Annealing-Dependent Morphotropic Phase Boundary in the BiMg<sub>0.5</sub>Ti<sub>0.5</sub>O<sub>3</sub>–BiZn<sub>0.5</sub>Ti<sub>0.5</sub>O<sub>3</sub> Perovskite System
João Pedro V. Cardoso,
Vladimir V. Shvartsman,
Anatoli V. Pushkarev,
Yuriy V. Radyush,
Nikolai M. Olekhnovich,
Dmitry D. Khalyavin,
Erik Čižmár,
Alexander Feher,
Andrei N. Salak
Affiliations
João Pedro V. Cardoso
Department of Materials and Ceramics Engineering and CICECO—Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal
Vladimir V. Shvartsman
Institute for Materials Science and CENIDE—Centre for Nanointegration Duisburg-Essen, University of Duisburg-Essen, 45141 Essen, Germany
Anatoli V. Pushkarev
Scientific-Practical Materials Research Centre of NASB, 220072 Minsk, Belarus
Yuriy V. Radyush
Scientific-Practical Materials Research Centre of NASB, 220072 Minsk, Belarus
Nikolai M. Olekhnovich
Scientific-Practical Materials Research Centre of NASB, 220072 Minsk, Belarus
The annealing behavior of (1-x)BiMg0.5Ti0.5O3–xBiZn0.5Ti0.5O3 [(1-x)BMT–xBZT] perovskite solid solutions synthesized under high pressure was studied in situ via X-ray diffraction and piezoresponse force microscopy. The as prepared ceramics show a morphotropic phase boundary (MPB) between the non-polar orthorhombic and ferroelectric tetragonal states at 75 mol. % BZT. It is shown that annealing above 573 K results in irreversible changes in the phase diagram. Namely, for compositions with 0.2 x < 0.6, the initial orthorhombic phase transforms into a ferroelectric rhombohedral phase. The new MPB between the rhombohedral and tetragonal phases lies at a lower BZT content of 60 mol. %. The phase diagram of the BMT–BZT annealed ceramics is formally analogous to that of the commercial piezoelectric material lead zirconate titanate. This makes the BMT–BZT system promising for the development of environmentally friendly piezoelectric ceramics.