共查询到20条相似文献,搜索用时 59 毫秒
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高性能环境友好型(K,Na)NbO3(KNN)基无铅压电陶瓷是国际上功能陶瓷的重要科学前沿和技术竞争焦点之一。优异的压电性能及其温度稳定性、抗疲劳特性、力学性能以及制备工艺重复性等综合性能是KNN基陶瓷有望得以广泛应用的重要前提,而这些性能与KNN基陶瓷的多层次结构紧密相关。本工作从多层次结构调控的角度出发,总结了KNN基陶瓷压电性能与其温度稳定性、抗疲劳特性、力学性能、制备工艺重复性研究等方面的研究进展以及KNN基陶瓷的应用技术研究进展。最后,就KNN基无铅压电陶瓷的未来发展进行展望。 相似文献
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利用固相法制备了K_(0.5)Na_(0.5)NbO_3(KNN)–x BiMg_(0.5)Ti_(0.5)O_3电介质陶瓷,研究了BiMg_(0.5)Ti_(0.5)O_3对KNN基陶瓷储能性质的影响。结果表明,当x0.1时,BiMg_(0.5)Ti_(0.5)O_3可完全固溶进入晶格,并且随着掺杂量的增加,晶体结构逐步由正交相变成厭立方相,晶粒尺寸降低,致密度提高,因此陶瓷的储能密度和储能效率逐步增加,在x=0.1时,获得最佳储能性能:击穿场强约195 kV/cm,储能密度约1.25 J/cm~3,储能效率约85.3%。 相似文献
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采用固相反应法制备了(1-x)Li0.05(K0.5Na0.5)0.95NbO3-x(Bi0.5Na0.5)TiO3(LKNN-BNT)无铅压电陶瓷,研究了BNT的添加量x(0,0.005,0.01,0.02)对LKNN-BNT陶瓷的结构与电性能影响。X射线衍射(XRD)分析结果表明当x≤0.005时,陶瓷为正交钙钛矿结构,而当x≥0.01时,陶瓷则转变为四方钙钛矿结构,说明该陶瓷的多型相转变(PPT)区域为0.005相似文献
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采用固相法制备了 Na0.5Bi0.5TiO3–K0.5Bi0.5TiO3–BaTiO3–SrTiO3(NBT–KBT–BT–ST)陶瓷,该体系是按(1–2x)(0.8NBT–0.2KBT)–x(0.94NBT–0.06BT)–x(0.74NBT–0.26ST) (x = 0.10、0.20、0.25、0.30、0.35、0.40、0.45)组合而成的,研究了该系陶瓷的结构与电性能。结果表明:所有样品都处于三方–四方准同型相界区域。该系陶瓷在准同型相界附近表现出了优异的压电性能,压电常数 d33、机电耦合系数 kp和剩余极化强度 Pr随 x 的增加先升高后降低,其中 x=0.35 陶瓷的电性能最佳:d33= 210 pC/N,kp= 0.319,Pr= 39.3 μC/cm2,Ec= 20.2 kV/cm,是一种良好的无铅压电陶瓷候选材料。依据准同型相界组成的线性组合规律来寻找具有优异压电性能的 NBT–KBT–BT–ST 陶瓷准同型相界组成是可行的。 相似文献
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Magnetoelectrics are materials that join magnetic and electric orderings in the same phase. They exhibit magnetoelectric coupling which is important from the fundamental and practical point of view. The subject of the paper is a presentation of magnetic, electric and magnetoelectric properties of 0.5BiFeO3–0.5Pb(Fe0.5Nb0.5)O3 solid solution. The obtained material belongs to oxide perovskite magnetoelectrics of relatively high magnetic and electric ordering temperatures. Both temperatures are considerably above room what suggests potential application possibilities of the material. The magnetic properties were investigated using Mössbauer spectroscopy and magnetization measurements. The solid solution is an antiferromagnet with incomplete compensated magnetic moments. The electrical properties were determined using impedance spectroscopy analysis. There is an observed change of the electrical properties at the magnetic ordering temperature what indicates magnetoelectric coupling in the system. The electrical conductivity mechanism is also proposed. Magnetoelectric voltage coefficient was determined and possible explanation of its changes was proposed. 相似文献
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A solid state metathesis approach has been applied to synthesize perovskite oxides such as BaTiO3, PbTiO3, K0.5Bi0.5TiO3 and Na0.5Bi0.5TiO3, these were characterized by powder XRD, IR and energy dispersive spectra (EDS). Potassium titanium oxalate and metal chlorides are used as the starting materials. X-ray analysis shows the formation of a single phase with tetragonal structure for BaTiO3, PbTiO3, K0.5Bi0.5TiO3 and a monoclinic structure for Na0.5Bi0.5TiO3. The Infrared spectra of these compounds show the characteristic band due to Ti–O octahedron for all the compounds. The EDS spectra show the relative ratio of the metal ions. The morphology of synthesized compounds was obtained from SEM measurements. 相似文献
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采用传统固相法制备了(Na0.8K0.2)0.5Bi0.5TiO3+xmol%Co3+(BNKT-xCo,x=0-8)无铅压电陶瓷,研究了Co2O3掺杂对BNKT陶瓷的显微结构与电学性能的影响。研究表明:适量的Co2O3掺杂促进了晶粒生长,纯BNKT陶瓷样品在介电温谱上有2个介电反常峰Td和Tm,Co2O3掺杂后使所有陶瓷样品的第一个介电反常峰Td消失,表明Co3+抑制铁电-反铁电相变。室温下样品的介电、铁电和压电性能表明Co2O3起硬性掺杂效应。当x=7时陶瓷样品电性能最佳,其中机械品质因子Qm=498,介电损耗tanδ=2.3%(1kHz),压电常数d33=103pC/N,平面机电耦合系数kp=27%。 相似文献
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Aurang Zeb Saeed ullah Jan Faith Bamiduro David A. Hall Steven J. Milne 《Journal of the European Ceramic Society》2018,38(4):1548-1555
Multiple ion substitutions to Na0.5Bi0.5TiO3 give rise to favourable dielectric properties over the technologically important temperature range ?55?°C to 300?°C. A relative permittivity, εr,?=?1300?±?15% was recorded, with low loss tangent, tanδ?≤?0.025, for temperatures from 310?°C to 0?°C, tanδ increasing to 0.05 at ?55?°C (1?kHz) in the targeted solid solution (1–x)[0.85Na0.5Bi0.5TiO3–0.15Ba0.8Ca0.2Ti1-yZryO3]–xNaNbO3: x?=?0.3, y?=?0.2. The εr-T plots for NaNbO3 contents x?<?0.2 exhibited a frequency-dependent inflection below the temperature of a broad dielectric peak. Higher levels of niobate substitution resulted in a single peak with frequency dispersion, typical of a normal relaxor ferroelectric. Experimental trends in properties suggest that the dielectric inflection is the true relaxor dielectric peak and appears as an inflection due to overlap with an independent broad dielectric peak. Process-related cation and oxygen vacancies and their possible contributions to dielectric properties are discussed. 相似文献
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Lead free piezoelectric Bi0.5(Na0.5K0.5)0.5TiO3 (pure and 1 wt.%, 2 wt.%, 4 wt.% Sb-doped) ceramics were synthesized away from its MPB. The crystalline nature of the BNKT ceramic was studied by XRD and SEM. Depolarization temperature (Td) and transition temperature (Tc) were observed through phase transitions in dielectric studies which were found to increase after Sb-doping, thus increasing its usable temperature range. In the study of relaxation behavior, the activation energy for relaxation was found to be 0.33, 0.43, 0.57 and 0.56 eV for pure and Sb-doped samples, respectively. All samples were found to exhibit normal Curie-Weiss law above their Tc. Doping of Sb was found to restrain the diffused character of the pure sample. In P-E loop, Sb-doping was found to increase the ferroelectric properties.Pure and Sb-doped BNKT ceramics exhibited high values of piezoelectric charge coefficient (d33) as 115, 121, 129 and 100 pC/N, respectively. 相似文献
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Sheng Liu Shuoqing Yan Heng Luo Longhui He Jun He Zhaowen Hu Shengxiang Huang Lianwen Deng 《Ceramics International》2018,44(4):3712-3717
In this paper, we investigated the effect of magnetic grain size on magnetoelectric responses of particulate magnetoelectric 0.7(Bi0.5Na0.5TiO3-Bi0.5K0.5TiO3)-0.3(Ni0.8Zn0.2)Fe2O4 (BNKT-NZFO) composites. The coexistence of two chemically separated phases was confirmed using x-ray diffraction analysis. The composites had homogeneous microstructure with controlled grain size. The magnetoelectric response of the BNKT-NZFO composites sensitively depended on the grain size of the NZFO phase and the magnetoelectric voltage coefficients presented a marked enhancement of 33% in the engineered grain size range. This result indicated that tailoring the magnetic grain size physically will provide a powerful mean of enhancing magnetoelectric coupling in a two-phase particulate composite, with large potential application in area of magnetic field sensor. 相似文献
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Ceramics with temperature-stable dielectric characteristics have been developed in the system: 0.6[0.85Na0.5Bi0.5TiO3-(0.15-x)Ba0.8Ca0.2TiO3-xBi(Mg0.5Ti0.5)O3]?0.4NaNbO3, x ≤ 0.15. Dielectric measurements exhibited relaxor ferroelectric characteristics with temperature-stable relative permittivity from εr~1330 ± 15% in the temperature range from ?70?°C to 215?°C and tanδ ≤ 0.02 from ?20?°C to 380?°C for x = 0 compositions. For the Bi(Mg0.5Ti0.5)O3 modified compositions the temperature range of stable relative permittivity extended from ?70?°C to 400?°C, with εr ~ 950 ± 15% and tanδ ≤ 0.02 from ?70?°C to 260?°C. Values of dc resistivity were ~ 108 Ω?m at a temperature of 300?°C and the corresponding RC constant values were in the range from 0.40 ? 0.78?s at 300?°C. All ceramic samples exhibited a linear polarisation-electric field response at maximum applied electric field of 5?kV/cm (1?kHz). 相似文献