IMF2017

Relaxor ferroelectrics remain essential for high power transduction applications due to their exceptional electromechanical response. In single crystal form at near-morphotropic compositions, high-coupling modes are stable under typical naval operating conditions. Over the past two decades, the Navy has interfaced directly with single crystal manufacturers worldwide in a collaborative effort to achieve the required stability and electromechanical performance. While ideal electromechanical performance is realized in single crystal form due to full microstructural alignment, the lack of a complex grain structure is disadvantageous to stable operation under large field drive and/or tensile loading. Crystallographic texturing of a polycrystalline ceramic affords a means to achieve enhanced electromechanical performance without sacrificing mechanical robustness. Adhering to the same methodology put forth during the development of relaxor single crystals, the Navy has begun to invest in the realm of textured ceramic materials. In this work, [001] oriented and poled Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ (PMN-PT) and Pb(Mg_1/3Nb_2/3)O₃-Pb(Zr,Ti)O₃ (PMN-PZT) textured ceramics are evaluated and compared with their single crystal counterparts. Electromechanical response under large drive fields (E ~ 1.5 MV/m) and uniaxial compression is investigated as a function of temperature. For PMN-PT, the role of dopants on the losses during operation is examined, while for PMN-PZT the mechanical strength and fracture toughness under bending is explored. In total, lessons learned during the development of relaxor single crystals are being actively applied to textured ceramics to minimize development time and address known shortcomings of relaxor ferroelectrics.