（Y—ZrO2）—SiCw—Al2O3陶瓷复合材料的摩擦磨损

本文对Ａｌ２Ｏ３基陶瓷复合材料Ａｌ２Ｏ３－ＺｒＯ２－ＳｉＣｗ进行了干摩擦磨损试验，并运用了ＳＥＭ，ＴＥＭ和ＸＲＤ等手段对其显微结构、力学性能及它们与ＧＣｒ１５钢对摩时的摩擦磨损行为进行了系统分析，在此基础上深入探讨了ＳｉＣ面增韧补强作用对复俣材料的摩擦磨损性能的影响。     

MgO—CoO—NiO氧敏材料的缺陷化学及电导特性 研究

本文用点缺陷理论分析了ＭｇＯ－ＣｏＯ－ＮｉＯ系氧敏材料的缺陷模型。并测量了ＭｇＯ－ＣｏＯ－ＮｉＯ材料的高温电导与氧分压的关系。在实验的基础上，研究了该材料的缺陷化学及电导特必一，对其禁带宽度及缺陷的热力学参数进行了理论估算。实验结果与理论分析吻合得较好。     

Mg—Mn—Fe—O系热敏电阻变B值特性的研究

Ｍｇ－Ｍｎ－Ｆｅ－Ｏ系热敏电阻经还原处理后，具有低Ｂ高阻电学特性，不同于一般的ＮＴＣ热敏电阻，其Ｂ值随温度增加呈较大幅度的连续性增加。研究了还原条件、材料组分及烧结温度对样品电特性的影响，解释了Ｍｇ－Ｍｎ－Ｆｅ－Ｏ系热敏电阻的变Ｂ值机理。     

过渡金属氧化物NTC厚膜热敏电阻烧结工艺的研究

较详细地研究了Ｃｏ－Ｍｎ－Ｏ，Ｃｏ－Ｍｎ－Ｎｉ－Ｏ，Ｍｎ－ＮｉＣｕ－Ｆｅ－Ｏ，Ｃｏ－Ｍｎ－Ｎｉ－Ｒｕ－Ｏ四种厚膜热敏电阻材料的烧结过程，确定了各材料的最佳烧结温度，较全面地测试了文中各材料系列厚膜热敏电阻的特性参数，给出了元件的热老化特性，电阻－温度特性，伏安特性，时间常数，耗散系数等。     

中国GRP／COM桥梁的研究与实践

基于近１０年ＧＲＰ／ＣＯＭ桥梁的研究与实践，本文对其行为特征，设计理论及技术经济价值进行了探讨。认为材料性能可设计及组合结构的优势，使ＧＲＰ／ＣＯＭ桥梁具有潜在的竞争力；研究和实践，展示了ＧＲＰ／ＣＯＭ桥梁诱人的前景。     

ZrO2—Al2O3—SiC系复相陶瓷材料的冲蚀磨损

本文对ＺｒＯ２增韧１０％ＳｉＣ／Ａｌ２Ｏ３基复合材料和ＳｉＣ颗粒弥散强化５％Ａｌ２Ｏ３／ＺｒＯ２基复合材料的冲蚀磨损的研究，实验表明：相变增韧有助于断裂韧性的改善，从而缓和了材料的高角冲蚀率；高弹模量的ＳｉＣ二相粒子引入后基体材料的硬度增加，提高了材料的抗低角磨损能力。显微结构（ＳＥＭ）分析表明，不同的冲蚀角度条件下材料表面的损伤行为和磨损微观机制也不相同，通过ＰＵＤ计算，定量表征材料的抗切向磨损     

TiO2和ZrO2在B2O3—MgO—SiO2系晶化过程中的作用

采用Ｘ射线衍射（ＸＲＤ），差热分析（ＤＴＡ），扫描电镜（ＳＥＭ）和红外光谱（ＩＲ）等手段研究了ＴｉＯ２和ＺｒＯ２对Ｂ２Ｏ３－ＭｇＯ－ＳｉＯ２渣中含硼组分晶化行为的影响，结果表明，ＴｉＯ２和ＺｒＯ２作为晶核剂加入后，促进分相，降低了晶化活化能，有利于含硼组分以２ＭｇＯ．Ｂ２Ｏ３和３ＭｇＯ．Ｂ２Ｏ３，析出，加入ＴｉＯ２改变了硼渣结构，产生更多有利于２ＭｇＯ．Ｂ２Ｏ３和３ＭｇＯ．Ｂ２Ｏ３析出的（Ｂ２Ｏ５     

MxLa1—xFeO3气敏材料的制备及表征

采用液相化学共沉淀法制备出ＭｘＬａ１－ｘ ＦｅＯ３气敏材料。利用ＸＲＤ、ＳＥＭ、ＴＥＭ、ＩＲ、ＤＴＡＴＧ等分析技术，对材料的物相组成，结构，形貌等方面进行了表征。研究了各种因素对材料导电特性的影响情况。     

氧化皮—碳钢电偶体系中MoO^2—4的缓蚀机理

研究了氧化皮－碳钢电偶体系中ＭｏＯ＾２－４的缓蚀效果，并通过碳钢阳极极化曲线和氧化皮阴极极化曲线分析了ＭｏＯ＾２－４手缓蚀机理。结果表明，ＭｏＯ＾２－４是通过强烈抑制氧化皮－碳钢电偶体系中碳钢的阳极极化过程而抑制碳钢腐蚀的，缓蚀效果很好；碳钢的表面状况对ＭｏＯ＾２－４的作用效果有很大影响。     

溶胶—凝胶法制备WO3—SiO2材料的氨敏特性研究

采用溶胶－凝胶法制备了ＷＯ３＋ｘｗｔ％ＳｉＯ２（ｘ＝０，５，１０，２０）粉体材料。对其结构、形貌进行了ＸＲＤ、ＡＦＭ、ＸＰＳ和比表面积测量、分析，结果表明：获得了单斜晶系结构的ＷＯ３多晶材料；晶粒尺寸随ＳｉＯ２含量的增加而减小。测量了材料的ＮＨ３气敏特性，得到敏感元件的电阻和灵敏度随ＳｉＯ２含量的增加而增加；溶胶－凝胶法制备的ＷＯ３＋５ｗｔ％ＳｉＯ２粉料用于ＮＨ３测量具有优良的特性，在３５０℃及以上应用优于纯ＷＯ３材料。     

复相弛豫铁电陶瓷的相组成与介电性能

采用两相混合烧结法在Pb（Zn1／3Nb2／3）O3－BaTiO3－PbTiO3系统中制备了弛豫铁电陶瓷材料．相组成研究表明，该陶瓷具有两相共存的复相结构．对复相陶瓷的介电性能进行了研究，结果表明，复相结构可有效地改善弛豫铁电陶瓷的介温特性、频率特性和介质老化性能．     

Harmonic analysis of the polarization response in Pb(Mg(1/3 )Nb(2/3))O(3)-based ceramics-A study in aging

The polarization response of a ferroelectric ceramic displays nonlinear behavior at high applied fields due to saturation effects. Weak-field dielectric aging imposes additional nonlinearity on the hysteresis loops of these materials. Harmonic analysis using a discrete Fourier transform (DFT) permitted an observation of the change in the polarization frequency spectrum as Pb(Mg(1/3)Nb(2/3))O (3)-based relaxor ceramics aged. It also facilitated the calculation of ac current, power, and "internal bias field". The results show that particular harmonics in the polarization signal are sensitive indications of aging behavior. The average power dissipated at weak ac fields was found to decrease with aging time; and the power dissipated at strong fields tended to increase.     

PZN—BT系统的相变温度与纳米结构

由两个铁电体所组成的固溶体的平均相变温度通常都处于这两个铁电体的相变温度之间．然而，Ｐｈ（Ｚｎ１／３Ｎｂ２／３）Ｏ３－ＢａＴｉＯ３（ＰＺＮ－ＢＴ）的平均相变温度却呈现出明显不同的变化规律．随着ＢＴ含量的增加，ＰＺＮ－ＢＴ的平均相变温度迅速下降．本文从化学组成复杂的系统中存在着纳米分相的假设出发，提出在ＰＺＮ－ＢＴ系统中存在着以Ｂａ（Ｚｎ１／３Ｎｂ２／３）Ｏ３为主的顺电微区．采用热力学的方法，解释了ＰＺＮ－ＢＴ系统的相变温度的反常下降．     

Nonlinear dielectric response of AgNb(1-x)Ta(x)O3 in the vicinity of diffuse phase transitions

Linear and nonlinear dielectric studies of AgNb(1-x)Ta(x)O(3) (ATN) ceramics (x ≤ 0.6) were carried out in the temperature range of 80 to 673K. The temperature dependences of third-order nonlinear electric susceptibility X3'(T) exhibit two distinct maxima: at the temperature of the weak ferroelectric phase appearance, M(1)-M(2) transition, and at the temperature of the Nb/Ta ion dynamics freezing, Tf. For AgNbO3, they appear at 325K and 448K, respectively. With increasing Ta concentration, both maxima shift toward lower temperature: 4K/%Ta (M(1)-M(2)) and 5.6K/%Ta (T(f)). The X3' (T) maxima indicate changes of the Nb/Ta ion dynamics and their contribution to electric susceptibility. At T(f), a partial freezing of the Nb/Ta ion displacements to the disordered antipolar, antiferroelectric array takes place. At the M(1)-M(2) transition, further freezing of Nb/Ta displacements to polar weak relaxor ferroelectric or dipolar glass transition occurs. This polar state coexists with the ground antiferroelectric state. Studies of the aging process showed that below T(f) the aging influence on electric susceptibility is substantial, whereas above Tf it may be neglected. This means that for ATN ceramics in the concentration range used for applications, there is no aging process in the room temperature region, which is an additional advantage of this system.     

Thin film ferroelectrics for capacitor applications

Pulsed laser deposition (PLD) has been used to fabricate simple thin film capacitor structures with a variety of ferroelectric materials. Thin film capacitors using the conventional ferroelectric material BaxSr1-xTiO3(BSTO) have been made across the entire compositional series. Electrical characterization shows that in thin film form these ferroelectrics display Curie point behaviour which is largely independent of composition. This contrasts sharply with bulk behaviour. The thin film fabrication and characterization of relaxor ferroelectric ceramics, such as Pb(Mg1/3Nb2/3)O3 (PMN) and Pb(Zn1/3Nb2/3)O3-BaTiO3(PZN-BT), is also reported. © 1998 Chapman & Hall     

Investigation on the fabrication and properties of Ce-doped PMN–PT translucent piezoelectric ceramics

Journal of Materials Science: Materials in Electronics - Relaxor ferroelectric ceramics (1–x)Pb(Mg1/3Nb2/3)O3–xPbTiO3 (PMN–PT) at the morphotropic phase boundary exhibit high...     

Nb掺杂Bi4Ti3O12层状结构铁电陶瓷的电行为特性研究

采用固相烧结工艺制备了Nb⁵⁺掺杂的Bi₄Ti₃O₁₂层状结构铁电陶瓷.运用XRD 和AFM对Bi₄Ti_3-xNb_xO_12+x/2材料的微观结构进行表征,发现所制备的陶瓷均具有单一的正交相结构,抛光热腐蚀表面晶粒的显微形貌表现为随机排列的棒状结构.通过对材料直流电导率与温度关系的Arrhenius拟合,分析丁Bi₄Ti_3-xNb_xO_12+x/2的导电机理. Nb⁵⁺掺杂提高了材料的介电常数,但居里温度随掺杂含量的增加呈线性下降趋势.DSC结果显示Bi₄Ti_3-xNb_xO_12+x/2材料在居里温度处经历了一级铁电相变.样品的铁电性能测试结果表明, Nb⁵⁺掺杂Bi₄Ti₃O₁₂提高了材料的剩余极化Pr,这主要是由于^_Nb5+取代Ti⁴⁺大大降低了材料中氧空位的浓度,使得氧空位对畴的钉扎作用减弱的缘故.     

Relaxor behavior in Ba(Zn1/3Nb2/3)O3-PbTiO3 new solid solution

Relaxor behavior has been found in a new solid solution between complex perovskite Ba(Zn(1/3)Nb(2/3))O(3) (BZN) and ferroelectric PbTiO(3) (PT), prepared by solid state reactions. A strong dispersion of the maximum of dielectric permittivity (epsilon(')) appears around the temperature of T(m), which shifts toward higher temperatures with increasing frequency. The variation of T(m) with frequency follows the Vogel-Fulcher relationship. The variation of 1/epsilon(') with temperature above Tm deviates from the Curie-Weiss law, but satisfies a Lorentz-type function. The relaxor behavior becomes weaker upon increasing PT-content.     

{110}cub切型Pb(Mg1/3Nb2/3)O3-PbTiO3单晶铁电相变的研究

测试了PMNT68／32{110}cub切型单晶的介电、压电性能和电滞回线，发现单晶铁电性能与所施加的极化电场及单晶中PbTiO3含量的变化密切相关。研究结果表明，相结构的变化是引起铁电性能变化的主要原因，即在＜110＞取向施加电场诱导出来的正交相是本征亚稳的，它的稳定性不仅取决于所施加的极化电场大小，而且与单晶中PbTiO3含量的变化密切相关。     

Pyroelectric performances of rhombohedral 0.42Pb(In₁/₂)Nb₁/₂)O₃-0.3Pb(Mg₁/₃Nb₂/₃)O₃-0.28PbTiO₃ single crystals

Relaxor-based ferroelectric single crystals xPb(In?/?)Nb?/?)O?-yPb(Mg?/?Nb?/?)O?-(1-x-y)PbTiO? {PIMNT [100x/100y/100(1-x-y)]} have been grown by a modified Bridgman technique. The as-grown PIMNT (42/30/28) crystal with rhombohedral perovskite-type structure shows higher Curie temperature TC ~ 187 °C, and higher ferroelectric rhombohedral-to-tetragonal phase transition temperature TRT ~ 152 °C, both about 50 °C higher than those found for 0.71Pb(In?/?)Nb?/?)O?-0.3Pb(Mg?/?Nb?/?)O?-0.29PbTiO? crystals. Moreover, as a core parameter of pyroelectric material, the detectivity figures-of-merit of PIMNT (42/30/28) crystal are higher than other typical relaxor-based ferroelectric crystals, which primarily stems from the lower dielectric loss, making it promising candidate for infrared detector applications.