] The stress detection technique based on the correlation between current emission and dipole moment generation inside bulk ferroelectric PZT-specimen is the subject of this work
It can be seen that the maxima of signal amplitudes appear with a short time delay and the maximum amplitude of the surface current (CH1) from the PZTspecimen is 6-times higher than the amplitudes, caused by the dipole moment (CH2 - 4)

Summary

Introduction

Sensors, which allow in-situ detection of mechanical stress, have found wide interest in several industrial branches [1,2,3]. [23,24] Considering the features mentioned above, a force sensor with a high mechanical resistance to stress, that generates electrical signals during the direct action of the applied force and can be used as wireless transmitter, has to be developed. In this context, it is interesting to test the current emission properties of ferroelectric PZT samples. [28,29] it can be expected that the current flow on PZT-specimen surfaces will occur in a short time during the action of the applied force In this way, the probability of overlapping of stressing events will be reduced. It should be noted that the particle layer exhibits a low damping factor and high signal transmission properties . [30] The stress detection technique based on the correlation between current emission and dipole moment generation inside bulk ferroelectric PZT-specimen is the subject of this work

Methods

Results

Conclusion