Fracture Toughness Enhancement for Alumina Systems: A Review

Investigations have been carried out to determine ways of tailoring ceramic materials in order that one or more toughening mechanisms are activated in service. Microstructural manipulations, as well as composite formulations involving metallic, intermetallics, and ceramic phases have been used with ceramic matrices. Macrostructurally, laminated structures and functional gradient materials (FGMs) have also been formulated to enhance mechanical properties. Although significant improvements in material properties have been reported, ceramics are still below their projected positions on the materials map. This article presents a review of research activities pursuant to improving fracture toughness of alumina matrix systems and the enhancements achieved.     

Research trend in the development of macroporous ceramic components by pore forming additives from natural organic matters: A short review

Macroporous ceramics with tailored porosity offer a great deal of advantage in wide-ranging industrial applications including fluid filtration, thermal insulation and lately, waste water treatment. To a large extent, attempts by researchers in enhancing the development of ample homogenous porous ceramics through the exploitation of state of the art processing technologies have thus far been successful. However, these technologies are capital intensive hence making room for more exploration in finding affordable alternatives. With the growing recognition of low cost sacrificial fugitives processing route for developing porous ceramic materials, pore forming agents from natural organic matters have been one of the most sought after materials for imbuing pores within ceramic matrices. This review intends to document the progress made thus far in the development of porous ceramic systems with natural organic matter inclusion. The article covers critical evaluation and comprehensive comparison of the fabrication routes and the physical properties of porous ceramics processed with varying natural organic matters.     

Facile processing of oriented macro-porous ceramics with high strength and low thermal conductivity

Unidirectionally oriented architectures demonstrate a notable efficiency in enhancing the properties of macro-porous materials, yet are difficult to construct in a time- and cost-effective fashion. Here a facile approach was exploited for fabricating oriented macro-porous ceramic materials by employing natural graphite flakes as a fugitive material and preferentially aligning the flakes within ceramic matrices using accumulative rolling technique. Flaky to near-ellipsoid shaped pores with a homogeneous distribution were created in macro-porous zirconia ceramics with their porosity and microstructural characteristics adjustable by controlling the additive amounts of graphite flakes. The resulting materials exhibited a good combination of properties with high compressive strength up to over 1.5 GPa, which exceeds those of most other porous zirconia ceramics with similar porosities, along with low thermal conductivity of 0.92–1.85 Wm^?1·K^?1. This study offers a simple means for developing new oriented macro-porous materials with enhanced properties, and may promote their application by allowing for easy mass production.     

电子陶瓷和器件的低温共烧技术

较系统地介绍了电子器件用低温共烧陶瓷(low temperature cofired ceramics,LTCCs)材料,探讨了其工艺中的若干问题。电子器件用低温共烧陶瓷材料包括:玻璃/陶瓷复合材料、结晶化玻璃、晶化玻璃/陶瓷复合材料以及液相烧结陶瓷,其中典型的和最为常用的LTCCs为玻璃/陶瓷(特别是氧化铝)复合材料。正在研究的一些陶瓷介质材料中,Bi基介质材料引起了人们的关注。玻璃/陶瓷复合材料的制备工艺中,应当着重关注和加深了解玻璃的流动性和结晶性、玻璃的起泡、玻璃和陶瓷颗粒间的反应、共烧材料的匹配等问题,从优选材料配方和优化工艺着手,从而获得优质可靠的材质和器件。     

陶瓷材料凸显优势信息产业引领未来

能源、信息、材料是现代科技的三大支柱,新技术的出现有时很大程度上是材料性能的突破而带来的,这是因为新技术的发展往往依赖于新材料来体现它的新性能。随着我国经济一体化的发展,电子陶瓷行业的经济、技术竞争能力将有更大的提高,电子陶瓷市场的消费环境与拥有现状、消费需求潜力、以及电子陶瓷未来的发展趋势成为企业关注的焦点。针对电子...     

Selected Emerging Opportunities for Ceramics in Energy,Environment, and Transportation

Novel ceramic materials and advanced techniques for processing them and controlling their microstructure are breaking new ground in the areas of energy, environment, and transportation. For example, terahertz (THz) properties of ceramic materials and advanced structures reveal their potential for sensing in energy and environmental applications as well as local communication networks in transportation. Emerging opportunities for the development of improved porous ceramics for engine emissions control are discussed in particular, in consideration of the key role that this technology has with respect to global environmental and transportation concerns. Moreover, it is anticipated that advanced ceramics and composites of certain classes will enable innovation in nuclear energy by providing breakthrough accident‐tolerant features. In this article, we highlight these three areas of ceramics that are critical to the future and also show promise for growth.     

Advanced ceramics and coatings for erosion-related applications in mineral and oil and gas production: A technical review

The applications of advanced ceramics, composites and coatings in mineral, mining, fuel production, and processing are reviewed. The materials include oxide and non-oxide ceramics (specifically SiC-based), ceramic–ceramic, and ceramic–metal composites, coatings on metallic components where functional application properties can be achieved. Some principles of materials selection, specifically for erosion wear and corrosion applications, and manufacturing are considered. The examples of the successful development and processing of ceramics, coatings, and composites with manageable structures and phase compositions, in the erosion-related applications, particularly conducted by the author, are discussed and reviewed. Specifically, industrially employed types of ceramics and processing routes were focused on the considered applications. Particular demands for advanced materials with high reliability and complex shapes or for protective coatings on complex shape steel components and long tubing with inner surface protection require novel and optimized processing. The factors affecting erosion and erosion–corrosion resistance and the paths for the erosion resistance enhancement of ceramic and coating materials are considered. Ceramic components design, technology, and installation features are reviewed.     

工程陶瓷材料的声透射特性研究

针对工程陶瓷材料对声波的传播过程中声透射系数问题,从波动方程入手,利用传递矩阵法及声波气-固边界条件建立了声波在工程陶瓷材料的声透射系数特性数学模型,研究了垂直入射条件下不同频率声波在工程陶瓷材料中的声透射系数规律.仿真结果表明,当工程陶瓷材料的厚度为半波长整数倍时,此时声透射系数最大;当声波的频厚积是陶瓷厚度与其声速乘积一半的整数倍时,此时声透射系数最大.为工程陶瓷材料的隔声性能分析及声学检测提供了一定的理论基础.     

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。     

Ballistic performance of armour ceramics: Influence of design and structure. Part 2

The use of advanced ceramics for armour systems allows the defeating of the projectile and ballistic impact energy dissipation providing adequate ballistic protection. The development of lightweight and inexpensive ceramics and armour designs is under ongoing attention by both ceramic armour manufacturers and armour users. This paper summarizes the results of extensive studies of ballistic performance of different armour ceramics, mostly obtained during development, as well as of the materials manufactured by other recognized armour ceramic suppliers, and the designed ceramic-based armour systems. The studied armour ceramics include homogeneous oxide and carbide ceramics and heterogeneous ceramic materials. Ballistic performance of the studied ceramics as function of their structure and properties, armour system design and type of projectile has been discussed. Depending on the requirements for ballistic protection, armour systems may be designed to various configurations and weights based on the most suitable ceramic materials and backing. The examples of successful designs of lightweight armour systems with adequate ballistic performance, including satisfactory multi-hit performance, have been demonstrated.     

Impact of the addition of dolomite to cream-firing clays on the technological and color properties of sintered ceramics

Sintered ceramics, represented by ceramic tiles or clinker bricks, are widely used in the building materials industry due to their technological properties and visual qualities. The topic of color changing of ceramic materials from cream-firing clays with the use of mineral additives has not been addressed to date. The aim of the paper was to investigate the effect of granulation of dolomite additives to ceramic masses based on cream-firing Borkowice clay on the color and properties of fired ceramic materials. The paper proposes that grain size of mineral additive affects the color of sintered ceramics. In order to confirm this hypothesis, a number of experiments were performed, consisting of determination of the color and technological properties of ceramic materials. The conducted tests showed that the color and technological properties of sintered ceramics are influenced by the grain size of the additives used.     

碳纳米管增强陶瓷复合材料研究进展

本文简要评述了近年来CNTs陶瓷复合材料的主要制备方法和特点以及烧结工艺,指出了目前碳纳米管增强陶瓷复合材料存在的问题,并对未来制备CNTs陶瓷复合材料进行了展望。     

复相陶瓷材料的设计原则

根据陶瓷材料在使用上的性能要求，设计和确定材料的组成、显微结构和工艺，是陶瓷材料研究的进步。陶瓷材料向多相方向发展，为陶瓷材料的晚思考余地。本文阐述了复相陶瓷瓣设计原则，显微结构的设计，不同相之间的化学共存，不同相之间的物理匹配。     

值得关注的特种精细陶瓷材料

现代高科技为陶瓷的发展注入了新的活力,特种精细陶瓷材料和高分子合成材料相结合,将成为名副其实的耐高温的高强度材料。针对特种精细陶瓷有广阔的发展前景,阐述了特种精细陶瓷应用于国民经济的各个领域,介绍了特种精细陶瓷的种类及与传统陶瓷的主要区别,研究了典型的特种精细陶瓷——微孔陶瓷过滤材料,提出了特种精细陶瓷在未来汽车零部件上的研发趋势。     

特种陶瓷的发展与展望

本文回顾了陶瓷材料的发展历史,着重评述了特种陶瓷如工程结构陶瓷、陶瓷基复合材料、生物陶瓷、功能陶瓷等的发展现状,并展望了特种陶瓷的未来发展。     

陶瓷减水剂、助磨剂、增强剂的发展现状、趋势及展望

阐述了陶瓷行业所用添加剂的分类，以及目前国际上主要生产陶瓷添加剂的厂家及主要产品，详细介绍了陶瓷坯体减水剂、助磨剂、增强剂的种类、应用、性能特点和它们与陶瓷材料的作用机理，并对陶瓷添加剂的发展前景进行了展望。     

陶瓷及其复合材料合成的机械力化学效应

介绍了陶瓷及其复合材料(如：氧化物陶瓷、生物陶瓷、电子陶瓷、微波绝缘复合陶瓷、电池材料和sialon陶瓷复合材料)合成的机械力化学效应研究的进展。软机械力化学合成方法的生产成本低,将该方法用于工业化生产各种陶瓷材料具有相当大的应用前景。通过选择合适的原料和研磨条件,机械力化学合成的方法可用于制备很多高性能无机材料。用机械力化学合成的方法可加速并简化合成反应,减少能量和原材料的消耗,即经济又环保。同时,机械力化学合成的方法可以通过非常规的途径使纳米结构陶瓷材料晶化反应快速进行。针对此研究领域将来的发展方向提出了建议。     

Binder jetting of ceramics: Powders,binders, printing parameters,equipment, and post-treatment

Binder jetting is expected to become the universal process for preparing ceramic parts because it can overcome multiple problems, such as the difficulty to prepare complex-shaped ceramic parts and the shrinkage of the sintering process, which appear in conventional ceramic preparation process. This paper introduces principles, steps, and applications of binder jetting printing ceramics. Furthermore, five key factors of binder jetting printing ceramics (powders, binders, printing parameters, equipment, and post-treatment process) have been investigated. Accordingly, effects of powders (including shape, particle size and distribution, and additives), binders (including binding method, droplet-formation mechanism, and droplet-infiltration kinetics), printing parameters (including layer thickness, saturation, solid binder, and printing orientation), equipment, and post-treatment (including de-powdering process, and densification process) on density, roughness, strength, accuracy, and resolution of ceramic parts have been discussed and summarized. This paper provides detailed analysis of techniques and mechanisms of binder jetting of ceramics, giving guidance on how to handle raw materials and select various processing parameters for achieving desired performance.     

氮化硅陶瓷在四大领域的研究及应用进展

氮化硅陶瓷不仅具有较高的力学性能还具有良好的透波性能、导热性能以及生物相容性能,是公认的综合性能最优的陶瓷材料。作为轴承球的致密氮化硅陶瓷广泛应用在机械领域;作为透波材料的多孔氮化硅陶瓷广泛应用在航空航天领域;随着对氮化硅陶瓷材料的深入研究,其在导热性和生物相容性方面的优异特性逐渐被科研工作者认识并得到开发和应用。本文详细阐述了氮化硅粉体的制备方法,并综述了氮化硅陶瓷作为结构陶瓷在机械领域和航空航天领域的研究进展,此外还介绍了其作为功能陶瓷在半导体领域、生物制药领域的研究和应用现状,最后对其未来发展进行了展望。     

高温自润滑陶瓷复合材料研究进展

工作于高温环境中的陶瓷摩擦副,其润滑问题必须得到解决。由于传统润滑方法难以实施,研制具有自润滑性能的陶瓷或其复合材料无疑是一条很好的途径。本文综述了固体润滑剂、陶瓷以及陶瓷复合材料的高温干摩擦的研究现状。试图分析找出实现这一目标的途径。