陶瓷现代成型技术的研究进展

分析了成型工艺在陶瓷制备中的重要作用和高质量的陶瓷坯体对成型工艺的基本要求，评述了国内外陶瓷现代成型技术，着重介绍了离心沉积成型、电泳沉积成型、离心注浆成型、注射成型、胶态成型和快速自动成型等新工艺，讨论了上述成型方法的基本原理和特点，指出了陶瓷成型技术的发展思路。     

电泳沉积原理及其在陶瓷制备中的应用

本文介绍了电泳沉积(EPD)的原理,从胶体悬浮体系的DLVO经典静电稳定理论出发讨论了EPD的机理,综述了国外关于电泳沉积应用于陶瓷(包括传统瓷、技术瓷、超导瓷、生物瓷和复合瓷)坯体直接成型的研究进展。     

金属表面电泳法制备陶瓷涂层的研究进展

陶瓷涂层具有耐磨、耐蚀、耐高温和抗微生物侵蚀等性能。介绍了国内外用电泳沉积法制备生物陶瓷涂层、碳化硅陶瓷涂层、氧化钛陶瓷涂层、氧化铝陶瓷涂层、氧化硅陶瓷涂层及氧化锆陶瓷涂层的研究进展,揭示了防腐领域中陶瓷涂层存在的问题,提出了解决方法并展望了未来的研究方向。     

应用电泳沉积技术制备钛酸钡铁电陶瓷薄膜

采用电泳沉积技术在Pt电极基片上制备BaTiO3铁电陶瓷薄膜，探讨了电泳沉积过程中的控制因素（悬浮液体系，电场强度，料浆浓度，沉积时间等）对成膜性能的影响，并对薄膜材料的结构，性能进行了表征，实验结果表明；在1050℃（2h)的烧成温度下，经重复沉积一烧结2-3次可得到基本无缺陷的BaTiO3陶瓷薄膜，测量频率在1kHz，测量频率在1kHz时，室温（23℃）下的介电常数ε=2300，介电损耗tanδ=0.2。     

电化学方法制备磷酸钙生物陶瓷镀层

电化学方法是制备磷酸钙生物陶瓷镀层的重要方法之一,具有其它方法无可比拟的优点。基于电化学原理有三种技术可用于制备生物活性陶瓷镀层一电沉积技术、电化学复合共沉积技术和电泳沉积技术。本文对这三种技术用于制备磷酸钙生物陶瓷镀层的原理、特点及应用作了评述。     

日本高技术陶瓷的近况

高技术陶瓷是９０年代人们所注目的功能材料和工程材料，是继金属塑料之后的第三大类的材料体系，常为多晶烧结体，也包括单晶，薄膜或纤维结构，本文介绍了日本高技术陶瓷的产业群，功能陶瓷技术，工程陶瓷技术以及它们的应用技术。     

陶瓷FDM快速成形技术的应用

数字技术和快速成形技术在陶瓷生产中的应用越来越广泛,快速成形技术可用于设计方案验证、快速制模、快速制造等。本文阐述了数字技术和快速成形技术在陶瓷设计中的应用特点,并以熔融沉积快速成形为例,阐述了数字技术和快速成形技术在陶瓷设计中的应用过程,并运用一个典型的应用实例加以分析说明。     

电泳沉积法制备PZT压电陶瓷管

应用电泳沉积技术从乙醇悬浮液中制备出(壁厚约0.4mm,内径为0.8～2.4mm)锆钛酸铅[Pb(Zr0.52Ti0.48)O3,PZT]压电陶瓷管.分析了电泳沉积速率和ζ-电位对PZT悬浮液的稳定性及电泳沉积质量的影响,并研究了烧结前后PZT管的微结构和电学性能.实验结果表明,在pH为5.5～6.5范围,悬浮液的ζ-电位高达50mV以上,此时悬浮液体系分散好而稳定,有最佳的沉积速率和相对沉积密度.在此条件下制备出的PZT管,壁厚均匀一致,经1150℃烧结1h后,相对密度为98.7%,管直且基本无变形,剩余极化强度是29.7μC/cm2,矫顽场强是19.2kV/cm.     

特种陶瓷发展现状

1 前言特种陶瓷是采用“高度精选过的原料粉末”，通过“精确调整过的化学组成”和“精心控制的成形方法和烧成方法”合成的陶瓷，它是现代工业技术飞速发展的产物，是有别于传统陶瓷的一种新型陶瓷的总称。世界各国以及国内业界人士对特种陶瓷的称谓不一，说法众多，有称“工业陶瓷”、有称“现代陶瓷”、有称“精细陶瓷”、有称“高级陶瓷”和“高技术陶瓷”，也有称“先进陶瓷”。特种陶瓷一般可分为结构陶瓷和功能陶瓷。功能陶瓷具有特殊的电、磁、热、光等性能。结构陶瓷则具有耐高温、耐腐蚀、耐磨损和化学性质稳定等特点。由于特种陶…     

应用广泛的特种陶瓷

近几十年来，陶瓷工作者利用X射线衍射、扫描电镜和透射电镜等分析手段，以及量子理论和断裂力学等理论知识，使人们对陶瓷结构加深了了解，对传统陶瓷这个概念就发生了巨大的变化，而从陶瓷结构和功能上扩大陶瓷的使用范围，研究对象也开始打破陶瓷行业的界限，为了与传统陶瓷进行区别，人们将新的目标放在了它的结构和功能上，并命名为“特种陶瓷”，它包括两大类，即结构陶瓷和功能陶瓷。     

Electrophoretic fabrication of thermal barrier coatings

An electrochemical method of fabrication of (NiCoCrAlY)/MgO/yttria-stabilized zirconia (YSZ) multilayered coating was proposed. This multilayered coat is expected to work as a thermal barrier coating for nickel superalloy substrates. The (NiCoCrAlY) layer was deposited using the electrophoretic deposition technique, the MgO layer was deposited by the electrolytic deposition technique and the YSZ layer was electrophoretically deposited. The process of depositing (NiCoCrAlY) alloy particles revealed that the electrophoretic technique can be used for particles with submicron dimensions. The MgO intermediate layer was introduced to accommodate the difference in thermal expansion coefficient between the YSZ ceramic and the NiCoCrAlY metal layers.     

Elektrophoretische Abscheidung zur Herstellung von faserverstärkten Keramik‐ und Glasmatrix‐Verbundwerkstoffen — Eine Übersicht

In this paper, we review the application of the electrophoretic deposition (EPD) technique in the fabrication of fibre reinforced composites, with particular emphasis on composites with glass and ceramic matrices containing metallic or ceramic fibre fabric reinforcement. The review covers research published in the last 10 years. EPD has been used to infiltrate preforms with tight fibre weave architectures using different nano‐sized ceramic particles, including silica and boehmite sols, as well as dual‐component sols of mullite composition. The principles of the EPD technique are briefly explained and various factors affecting the EPD behaviour of ceramic sols and their optimisation to obtain high infiltration of the fibre preforms are considered. Overall, the analysis of the published data and our own results demonstrate that EPD, being simple and inexpensive, provides an attractive alternative for ceramic infiltration and coating of fiber fabrics, even if they exhibit tight fibre weave architectures.     

电泳沉积羟基磷灰石生物陶瓷涂层的研究进展

羟基磷灰石(hydroxyapatite，HAP)生物陶瓷涂层被认为是目前最好的用于替代人体硬组织的一种生物医用材料。电泳沉积是一种全新的涂层制备方法，它可以解决传统HAP生物陶瓷涂层制备工艺上的各种不足。文中综合介绍了国内外有关电泳沉积HAP生物陶瓷涂层的研究报道，概述了电泳沉积的工艺流程和工艺参数，并对各种影响因素全面地进行了详细的探讨，进而提出了相应的设想和展望。     

Electrophoretic deposition of ceramic coatings on ceramic composite substrates

Abstract

The applicability of electrophoretic deposition (EPD) for the fabrication of single layer and multilayer ceramic coatings on dense ceramic composite materials has been examined. Al₂O₃/Y-tetragonal zirconia polycrystal (TZP) functionally graded composites of tubular shape were successfully coated with a two layer coating comprising porous alumina and dense reaction bonded mullite layers. The dual layer coating structure was designed to eliminate the numerous cracks caused by volume shrinkage during sintering of the individual EPD formed layers. In another example, mullite fibre reinforced mullite matrix composites were coated with a thin layer of nanosized silica particles using EPD. The aim was to achieve a compressive residual stress field in the silica layer on cooling from sintering temperature, in order to increase composite fracture strength and toughness. The EPD technique proved to be a reliable method for rapid preparation of single layer and multilayer ceramic coatings with reproducible thickness and microstructure on ceramic composite substrates.     

Conductive Polymer Coating on Nonconductive Ceramic Substrates for Use in the Electrophoretic Deposition Process

Uniform coating and line patterning of a conductive polypyrrole (Ppy) film on nonconductive ceramic materials were performed for use as substrates in the electrophoretic deposition (EPD) process. The Ppy was synthesized by chemical oxidation in the pyrrole solution. Direct shaping or line patterning of alumina or zirconia particles by EPD was carried out using the Ppy films as cathodes.     

Investigation of properties of electric arc ion deposited TiN coating on Al2O3-based ceramic composite

Electric arc ion deposition technique was adopted to deposit TiN coating on Al2O3-based ceramic composite. Scanning electron microscopy and secondary ion mass spectrometry were used to analyze the microstructure, phase constitution, and quality of the TiN coating and the interface. Surface roughness and micro-hardness of the TiN coating were measured to evaluate its quality. Flexural strength of ceramic materials is dependent on both their inherent resistance to fracture and the presence of defects, thus it was used to investigate the effect of electric arc ion deposition technique on the surface modification of Al₂O₃-based ceramic composite. Experimental results show that the higher the deposition bias voltage, the better the coating quality. The TiN coating is homogeneous, with a uniform surface, and free of defects when the deposition bias voltage is 300 V. The TiN coating strongly adheres to the Al₂O₃-based ceramic composite, and the observed elemental interface diffusion strengthens the interface bonding.     

Electrophoretic deposition for fabrication of ceramic microparts

Electrophoretic deposition (EPD) is mostly used for producing moulds and layers. The present work shows the fabrication of ceramic microparts by the use of structured electrodes. As electrode structures euro coins and spinning nozzles were used. Additionally a cost effective and simple method was developed, which allows preserving the original master mould by using microstructured silicone moulds as substrate. This was enabled by coating the silicone moulds with graphite to obtain an electrically conductive surface, required for electrophoretic deposition.     

Electrophoretic deposition of carbon nanotube–ceramic nanocomposites

The purpose of this paper is to present an up-to-date comprehensive overview of current research progress in the development of carbon nanotube (CNT)–ceramic nanocomposites by electrophoretic deposition (EPD). Micron-sized and nanoscale ceramic particles have been combined with CNTs, both multiwalled and single-walled, using EPD for a variety of functional, structural and biomedical applications. Systems reviewed include SiO₂/CNT, TiO₂/CNT, MnO₂/CNT, Fe₃O₄/CNT, hydroxyapatite (HA)/CNT and bioactive glass/CNT. EPD has been shown to be a very convenient method to manipulate and arrange CNTs from well dispersed suspensions onto conductive substrates. CNT–ceramic composite layers of thickness in the range <1–50 μm have been produced. Sequential EPD of layered nanocomposites as well as electrophoretic co-deposition from diphasic suspensions have been investigated. A critical step for the success of EPD is the prior functionalization of CNTs, usually by their treatment in acid solutions, in order to create functional groups on CNT surfaces so that they can be dispersed uniformly in solvents, for example water or organic media. The preparation and characterisation of stable CNT and CNT/ceramic particle suspensions as well as relevant EPD mechanisms are discussed. Key processing stages, including functionalization of CNTs, tailoring zeta potential of CNTs and ceramic particles in suspension as well as specific EPD parameters, such as deposition voltage and time, are discussed in terms of their influence on the quality of the developed CNT/ceramic nanocomposites. The analysis of the literature confirms that EPD is the technique of choice for the development of complex CNT–ceramic nanocomposite layers and coatings of high structural homogeneity and reproducible properties. Potential and realised applications of the resulting CNT–ceramic composite coatings are highlighted, including fuel cell and supercapacitor electrodes, field emission devices, bioelectrodes, photocatalytic films, sensors as well as a wide range of functional, structural and bioactive coatings.     

Electrophoretic deposition of electroless nickel coated YSZ core-shell nanoparticles on a nickel based superalloy

In this work, yttria-stabilized zirconia (YSZ) nanoparticles were covered by a thin Ni layer with approximately 10 nm thickness by electroless deposition method to reduce sintering temperature of the ceramic coating which was applied on a Ni based superalloy via electrophoretic deposition (EPD). Suspensions containing the processed Ni-YSZ core-shell nanoparticles in acetone and isopropyl alcohol solvents were stabilized by addition of 0.4 wt% iodine and 1.5 wt% polyethylenimine, respectively, to find more effective stabilization method for EPD. It was seen that the presence of the Ni layer on YSZ nanoparticles improved performance and sticking factor of EPD and uniform coatings were obtained in both suspensions. The Ni-YSZ green coating which was produced by EPD at voltage of 35 V and deposition time of 30 min in acetone with thickness of 41 μm was sintered in 1100 °C and finally a uniform NiO-YSZ coating was formed on the metallic surface.     

A study of the electrophoretic deposition of bioactive glass-chitosan composite coating

Bioactive glass is coated on implant's surface to improve corrosion resistance and osseointegration, when placed in the body. Bioactive glass particles were synthesized through a sol-gel process and deposited along with chitosan to form a composite coating on a stainless steel substrate using electrophoretic deposition technique. Stable suspensions of chitosan-bioactive glass were prepared using bioactive glass particles (<1 μm) and 0.5 g/l chitosan solution. The influence of ethanol-water ratio on deposition yield was investigated. For all process conditions, best results were achieved with suspension of 30 vol% water in ethanol-water containing 2 g/l bioactive glass. FTIR studies showed that chitosan was absorbed on ceramic particle surface via hydroxyl and amid bonds. In order to evaluate the coating, its structure and electrochemical properties were studied. It was concluded that increasing the process voltage led to an increase in particle size and porosity, but induced cracks in the coating. In the presence of the polymer-bioactive glass coating, current density in artificial saliva was decreased by 52% and corrosion potential shifted toward more noble values.