PZT (lead zirconate titanate) multilayer actuators were of interest due to their small volume, fast response, low power consumption and low driving voltage. But this multilayer actuator had some problems. However, due to internal stress around electrodes, crack and delamination were very important issues. Around the edge of conventional inter-digital electrodes, non-uniform electric field generates the stress concentration, which causes the ceramic crack and delamination. The internal stress distribution in multilayer actuator was analysed by a numerical simulation. And by using float electrode, multilayer actuator was manufactured to decrease internal stress concentration of inter-digital electrode. The float electrode could suppress the electric field concentration and cracking in the actuator. Destruction mechanism in multilayer ceramic actuators has been investigated under cyclic electric fields. Crack propagation has been observed dynamically by using optical microscopy, and the accompanying characteristic of acoustic emission was measured.
Bibliographical noteFunding Information:
This research was supported by a grant from the Center for Advanced Materials Processing of 21 century Frontier R&D program funded by the Ministry of Science and Technology of the Republic of Korea.
- Floating electrode
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics