Ceramics - Incredible Refractory Materials :: Art

Ceramics - Incredible Refractory MaterialsIntroduction First we will start with the description of refractories and ceramics. Refractories and ceramics are non-metallic materials capable of maintaining physical and chemical stability at high gear temperatures. Refractories in modern practice are usually ceramic in nature, and are used in a wide variety of primary, secondhand and tertiary industries. Wherever an industrial demonstrate involves heat in extra of 700 to 800 degrees Fahrenheit (roughly), one will find refractory material in place, either as a lining or forming the process vas itself. Some common process vessels using refractories are boiler electrocution chambers, furnaces like the one in the foundry, incinerators, many emission control scrubbers, roundab show up kilns and so on. The list is by know means exhaustive. For example, Launch Pads 39A and 39B at the Kennedy Space Center are refractory lined. The shuttles themselves are lined with ceramic tiles to protect them from the heat of re-entry into earths atmosphere, these tiles are unique to the shuttle, plainly are non-metallic and heat resistant. The Making of Refractory Materials The first step in processing ceramics is oppress of the raw materials. Crushing is usually done in a ball mill, either wet or dry. Wet crushing is much effective because it keeps the wearicles together and prevents the suspension of fine particles in air. The purpose particles are then mixed with additives, the functions of which are one or more of the following 1. Binder for the ceramic particles 2. Lubrication for mold release and to reduce privileged friction between particles 3. Wetting agent to improve mixing 4. plasticizer to make the mix more plastic and formable. 5. Various agents to control foam and sintering. 6. De-flocculent to make ceramic-water suspension. De-flocculention changes the electrical charges on the clay particles so that they repel alternatively of attract each other. Next, its t ime to begin the molding process. The plastic process for refractories are casting plastic forming and pressing. The most common casting process is slip casting. The slip is poured into a porous mold make usually of plaster of paris. Then inverted and the remaining suspension is poured out for making hollow object much like slush casting. The part is then trimmed the mold opened and the part removed. The second process of shaping ceramics is plastic forming. We have various methods of plastic forming such as extrusion, injection molding and jiggering. Plastic forming tends to orient the layered structure of clays on the direction of material flow.