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。     

浅析工程陶瓷的高效磨削技术

陶瓷具有高硬度和高脆性,机械加工后易产生各种类型的表面或亚表面损伤,导致陶瓷零件强度降低。为保持陶瓷零件表面完整性和尺寸精度,降低加工成本,本文从陶瓷磨削机理,浅析不同磨削工艺条件下选择合理的磨削参数以达到陶瓷高效磨削,介绍高速超高速磨削、深切缓进给磨削、ELID在线修整磨削等几种工程陶瓷的高效磨削加工技术及特点。     

可加工陶瓷材料的机械加工技术

介绍云母玻璃陶瓷、氧化物陶瓷和非氧化物陶瓷3类可加工陶瓷材料的显微结构特性与材料可加工性的关系，层片状结构与弱界面使陶瓷材料具备可加工性。分析了可加工陶瓷材料机械加工过程中的特性；适宜的加工工艺参数、低加工损伤及材料的沿晶界断裂模式。结合金属材料的可加工性研究，讨论了适于陶瓷材料可加工性评价的研究方法。     

特种陶瓷零件结构设计研究

设计特种陶瓷零件结构时，必须考虑成型、干燥、烧成及后加工等工艺过程的要求。本文论述了满足上述要求的陶瓷零件结构设计的基本原则，并通过示例进行了详细说明。     

基于挤出工艺的陶瓷零件增材制造及其关键技术

增材制造技术可以直接从CAD模型得到实体零件,无需加工刀具和模具,非常适合于结构复杂陶瓷零件的个性化、差异化制造。基于浆料或者膏体挤出而开发的陶瓷零件增材制造技术实用灵活,工艺方法也最多。本文主要阐述了基于挤出技术的增材制造技术的技术原理和特点,并对其中涉及的挤出材料、挤出方式和工艺控制等关键技术进行了综述。     

浅析陶瓷刀具高速切削可靠性的影响因素

简要介绍了影响陶瓷刀具高速切削可靠性的几种因素，阐明了陶瓷刀具与被加工材料的匹配性要求和陶瓷刀具几何角度的选择，以充分发挥陶瓷刀具的工效高、使用寿命长和加工质量好等优点。     

陶瓷轴承的特性与制造

对工程陶瓷，轴承钢等材料的重要性能进行了对比分析，对陶瓷轴承的生产工艺，检测手段，应用前景进行了介绍，论证了将工程陶瓷用于轴承制造的可行性和重要性。     

陶瓷与陶瓷或金属的接合

目前随着工业的发展,要求精密陶瓷、金属、金属陶瓷、有机材料等的性能优缺点互相补充利用,或由于制品形状的特殊需要,因此接合的应用日趋广泛,技术水平不断提高。近30年来陶瓷零件的接合有以下倾向:①批量小而品种多的类别增加;②小型零件的接合增加;③提高陶瓷纯度;④试制非氧化系陶瓷接合零件增加;⑤高温中使用的接合件要求     

计算机仿真技术在工程陶瓷加工技术中的应用

工程陶瓷作为一种高性能的材料,具有优异的力学、热学和化学性能,广泛应用于航空航天、汽车、生物医学等领域。然而,由于其脆性大、易开裂等特性,加工难度较大,因此需要借助计算机仿真技术对陶瓷加工过程进行模拟和优化。计算机仿真技术的引入,可提高产品质量和生产效率,降低生产成本和废品率。因此本文对工程陶瓷加工中计算机仿真技术的相关应用展开了探讨分析,以供参考。     

氮化硅反应烧结的研究进展

氮化硅作为高温功能陶瓷性能优越，但将其制备成陶瓷零件比较困难，目前一般用反应烧结法制备氮化硅陶瓷零件。此外，反应烧结制备氮化硅陶瓷还具有成本低、烧结温度低、产品成型好、陶瓷高温性能好等优点。综述了氮化硅陶瓷反应烧结工艺流程和工艺的优缺点，着重介绍了氮化硅反应烧结在成型工艺、烧结工艺、原材料影响、后处理和陶瓷增韧等方面所取得的进展。     

新型陶瓷刀具材料的研究与开发

工业用钢材的质量提高使材料加工难度增加,耐高温的高硬度高强度陶瓷材料被用做切削刀具并逐渐推广应用。本文对陶瓷刀具的材质、种类、性能特点作了比较和评价,并重点介绍了新型的晶须增韧陶瓷刀具。最后,对陶瓷刀具的市场前景进行了预测,并指出了陶瓷刀具研制方面应该深入研究的课题。     

Development of Silicon Nitride‐Based Ceramic Radomes — A Review

Radome is an aerodynamic structural part attached to the fore‐end of a missile. It transmits electromagnetic signals with minimum attenuation and also protects radar communication system, and thus, the radomes are made of ceramics as they have desirable properties required by the radomes. The flexural strength, dielectric constant, and loss tangent values of various ceramic materials used in the development of radomes are important in the selection of radome materials. Different nose cone shapes of missile radomes are also important. Ceramic materials show variational properties with sintering time, temperature, and other additives. The existing different near‐net shape fabrication techniques for manufacturing of ceramic radomes are discussed and compared. Gelcasting is one of the manufacturing techniques to produce radomes with homogeneous and high green strength. Gelcast parts of silicon nitride ceramics are hard, tough, brittle, and wear‐resistant and are difficult to machine using conventional methods of machining. Therefore, laser‐assisted machining is used for fine finish of ceramic radomes with excellent surface integrity and productivity. This paper deals with a review of development of ceramic radomes, manufacturing methods for variety of applications.     

A comprehensive review of electric discharge machining of advanced ceramics

Advanced ceramics are widely used in high temperature and wear related situations due to their unique physical and chemical characteristics. With the increasing demand for ceramics, the machining techniques of ceramics become a hot and tough issue because ceramics are extremely fragile and difficult to process. Traditional mechanical machining techniques like milling, turning, and drilling are subjected to large cutting forces and heat leading to extensive tool wear and poor machining performance. Electric discharge machining (EDM) has an outstanding ability of no-contact machining brittle and hardness materials with complex shapes via generating extreme high-temperature plasma channel to melt and vaporize materials. Therefore, in this paper, the research trends of latest EDM technologies for advanced ceramic materials were comprehensively reviewed. Firstly, according to the electrical conductivity of advanced ceramics, different EDM processes were introduced in details. Secondly, the existing physical models and material removal mechanisms of EDM process of ceramics were compared and analyzed. Then the machining performance indicators, such as MRR, Ra, TWR, surface topography, and micro-structures, were respectively investigated. Additionally, the new hybrid machining techniques of EDM were presented to provide some potential for efficiently machining advanced ceramics. Eventually, this paper also discussed the challenges associated with electrical discharge machining of advanced ceramic materials, and suggested some related research areas which possibly attract significant research attentions in the future.     

导电Al2O3基陶瓷刀具材料的超声—放电复合加工技术研究

采用超声－放电复合加工技术对Ａｌ２Ｏ３／（Ｗ,Ｔｉ）Ｃ,Ａｌ２Ｏ３／ＴｉＢ２,Ａｌ２Ｏ３／ＴｉＢ２／ＳｉＣｗ三种Ａｌ２Ｏ３基陶瓷刀具材料表面定位方孔进行加工,研究了共加工机理和加工参数对不同陶瓷材料加工效率,加工表面粗糙度的影响,由于该复合加工技术有产地结合了超扬波加工和放电加工的特点,因而能高效,高质量地加工陶瓷材料。试验结果表明,在同样的加工条件下,材料去除率的大小顺序为Ａｌ２Ｏ３／（Ｗ,Ｔｉ     

A review on machining of carbon fiber reinforced ceramic matrix composites

Carbon fiber reinforced ceramic matrix ceramic/polymers composites have excellent physical-mechanical properties for their specific strength, high hardness, and strong fracture toughness relative to their matrix, and they also possess a good performance of wear resistance, heat resistance, dimensional stability, and ablation resistance. It is a choice for thermal protection and high temperature structural materials. However, this kind of composites owning characteristics of high hardness and abrasion is difficult to machine which impedes the large-scale industrial application of manufacturing. This paper mainly reviews the research on machining status of carbon fiber reinforced ceramic matrix composites including carbon fiber reinforced polymer matrix composites from the aspects of conventional machining and unconventional machining method. The machining trends, problems existing in various machining methods and corresponding solutions are generalized and analyzed.     

工业陶瓷超声辅助加工技术研究

陶瓷材料具有耐高温、硬度高、绝缘性好的优良性能,在航空航天、军事医疗、电子信息等领域具有广泛的应用。旋转超声辅助加工的刀具磨损小、材料去除率高、加工精度高,在工业陶瓷精密加工领域取得了较好的运用。本文以常用的石英陶瓷和氮化硅陶瓷为加工对象,进行了表面磨削及钻孔试验研究,通过宏观形貌观察、测量表面粗糙度值、工件及刀具微观形貌分析,确定了PCD砂轮结合超声辅助磨削加工,可以得到较好的表面加工质量。开展了石英陶瓷凹槽面、平面及过渡面的磨削加工试验,取得了较好的表面形貌;利用不同类型的砂轮加工氮化硅陶瓷孔,从而确定高强度的金刚石磨头是加工硬性材料的最优砂轮。     

Prospects for improving machining productivity of large ceramic objects for radio engineering purposes

Contemporary machining methods for ceramic materials are analyzed. Laser, hydroabrasive and high-speed machining are considered. The possibility of using these methods for machining large complexly-shaped ceramic objects having a double surface curvature is evaluated.     

Microstructure design and preparation of Al2O3/TiC/TiN micro-nano-composite ceramic tool materials based on properties prediction with finite element method

The objective of this paper was to improve the accuracy of semi-empirical method used to design ceramic cutting tool materials. The mechanical properties were predicted by employing finite element model of material microstructure, so as to design microstructure and prepare new ceramic materials. Based on the Voronoi and randomness method, the microstructure model representing the complexity and randomness of micro-nano-composite ceramic material microstructure was established. Combining the representative volume element (RVE) of ceramic material microstructure with mechanical tests, the simulations of mechanical tests were conducted to acquire the flexure strength, fracture toughness and hardness of materials. The microstructure models with various parameters were designed and the material properties were predicted to determine the optimal microstructure parameters. Then, The ceramic cutting tool materials possessing the optimal microstructure parameters were developed for machining ultra-high strength steels. The results showed that the mechanical properties of ceramic materials first improved and then declined as the nano-scale TiC volume fraction increased. To obtain the best comprehensive mechanical properties, the contents of micro-scale TiN, TiC and nano-scale TiC were set as 20%, 10% and 10%, respectively. The prepared ceramic materials possessed the flexure strength of 881.4 MPa, the fracture toughness of 7.8 MPa m^1/2, and the Vickers hardness of 20.8 GPa. This research is beneficial to the development of cutting tool design theory and the improvement of the tool life.     

Study on the effect of ultrasonic vibration-assisted polishing on the surface properties of alumina ceramic

Due to the excellent biocompatibility and chemical durability, alumina ceramics are widely used in biomedical fields such as dentistry. Meanwhile, the high hardness and brittleness of the alumina ceramic causes difficulties in ensuring the processing quality of conventional machining methods. Ultrasonic vibration-assisted polishing (UVAP) can effectively improve the surface quality of hard and brittle materials as a novel machining method. The surface properties of the alumina ceramic for different ultrasonic amplitudes are obtained in this study. The evaluation of the surface properties includes microscopic topography, frictional property, surface hardness, microscopic strain, and surface roughness. In addition, a surface roughness model of the alumina ceramic is built based on the UVAP machining mechanism. The model considers the effect of different types of abrasive particles (free and fixed abrasive particles) on the material removal mechanism. The experimental results show that the errors of the predicted model are less than 20%. This work will provide some ideas for the subsequent UVAP processing.