Mn and Sm doped lead titanate ceramic fibers and fiber/epoxy 13 composites

Abstract

Manganese and samarium doped lead titanate [Pb[sub 0.85]Sm[sub 0.10](Ti[sub 0.98]Mn[sub 0.02])O₃, PSmT] fibers were prepared by sol-gel method. The micrographs obtained using scanning electron microscope show that PSmT ceramic fibers are round and dense. The diameter of the fibers was in the range of 30-35 µm. The crystalline grains size is ~2.5 µm. The micrographs obtained using transmission electron microscope also unveiled the layer-by-layer 90° domains in the grains. X-ray diffraction patterns of the fibers show that PSmT ceramics have a pure perovskite structure. The c/a ratio of the unit cell was 1.04. The PSmT fiber/epoxy 1-3 composites were fabricated by filling the ceramic fiber bundle with epoxy. The dielectric permittivity ε, electromechanical coefficient k[sub t], and the piezoelectric constant d₃₃ of PSmT fiber/epoxy 1-3 composites with 68% fiber loading were 118, 0.51, and 48 pC/N, respectively. The hysteresis loop of the composites was measured by the Sawyer-Tower method. It was also found that the composites could withstand an electric field of 15 kV/mm at room temperature.