Pseudoternary xBaTiO 3 -yCaTiO 3 -(12x2y)BaZrO 3 (BT-CT-BZ) lead free piezoelectric ceramics were prepared by the conventional solid state reaction method sintered at 1450-1510uC for 2 h. Sintering conditions, composition and polarisation conditions exert great influences on structure and electrical properties of the sintered BT-CT-BZ ceramics. The synthesised BT-CT-BZ ceramics exhibit rather large bulk density and densified microstructure morphology, although slight content of pyrochlore phase impurity exists. With increasing CaTiO 3 content, crystal structure of the BT-CT-BZ ceramics changes gradually from rhombohedral perovskite structure, across morphotropic phase boundary (MPB) composition and to tetragonal one. The dielectric response character changes successively from broad dielectric peaks to narrow ones accompanied by slight content of dielectric frequency dispersion, whereas the MPB effect is not apparent. The temperature of dielectric constant maximum T C increases almost linearly with increasing CaTiO 3 content. The BT-CT-BZ ceramics exhibit fully developed, saturated and symmetric polarisation-electric field P-E hysteresis loops, excellent piezoelectric property and perfect electromechanical resonance response peaks, in which the MPB effects are detected clearly by ferroelectric and piezoelectric properties measurements.
In order to improve the strength and plasticity of cold-rolled dual-phase DP980 steel, the relationship between process structure and properties were systematically studied by adjusting continuous annealing process parameters. The microstructure, recrystallized grains, phase distribution, and texture of different phases at different annealing temperatures were analyzed by OM, SEM, and EBSD. At the same time, the effect of continuous annealing temperature on the strength and plasticity were studied by mechanical tensile tests. The results obtained show that by optimizing and adjusting the continuous annealing process, not only a small amount of residual austenite can be obtained on the structure of cold rolled ferrite and martensite dual phase steel, but also recrystallized grains can be refined. Finally, cold-rolled DP980 steel with YS/TS < 0.5 and high elongation A50 < 15% can be obtained, and its strength/plasticity balance can be increased to 15-20 GPa%, which is also favorable for its formability.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.