Piezoelectric and ferroelectric property in Mn-doped 0.69BiFeO3–0.04Bi(Zn1/2Ti1/2)O3–0.27BaTiO3 lead-free piezoceramics

摘要: In this article, rhombohedral 0.69BiFeO3–0.04Bi(Zn1/2Ti1/2)O3–0.27BaTiO3 (BF69–BZT4–BT27) lead-free piezoceramics were studied for the sake of obtaining high Curie point and piezoresponse. compositional engineering approach, A-site vacancies with various concentrations introduced in advance into ferroelectric ceramics by using low purities raw oxides doping MnO2. contrast to lossy BF–BT ceramics, very dielectric loss tanδ ~ 0.03 was obtained BF69–BZT4–BT27 through adding BZT third member stabilize perovskite phase MnO2 reduce oxygen a refined solid state reaction electroceramic processing. A good combination piezoelectric property 0.17 wt% MnO2-doped coarse-grained remanent polarization Pr = 32.3 μC/cm2, constant d33 145 pC/N, thickness electromechanical coupling coefficient kt 0.41 temperature TC 510 °C. The intrinsic response observed correlation switching power described constant, which is affected some extrinsic factors such as defects, microstructure grain size, residual internal stresses. Excellent thermal aging stability also experimentally demonstrated argued resulting from higher no ferroelectric–ferroelectric structural transition below BF–BZT–BT system.