High Strain Piezoelectric Multilayer Actuators?A Material Science and Engineering Challenge

Abstract

Piezoelectric actuators are at an important stage of their development into a large component market. This market pull is for dynamically driven actuators for Diesel injector valves in automobiles. Cost, yield, and reliability are important concerns for the automobile industry. A number of these concerns relate back to basic material science issues in the manufacture of the piezoelectric actuators. This paper discusses material development of the piezoelectric ceramic and new opportunities for higher temperature materials. An important consideration in developing low-fire ceramics is the flux selection for a given system, and these must be selected to limit electrodeceramic interface reactions in both Ag/Pd and copper-metallized electrode actuators.

Progress in engineering high strain lead-free piezoelectric ceramics

“…However, it can be difficult to appreciate the significant limitations associated with the vast majority of these materials. Zhang et al have proposed the use of graphs of d 33 over T d in order to make more reliable comparisons both among and between lead-based and lead-free piezoelectrics materials [4,14,118]. Such plots provide a concise illustration of the relationship between the room-temperature piezoelectric coefficient and phase transition temperatures.…”

“…Current applications of piezoelectric devices extend to automotive fuel injection, accelerometers, piezoelectric transformers and motors, vibration control, micropositioning systems, ultrasound sensors and generators, inkjet printers and many more [2][3][4][5]. In the particular case of piezoelectric actuator applications, the piezoelectric strain coefficient (d i j ) and its temperature dependence are the critical performance metrics.…”

Domain switching energies: Mechanical versus electrical loading in La-doped bismuth ferrite–lead titanate

“…[1][2][3] A significant amount of the materials used in these applications are polycrystalline ferroelectrics with perovskite structure, such as PZT. These materials exhibit significant nonlinearity primarily caused by domain wall motion.…”

“…There are, however, certain limitations. In PbTiO 3 ceramics the high tetragonal distortion-quantified by the c/a ratio-induces high internal stresses within the ceramic when cooling down from the paraelectric cubic phase to the ferroelectric tetragonal phase. 8 For a c/a ratio of 1.06 these internal stresses are high enough to destroy the ceramic upon cooling from sintering temperatures.…”

Strain Mechanisms in Lead-Free Ferroelectrics for Actuators

“…Selection of proper electrodes is of crucial importance considering that most of the cost of an actuator is due to the metal electrodes. 467 Biocompatibility studies also offer a great opportunity to implement lead-free piezoelectrics in medical applications. It was noted that for specific niche markets lead-free piezoceramic have superior properties than lead-containing counterparts.…”