Nonmetallic materials silicates

Ceramics are typically made from clays (which contain silicates) that are hardened by firing at high temperatures. Ceramics are a class of nonmetallic materials that are strong, brittle, and resistant to heat and attack by chemicals. 

But not all ceramic materials are clay (glass is made of sand], and they don t all behave the same way. They are, it turns out, far more interesting and versatile than one might imagine. For years, ceramics were generally defined as inorganic, nonmetallic materials, are known primarily as silicate bearing, that is, composed of the natural minerals that make up most of the rocks in the earth s crust. 

Ceramic a nonmetallic material made from clay and hardened by firing at high temperature it contains minute silicate crystals suspended in a glassy cement. (10.5)... 

In the following sections, we look at several nonmetallic materials with applications in modem technology. We begin with a discussion of the different allotropes or forms of carbon—diamond, graphite, and the fullerenes—where research has produced some exciting discoveries (Section 13.4). The fullerenes are recently discovraed molecular forms of the element carbon, in which the carbon atoms form hollow balls and tubes that may make them important as catalysts or possibly as drug-delivay mataials. Diamond shows promise as a material that might supersede silicon in its role as a matmal for sohd-state electronics. Silicon and diamond can act as semiconductors, which we discuss in Section 13.5. We end the chapter with sections on silicon, silica, and silicates (Section 13.6), ceramics (Section 13.7), and finally composites (Section 13.8). 

Ceramics are studied and used for such places that are subject to high temperatures, but many others have a variety of nses. Ceramics is dehned as an inorganic, nonmetallic material processed or consolidated at high temperatnres. Ceramics includes silicates, oxides, carbides, nitrides, snlhdes, and borides of metal or metalloid. The traditional ceramics are mostly silicates as discnssed earlier and nsed as a pot or similar purposes. But today ceramics are pursued as material for high-temperature, electric properties such as ferroelectricity, piezoelectricity, magnetic properties, high mechanical properties, and optical properties. In a word, they are pnrsned as HIGH-TECH material. 

Silicon is a nonmetallic chemical element that is used quite extensively in the manufacturing of transistors and various electronic and computer chips. Pure silicon is not found in nature it is found in the form of silicon dioxide in sands and rocks or found combined with other elements such as aluminum or calcium or sodium or magnesium in the form that is commonly referred to as silicates. Silicon, because of its atomic structure, is an excellent semiconductor, a material whose electrical conductivity properties can be chai d to act either as a conductor of electricity or as an insulator (preventor of electricity flow). Silicon is also used as an alloying element with other elements such as iron and copper to give steel and brass cert desired characteristics. 

The word ceramics is derived from the Greek keramos, meaning solid materials obtained from the firing of clays. According to a broader modern definition, ceramics are either crystalline or amorphous solid materials involving only ionic, covalent, or iono-covalent chemical bonds between metallic and nonmetallic elements. Well-known examples are silica and silicates, alumina, magnesia, calcia, titania, and zirconia. Despite the fact that, historically, oxides and silicates have been of prominent importance among ceramic materials, modern ceramics also include borides, carbides, silicides, nitrides, phosphides, and sulfides. 

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