Multilayered Lead-free Textured Ceramics for Precision Actuator Applications

Description

Actuators that can transform electrical signals into induced linear/rotary motion, are desired for precision optics, fuel-injection, additive manufacturing, microscope stages etc. Piezoceramics are preferred as solid-state actuators because of the low cost, easier assembly, fast response and high degree of accuracy. Currently, most commercial actuators are made with Pb-based piezoceramics, most notably lead zirconate titanate or PZT. However, development of Pb-free piezoceramics has gained urgency due to several existing and impending government legislations limiting use of Pb in electronic and industrial materials. Among the several Pb-free piezoceramics studied, solid-solutions of (Ba,Ca)(Zr,Ti)O3 or BCZT has been the most promising due to their nearly hysteresis-freeelectrostrain response, high fatigue life and easy synthesis. Furthermore, our recent work has demonstrated that with suitable compositional modifications, Sn-doped BCZT can match traditional PZT piezoceramics in terms of their thermal stability. In this project,we propose to develop grain-oriented or textured Sn-doped BCZT ceramics, which according to our estimate can provide a maximum electrostrain of ~ 0.4%, operate up to 140 °C and exhibit fatigue life (under accelerated conditions) of at least a million cycles. Furthermore, we will develop multilayer actuators (MLA) of textured Sn-doped BCZT ceramics, which will pave the way for their commercial adoption.