共查询到17条相似文献,搜索用时 437 毫秒
1.
2.
3.
采用射频磁控溅射技术在Pt/Ti/SiO2/Si衬底制备了(Pb,La)TiO3(简记为PLT)铁电薄膜.利用XRD对PLT薄膜的结晶性能进行了研究.实验结果表明,在一定的制备工艺条件下,可以制备出完全钙钛相的PLT铁电薄膜.PLT铁电薄膜的结晶性能与溅射的工作气压、氧氩比、退火温度等关系密切;PFM表明PLT薄膜的电畴具有180°结构. 相似文献
4.
本文通过铌锌酸铅基复合钙钛矿结构铁电陶瓷的电畴观察、强场极化反转行为以及直流偏压下介电行为和X射线衍射峰等的详细测量,对铁电微畴、宏畴在外场诱导下的反转规律进行了分析,探讨了与铁电陶瓷介电行为相对应的微观极化机制。 相似文献
5.
研究了制作工艺对于反铁电陶瓷材料性能的影响,以及调压用PLZST在电场诱导下发生反铁电-铁电相变现象,对反铁电陶瓷在不同强度电场下所表现出的极化强度随电压变化进行了测试,记录结果表明,用于在持续电压作用下调压用反铁电陶瓷,对于处于反铁电-铁电开关电场附近(EAFE-FE)的电压波动调压效果最好.此时小电压波动能够引起较大范围内的极化强度值的变化,在此时对于能量的吸收作用最强.从而对于调压用反铁电陶瓷应根据陶瓷的电滞回线选择合适的调节范围. 相似文献
6.
7.
反铁电陶瓷材料在电场诱导下发生反铁电-铁电相变.为了研究快速电场诱导相变,诱导电场选择高压脉冲电源产生的脉冲电场.反铁电陶瓷选用Pb(Zr,Sn,Ti)O3相图中位于反铁电-铁电相界附近,正向相变电场小于40kV/cm的锆锡钛酸铅.脉冲电源输出波形为2.7 μs电压脉冲,测量陶瓷样品两端的电压波形与所通过的电流波形,作出正向半周期的"脉冲电滞回线".可以看到反铁电陶瓷在脉冲电场诱导下发生了相变. 相似文献
8.
9.
10.
11.
介绍了几种相转变韧化机制,主要包括ZrO2相变增韧、铁电/压电性畴转变增韧、铁弹性畴转变增韧的增韧机理和研究进展。提出一种新的相转变增韧机制——铁磁性畴转变增韧机制,即利用铁磁相的磁畴转变或压磁效应来实现能量耗散,从而达到增韧效果,探讨了其可能性。 相似文献
12.
Numerical analysis of ferroelectric/ferroelastic domain switching in ferroelectric ceramics 总被引:1,自引:0,他引:1
A numerical approach predicting the behavior of ferroelectric ceramics under electric field and mechanical loading is proposed in this paper. In the model, macroscopic properties of ferroelectric ceramics are determined by microscopic structures. Ferroelectric ceramics are seen to be composed of many domains with different orientations, and domain switching is the source of the nonlinear constitutive behavior of the ferroelectric ceramics. Numerical calculations based on the model were carried out, and the computational results are compared with the experimental results, which shows the two sets of results consist with each other. The calculation approach can provide a guidance for the ceramics component design. 相似文献
13.
14.
15.
The external electric and mechanical fields applied at angles to the initial poled direction of the ferroelectric ceramics produce a significantly different nonlinear behavior to that of external fields applied parallel to the poling direction. This angle dependent response of ferroelectric single and polycrystals are predicted by the model proposed based on irreversible thermodynamics and physics of domain switching. The dissipation associated with boundary constraints in thin ferroelectric single crystals are incorporated in the model. As well, the pressure dependent constraints imposed by the surrounding grains on the grain of interest at its boundary during domain switching is correlated with the resistance experienced by a ferroelectric single crystal on its boundary during domain switching. Taking all the domain switching possibilities, the volume fractions of each of the variants in a grain are tracked and homogenized for macroscopic behavior. Numerical simulations were carried out for the multiaxial behavior of ferroelectric single and polycrystals under electrical, mechanical and electromechanical loading conditions. 相似文献
16.
Lead zinc niobate (Pb(Zn1/3Nb2/3)O3, PZN) based ceramics are prepared by using conventional mixing oxide and complex phase reaction-sintering ceramic techniques. From the results of X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), it is clear that these two fabrication processing routes produce different microstructures and ferroelectric domains in the same Pb(Zn1/3Nb2/3)O3–BaTiO3–Pb(Zr0.4Ti0.6)O3 composition. Furthermore, different phase transitions are observed for the temperature dependence of the dielectric permittivity that can be confirmed by differential scanning calorimetry (DSC). Different polarization switching characteristics are also examined by using high field-induced strain and ferroelectric hysteresis loop. It is suggested that the distribution of the inner stress and domain configuration should be related with the fabrication processing of ferroelectric ceramics. 相似文献
17.
应用铁电体极化反转的Orihara Ishibashi理论 ,讨论了圆形铁电薄膜和球形铁电体的开关电流以及开关时间对系统尺寸的依赖性。数值计算表明 ,不论是二维还是三维铁电系统 ,其铁电畴反转过程中产生的开关电流都随系统尺寸减少而下降 ,开关时间随系统尺寸减少而缩短 相似文献