Maximizing electromechanical properties of PMN materials ultrasonic transducers

In an effort to maximize electrostrictive response of PMN materials for transducer applications, a particulate coating process incorporating small amounts (<2 mol %) of chemically derived additives was used. Applying this particulate coating process to commercially available Pb(Mg/sub 1/3/Nb/sub 2/3/)O/sub 3/-PbTiO/sub 3/-BaTiO/sub 3/ (PMN-PTBT) based ceramics, improves both homogeneity and uniformity of grain size. Ceramics with improved and tailored properties for disparate applications can also be synthesized. Several additives such as Ti, Ba, and Zn were selected as promising candidates for improving the dielectric and electromechanical properties of the base PMN-PT-BT based composition. The addition of Ti with Zn nearly doubled the induced strain across most of the reduced temperature (T-T/sub max/) range-a span of 40/spl deg/C. This was achieved without increasing the associated hysteresis. The general applicability of this technique is discussed with respect to other PMN-PT and relaxor systems.