Ceramics, traditional

A ceramic is an inorganic non-metallic solid prepared from powdered materials and can loosely be divided into cement, mortar and concrete, glass and glass ceramics, traditional ceramics, and what may be termed advanced (i.e. high performance, technical, engineering, or fine) ceramics. 

Some elements such as carbon and silicon m be considered as ceramics. Traditional ceramic raw materials include cl minerals such as kaolinite, whereas more recent materials include aluminium oxide, known as alumina and also include silicon carbide and tungsten carbide. Ceramic materials are brittle, hard, and strong in compression, weak in shearing and tension. They... 

Oxides are the most common constituents of all ceramics, traditional and technical. An extensive account is given in [2.8]. They are used for their physical as well as refractory properties. Table 3.2-9 presents a systematic... 

Hard materials like metals and ceramics traditionally have been used for actuators. However, soft materials with smooth movement are also useful depending on the purpose. In particular, light and smoothly fimctioning actuators are desirable as medical devices and artificial organs that have direct contact with the human body. In this section, the study of a conducting polymer, polyaniline, will be used as an example. The dependence of deformation ratio on the electrolyte solution and load will be described. Furthermore, the measurement results and the fimc-tional mechanism of excess response characteristics will also be discussed. 

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]. 

HAR 97] HARRIS V., Jomon Pottery in Ancient Japan , Pottery in the making, world ceramic traditions. Freestone I, Gaimster D. (ed.), British Museum Press, 1997. 

Cordierite [12182-53-5] Mg Al Si O g, is a ceramic made from talc (25%), kaolin (65%), and Al O (10%). It has the lowest thermal expansion coefficient of any commercial ceramic and thus tremendous thermal shock resistance. It has traditionally been used for kiln furniture and mote recently for automotive exhaust catalyst substrates. In the latter, the cordierite taw materials ate mixed as a wet paste, extmded into the honeycomb shape, then dried and fired. The finished part is coated with transition-metal catalysts in a separate process. 

Fig. 2. Examples of traditional ceramics manufactured usiag traditional ceramic raw materials clay, flint, Si02 and feldspar.

Conventional Sintering Equipment. Like drying furnaces, sintering furnaces (29,76,85) can be periodic or continuous in nature. Periodic kilns offer greater flexibiHty continuous tunnel kilns are more economical. Advanced ceramics are typically siatered in high purity, controUed atmosphere furnaces by electric resistance heating. Ceramic furnaces used to fire traditional ceramic ware are generally heated with inexpensive natural gas, oil, wood, or coal. 

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