论文标题
偶极对取代钛酸钡陶瓷的铁电相进化的介电和结构研究
Dielectric and structural studies of ferroelectric phase evolution in dipole pair substituted barium titanate ceramics
论文作者
论文摘要
BA {[GAX，税] Ti（1-2x）} O3陶瓷的X陶瓷等于0、0.0025、0.005、0.01、0.025和0.05，已通过常规的固态反应制备。已经进行了结构和介电表征，以研究偶极子取代浓度对宏观介电特性的影响。随着X的增加，ba {[Gax，税收] Ti（1-2x）} O3从经典的铁电转变为扩散相变（DPT）。 X> or = 0.01的BA {[GAX，税] ti（1-2x）} O3具有与Pb（MG1/3NB2/3）O3-PBTIO3（PMN-PT）相当的扩散参数（PMN-PT）（PMN-PT），最近报告并最近报道（BA0.97PR0.03）（BA0.97PR0.03）（TI0.9425CE0.0.0.0.0.05ce0.05ce0.05ce0.05ce05ce0.bpt） TM是严格定义的松弛剂铁电。此外，BA {[GA0.05，TA0.05] TI0.9} O3具有相对介电常数εr，在温度范围内的10 kHz下为10 kHz的耗散率为700 +/- 16％[-75°C，120°C]。与BATIO3相比，BA {[GAX，TAX] Ti（1-2x）} O3在室温下和更高的情况下具有增强的电阻率。已经进行了原位XRD，包括Rietveld改进，以确定温度范围内每个组合物的晶格参数，热膨胀系数和相变温度（TC）[RT，1000°C]，从而将介质特性与材料结构联系起来。这些研究通过温度依赖的拉曼光谱证实了这些研究，以比较通过电和结构表征确定的TC。 BA {[GAX，税] Ti（1-2x）} o3的特性与可用模型进行了讨论
Ba{[Gax,Tax]Ti(1-2x)}O3 ceramics with x equal to 0, 0.0025, 0.005, 0.01, 0.025 and 0.05 have been prepared by conventional solid-state reaction. Structural and dielectric characterization have been performed to investigate the effect of dipole-pair substitution concentration on the macroscopic dielectric properties. Ba{[Gax,Tax]Ti(1-2x)}O3 evolves from a classic ferroelectric to a diffuse phase transition (DPT) as x increases. Ba{[Gax,Tax]Ti(1-2x)}O3 for x > or = 0.01 possesses diffuseness parameters comparable to Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) and recently reported (Ba0.97Pr0.03)(Ti0.9425Ce0.05)O3 (BPTC), yet it lacks the frequency and temperature dependence of Tm necessary to be a strictly defined relaxor ferroelectric. Additionally, Ba{[Ga0.05,Ta0.05]Ti0.9}O3 possesses a relative permittivity, εr, of 700+/-16% and dissipation factor less than 0.05 at 10 kHz within the temperature range [-75°C, 120°C]. In comparison to BaTiO3, Ba{[Gax,Tax]Ti(1-2x)}O3 possesses enhanced electrical resistivity at and above room temperature. In-situ XRD, including Rietveld refinement, have been performed to determine the lattice parameter, coefficient of thermal expansion and phase transition temperature (Tc) of each composition within the temperature range [RT, 1000°C], thus linking the dielectric properties with the materials structure. These studies have been corroborated by temperature dependent Raman spectroscopy to compare the Tc determined by electrical and structural characterization. The properties of Ba{[Gax,Tax]Ti(1-2x)}O3 are discussed in context with available models that describe donor and acceptor dopants spatially separated in the parent matrix, inter-relating lattice parameter, Curie temperature, and other material properties
