Lead-Free Multilayer Piezoceramic Composites: Effect of Cosintering on Electromechanical Properties.

The macroscopic electromechanical behavior of lead-free multilayer composites was characterized from room temperature to 150 °C. The polar seed component consisted of a nonergodic relaxor (BiNa)TiO-7BaTiO, with an electric-field-induced long-range ferroelectric order, whereas the nonpolar matrix was an ergodic relaxor Bi(NaK) TiO-6BiAlO that undergoes a reversible electric-field-induced macroscopic nonpolar-to-polar transition. Microstructural evidence of the effects of cosintering are demonstrated through examination of grain size, interdiffusion, and pore structure.

Enhancing electromechanical properties of lead-free ferroelectrics with bilayer ceramic/ceramic composites.

The macroscopic electromechanical behavior of lead-free bilayer composites was characterized at room temperature. One layer consisted of a nonergodic relaxor, (Bi1/2Na1/2)TiO3-7BaTiO3, with an electric-field-induced longrange ferroelectric order, whereas the other is understood to be an ergodic relaxor [(Bi1/2Na1/2)TiO3-25SrTiO3] that undergoes a reversible electric-field-induced macroscopic nonpolar-to-polar transition. Microstructural evidence of a bilayer with low diffusion between the two components is also demonstrated.