Morphotropic phase boundary (MPB) compositions separating rhombohedral and tetragonal phases in the (1−x−y)Pb(Mg1/3Ta2/3)O3–yPbZrO3–xPbTiO3 (PMT–PZ–PT100x) ternary solid solution system were characterized using X-ray diffraction and dielectric, piezoelectric properties. This work focused on compositions with a PZ content fixed at y=0.2, with an MPB composition found to be located at x=0.4. Piezoelectric coefficients and dielectric permittivity were found to be on the order of d33=580 pC/N and 4100, respectively. Acceptor modification using manganese was found to induce a “hardening” effect in 0.4PMT–0.2PZ–0.4PT, with decreased piezoelectric coefficients d33 and dielectric loss and increased mechanical quality factor Q. Piezoelectric coefficients d33, Q values, and dielectric loss were found to be 500 pC/N, 2000, and 0.4%, respectively, for 0.4PMT–0.2PZ–0.4PT with MnO2 dopant levels around 0.5 wt%. The figure of merit (product of Q and d33) was found to be on the order of 1 × 106, significantly higher when compared with other hard piezoelectric PZT materials. Specifically, the PMT–PZ–PT materials may be attractive candidates for high-power ultrasonic applications, particularly fine-scale components that require relating high permittivities.
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, School of Material Science and Engineering, Wuhan University of Technology, Wuhan, China 430070 2:
Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania, 16802