Terra cotta products

The nature of the raw materials used for the manufacture and the chemical and mineralogical compositions of the shards can also be used as additional criteria for classificatiom 

We are referring here to potteries or construction products such as roof tiles, bricks, flues, drainage pipes or some floor tiles. Terra cotta products were obtained a long time ago by modeUng, drying and firing cormnon clays. Nowadays, the compositions are more complex they combine clays and additives, such as coloring, 

Terra cotta products are porous and mechanically resistant. They are marketed raw, enameled or covered with a glaze realized at low temperature, between 600 and 900°C, called varnish. They are appreciated for their esthetic quality, their stability through time and their hygrothermic and acoustic properties. They represent a highly automated industrial sector which is the scene of continual technological developments. 

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Red clays used for the manufacture of terra cotta products are actually natural mixtures with a complex composition. They generally contain kaolinite, illite and/or other clays rich in alkaline, sand, mica (formula Si3Al3Oi0(OH)2), goethite (FeO(OH)) and/or hematite (Fe203), organic matter and, very often, calcium compounds. The latter, just like the micas and the other alkaline-rich compounds, help lower the firing temperature of the shard. 

Potteries glazed with fusible argillaceous paste are very close to terra cotta products. Just like them, they are obtained from common argillaceous soils, relatively fusible, and naturally containing a certain quantity of sand. Although their sintering, carried out between 900 and 1,060°C, takes place in the presence of a significant quantity of liquid, their shard is still porous. 

Ceramic industries. The chemical and physical properties of silicates are utilized to advantage in a group of industries which collectively may be termed the ceramic industries. These are concerned with the manufacture of products such as cement, glass, porcelain, bricks, tile, terra cotta, and enamels. All these industries utilize a wide variety of complex naturally occurring silicates. 

Sulfur Mortars Hot melt-and-pour sulfur mortars are ancient, doubtless one of the oldest of all chemical resistant materials still used today. They are very resistant to non-oxidizing acids and weak alkalies below 200°F over a pH range of 0-12. Three types of sulfur mortars are typically employed (1) One containing an all-silica filler with minimum plasticizer, used to bond acid brick (2) A mortar with an all-carbon filler and minimum plasticizer, used primarily to lay carbon brick for nitric-hydrofluoric acid pickling tanks (to clean stainless steels) and the underlying floors and (3) A much more flexible all-silica filled product with double the amount of plasticizer of the other two mortars, used to join vitrified clay (terra cotta) pipe conveying waste acids and other effluent chemicals, and to assemble "pole line hardware" for the power industry. 

Earthenware is made from red earthenware clay and is fired at fairly low temperatures, typically between 950 and 1050°C. It is porous when not glazed, relatively coarse, and red or buffcolored, even black after firing. The term pottery is often used to signify earthenware. The major earthenware products are bricks, tiles, and terra cotta vessels. Earthenware dating back to between 7000 and 8000 bce has been found, for example, in Catal Hiiyiik in Anatolia (today s Turkey). 

Products Bricks, terra cotta, roofing tiles Flue lining, insulating bricks Acid-resistant bricks, cement-clinker Split bricks, quarry tiles Pottery verified ware, table ware Sanitary ware, tiles, insulators Table ware Chemical ware refractory ware... 

In modem science, ceramic is used in various aspects. Besides this ceramics developed on the basis of clay have some special uses such as stmctural building materials, refractory materials, non-stmctural products, stmctural products, earthen ware, stone ware, porcelain, and technical ceramics. The products of ceramic materials are known to us as bricks, terra cotta, flue lining, cement-clinker, chemical ware, refractory ware, table ware, tiles, sanitary ware, insulators, split bricks, quarry tiles, acid-resistant bricks etc. 

Among the many other ceramic applications in which wollastonite can be used are glazed porous ceramics of nearly every kind, dinnerware, ovenware, artware, structural clay products, terra cotta, sanitaryware, chemical stoneware, ceramic-bonded abrasives, refractories, high alumina bodies, spark plugs, electrical porcelains, frits and investment castings. 

These products of terra cotta, earthenware, sandstone, porcelain or vitreous china are generally widely marketed materials. They represent a predominant share in the total sales trrmover of the ceramic industry. In 1994, the fields of roof tiles and bricks, wall and floor tiles, crockery and omamentatiorr, and sanitary products... 

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