Abstract: Lead-free Na1/2Bi1/2TiO3-6BaTiO3 (BNT-6BT) ceramics with different dopants were prepared
by a conventional ceramic fabrication technique. The influence of doping CeO2, La2O3, Nb2O5 and Co2O3
on the structure was studied, and the mechanism of soft and hard additives with A-site or B-site substitute
changing the piezoelectric properties was discussed. It was found that the rhombohedral-tetragonal
morphotropic phase boundary (MPB) of the Na1/2Bi1/2TiO3-6BaTiO3 was not changed obviously.
Abstract: In this work, tape-casting technique was employed to prepare Ba0.7Sr0.3TiO3 films for lens
antenna system. Effects of slurry properties on the tape casting procedure were investigated and the
thickness, tensile strength and the surface roughness of the tapes were studied. The structure, morphology
and the dielectric properties of the films were analyzed.
Abstract: Pure barium strontium titanate (Ba0.65Sr0.35TiO3) and MnO2-modified barium strontium
titanate (Ba0.65Sr0.35TiO3-MnO2) thick films were fabricated by electrophoretic deposition technique. The
structures and morphologies of the films were analyzed. The dielectric measurements were conducted on
metal-insulator-metal capacitors using platinum as the bottom electrodes and gold as the top electrodes.
The dielectric constants and dissipation factors of Ba0.65Sr0.35TiO3 and Ba0.65Sr0.35TiO3-15wt% MnO2
thick films were measured at a frequency of 1 MHz. The tunabilities of 12.5% and 9.3% were obtained for
Ba0.65Sr0.35TiO3 and Ba0.65Sr0.35TiO3-MnO2 thick films under an applied electric field of 15 kV/cm,
respectively. The dielectric properties of the present thick films were suitable for tunable microwave
Abstract: The anti-reducing sintering of (Ca,Sr,Ba)TiO3-based dielectrics was achieved by the cooperating
effect of Mn2+, Ca2+, Mg2+, Dy3+ and Yb3+. A small quantity of Zr4+ partly substitution for Ti4+ can
improve the temperature dependence of dielectric constant. But ZrO2 will also reduce the solid solubility
of BaTiO3-SrTiO3-CaTiO3 ternary system, and may cause phase separation. The separated ferroelectric
phase increases the capacitance change under DC bias. Non-reducible (Ca,Sr,Ba)(Ti,Zr)O3-based dielectrics
with single orthorhombic phase of perovskite structure was obtained. The dielectric and DC bias
properties are: .C/C (DC bias: 1.5kV/mm) <0.05%, ε =250~300, tgδ < 0.5%.
Abstract: (PU/UP IPNs)-BaTiO3 nanocomposites with different amounts of BaTiO3 nanopowder are
prepared and polarized. The ferroelectric and dielectric properties are detected and the relationship
between electric properties and damping properties are discussed in detail. Results indicate that the
synergistic effects can be created successfully by elastic damping of polymer, frictional damping of
BaTiO3, and piezoelectric damping of nanocomposites after poling. The nanocomposites increase the
damping property evidently and sustain mostly ferroelectric and dielectric characters of inorganic phase.
The introduction of BaTiO3 into IPNs decreases the resistivity, and this has advantages to enlarge the
damping loss factor (tanδ).
Abstract: High <001>-textured Na1/2Bi1/2TiO3-BaTiO3 (6mol%BaTiO3) ceramics were fabricated by
reactive-templated grain growth (RTGG), using plate-like Bi4Ti3O14 particles prepared by a molten
salt method as the templates. The effect of template concentration on the texture development and
microstructure evolution was studied, and the mechanisms of grain orientation and densification were
also discussed. The design of Bi element reaction has important impact on the texture development.
Abstract: The phase composition of (1-x)BaO·xSrO·0.7TiO2·0.3Nb2O5 (BSTN) composite ceramics was
analyzed by XRD, and the effect of Sr/Ba ratio on the dielectric properties of BSTN was investigated by
impedance analyzer. The results showed that any sample with different x value contained two phases-the
perovskite phase and the tungsten bronze phase. The dielectric constants of BSTN basically decreased
while the tanδ increased with the increase in x value. Both dielectric constant and tanδ decreased with the
applied frequency increased for the same x value. There were two Curie points for BSTN composite
ceramics. The first one belonging to the perovskite phase decreased with the increase in x value, but the
second one belonging to the tungsten bronze phase kept almost constant at about 300°C.
thin films were deposited on Pt/Ti/Si(p-100) substrate by RF magnetron
sputtering at room temperature, and crystallized in a RTA furnace at temperature of 675°C for 10
minutes. SIMS analysis identifies that bismuth content in the Bi4Ti3O12 thin film reduced slightly
from the surface into a depth of approximately 200 nm. XRD patterns revealed (117) phase was
dominated regardless the film thickness, and the intensity of the other peaks increased with the
increase of film thickness. (200) peak became dominant when the thickness of films were greater than
680 nm. SEM observation showed that the grains were stripe plate-like, and the grain size increased
with the increase of film thickness. Dielectric constant increased with the increase of film thickness,
and kept around a certain value with the thickness ranging from 300 to 640 nm, then it rose again as
the film thickness above 680 nm. The leakage current and electrical breakdown also strongly
depended on the film thickness.
Abstract: Srm-3Bi4TimO3m+3 (m =3, 4, 5, and 6) bulk ceramics were prepared by conventional solid-state
reaction process. Their phase structures and morphologies were observed by XRD and SEM respectively.
The dielectric properties and hysteresis loops of the ceramics were measured by impedance analyzer and
hysteresis meter respectively. Results showed that the lattice parameters along the c axis are 32.79, 41.11,
48.83, and 58.17Ǻ for m=3, 4, 5, and 6 respectively. The microstructures of plate-like crystalline phases
are shown in all the ceramics with different m. Curie temperature of Srm-3Bi4TimO3m+3 decreases from
668°C to 295°C with increasing m from 3 to 6. The remnant polarizations Pr are 32.46 and 19.44 μC/cm2
for odd m of 3 and 5, and 11.84 and 10.58 μC/cm2 for even m of 4 and 6 respectively.
Abstract: The uniform Sr0.5Ba0.5Bi4Ti4O15 thin films were prepared using a modified Sol-Gel technique
and the influence of precursor on the microstructure and characterization of thin films were studied. The
stability and uniformity of precursor solution is key issue for the quality of thin films. Ethanolamine is an
effective complexation reagent of Bi3+, which could moderate the acidity of precursor. When pH value
and concentration of precursor solution was about 3.5 and 0.35M respectively, the smooth and uniform
Sr0.5Ba0.5Bi4Ti4O15 thin films could be obtained. The Bi-layered perovskite structure of
Sr0.5Ba0.5Bi4Ti4O15 formed at 750°C. The morphology of the grains in Sr0.5Ba0.5Bi4Ti4O15 thin films was
elliptoid and the grain size was about 90 ~ 100 nm.