| Abstract Scope |
Ferroelectric materials show piezoelectric and electro-optic effects. Currently, Pb(Zr,Ti)O3 ceramics are often used as a piezoelectric material for sensor, actuator, and transducer applications while a LiNbO3 single crystal is used as an electro-optic material for a fast optical communication. However, Pb(Zr,Ti)O3 contains toxic lead and LiNbO3 has a weak electro-optic effect. My co-workers and I have developed new lead-free piezoelectric BaTiO3-Bi(Mg1/2Ti1/2)O3-BiFeO3 ceramics with electric-field-induced strain comparable to that of Pb(Zr,Ti)O3 ceramics and developed transparent Pb(Mg1/3Nb2/3)O3-PbTiO3-based ceramics with a superior electro-optic effect by a conventional pressureless sintering technique. The origin of the large piezoelectric response was found to be associated with an alignment of off-centered Bi ions, which was revealed by a synchrotron X-ray diffraction study. The results of the application of the pressureless sintering process to a lead-free system were also presented. |