Traditional and Advanced Ceramics

) (1970-1971) High Temperature Oxides, 4 volumes. Academic, New York. 

Aronsson, B. Lundstrom, T. Rundquist, S. (1965) Borides, SUicides, and Phosphides. Methuen, London. Billups, W.E. Ciufolini, M.A. (1993) BuckminsterfuUerenes. VCH, Weinheim. 

Morando, P.J. Regazzoni, A.E. (1994) Chemical Dissolution of Metal Oxides. CRC Press, Boca Raton, FL. 

Bradshaw, W.G. Matthews, C.O. (1958) Properties of Refractory Materials Collected Data and References. 

Brixner, L.H. (1967) High Temperature Materials and Technology. Wiley, New York. 

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Figure 1.1 compares traditional and advanced ceramics in terms of the type of raw materials used, the forming... 

Before describing each class, a description of the most common raw materials used in the manufacture of traditional and advanced ceramics, refractories, and glasses is presented below. 

Despite the wide availability of several comprehensive series in materials sciences and metallurgy, it is difficult to find grouped properties either on metals and alloys, traditional and advanced ceramics, refractories, polymers and elastomers, composites, minerals and rocks, soils, woods, cement, and building materials in a single-volume source book. 

Table 11.1 Differences Between Traditional and Advanced Ceramics... 

Ceramic Abstracts. 1975-. Staffs, U.K. CERAM Research Ltd Bethesda, MD Cambridge Scientific Abstracts. This is a comprehensive database for the ceramics industry, providing international coverage on the manufacture, processing, applications, properties, and testing of traditional and advanced ceramics. Includes World Ceramic Abstracts and is included in CSA Materials Database with METADEX (from Web site). 

FIGURE 9.5 A large continuous furnace used in industry to produce traditional ceramic products and advanced ceramics such as multilayer chip capacitors. 

Ceramic oxides represent the most extensive group of ceramic materials produced today. Traditionally, but rather artificially, the oxide ceramics are divided into traditional and advanced groups. The traditional ceramics include mostly silica-based products prepared from natural raw materials (clays), including building parts (bricks, tiles), pottery, sanitaryware, and porcelain, but also ceramics with other main components (e.g., alumina, magnesia), which are applied in the field of electroceramics (insulators), or industrial refractories. 

Silicates represent the dominant eategoiy of the traditional ceramics and glass industries. These materials are economical due to the abundant availability of raw materials. Also, silicates provide adequate mechanical, thermal and optical properties for a wide range of traditional and advanced materials applications. 

This chapter deals with the preparation of ceramic materials such as pigments by sol-gel methods. Ceramics include a wide range of materials - from pottery to electronic materials. Accordingly, it can be classified into traditional ceramics - materials developed since the early civilizations until 1940 - and advanced ceramics - materials technically developed post-1940. Clay, refractories, glasses, cements, and concretes are considered traditional ceramics, whereas ceramics used in electrical, magnetic, electronic, and optical applications as well as in structural applications at elevated temperatures are called advanced ceramics. Traditional ceramics still constitute a major part of the ceramics industry [1]. 

Since the Earth s cmst is primarily made up of silicates, we can understand why all ceramics that come close, by near or by far, to terra cotta are silicate materials. Silicate ceramics form, in tormage, the majority of the world of ceramics. They are often described as traditional ceramics, a term which we do not endorse because it may be understood as opposed to progress and technical improvements - whereas many silicate ceramics are sophisticated materials - but which is justified by history it was only at the end of the 19 century that non-siUcate ceramics came to the scene, with specific uses that explain their other name, technical ceramics. Our choice here is to use silicate ceramics and non-silicate ceramics , rather than opposing tradition and advanced technology. We may note that almost all industrial glasses and cements are also sihcate compounds. 

The traditional or conventional ceramics are generally in monolithic form. These include bricks, pottery, tiles and a variety of art objects. The advanced or high-performance monolithic ceramic materials represent a new and improved class of ceramic materials where, frequently, some sophisticated chemical processing route is used to obtain them. Generally, their characteristics are based on the high quality and purity of the raw materials used. Examples of these high-performance ceramics include oxides, nitrides, carbides of silicon, aluminium, titanium and zirconium, alumina, etc. 

Slip-casting has been a major part of traditional ceramics processing technology for at least 250 years. It was introduced for the casting of alumina ware in the early part of the last century and since then has been extensively exploited for forming advanced ceramics. 

This movement is a key challenge for the entire field of advanced materials, but it is a particularly exciting challenge for silicon-based polymers. From the point of view of materials, silicon-based polymers span the three traditional domains plastics, ceramics, and metals. Potential applications are equally diverse. Silicon-based polymers range from structural materials, to optoelectronic devices, and to speciality materials for biomedical applications. We are in a unique position to capture the benefits of this merger of materials and polymer science. 

The various types of technical ceramics have mostly been developed in laboratories. Their manufacture is usually based on new findings obtained in connection with the advances in various fields of science and technology although experience from the manufacture of traditional types of ceramics is also made use of. The respective materials are usually very sensitive to the maintenance of manufacturing conditions. This is why perfect control of the manufacturing processes, as well as that of the properties of the final products, is vital. With the exception of talc-based materials, the main raw materials are synthetic substances which provide better possibilites for maintaining constant properties and for their control. 

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