The Materials Science and Applications of Smart Electronic Ceramics September 26, 2011, SC 5326
Richard E. Eitel
Department of Chemical and Materials Engineering University of Kentucky, Lexington, KY
Smart materials can be defined as materials which “respond to an external change in a useful manner without outside assistance (Newnham, 2005).” In our group’s research, we focus on the synthesis and optimization of smart electroceramic materials and devices through a detailed understanding of fundamental structure-property relationships. The current talk will highlight recent contributions to materials science advances and engineered device applications of “smart” piezoelectric ceramics.
The first portion of the talk will focus on the BiFeO3-BaTiO3 high performance lead-free piezoelectric ceramic system developed at University of Kentucky. This material system is being proposed as an environmentally friendly alternative to current lead based materials used in piezoelectric actuator applications. This material exhibits large room temperature piezoelectric coefficients and suitable temperature stability for commercial applications. In-situ electromechanical testing results and extensive structural analysis reveal changes in local structure under large electrical fields which help to explain the origin of the large piezoelectric response in this material system.
The second portion of the talk will discuss the optimization of a thick film piezoelectric ceramic material suitable for integration into ceramic micro electro mechanical systems (cMEMS). Liquid phase sintering additives were initially used to reduce the sintering temperature of the starting material. The analytical master sintering model was then used to assist in the development of a sintering process which would enable cofiring the developed material with commercially available low temperature cofire ceramic (LTCC) formulations. Ultimately, these materials and methods enabled the fabrication and testing of a compact piezoelectrically actuated micropump for lab-on-a-chip applications.