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Glass and Ceramic raw materials and quality
Glass is a solid amorphous substance. Glass is usually brittle and transparent.
Glass - composition Amorphous brittle material. When glass is heated, it does not liquefy or solidify in a certain way, like crystalline substances, but gradually changes from a solid state to a soft state, and finally to a liquid state. When the liquefied glass solution cools, it first plasticizes and then solidifies at certain intervals. Glass is isotropic, meaning that its physical properties (refractive index, thermal conductivity, etc.) are the same when measured in different directions. Depending on the type of inorganic compounds they contain, glass is divided into the following classes: elemental glass, oxide glass, halogen glass, chalcogenide glass, and mixed glass.
Elemental Glass - consists of atoms of only one element. Sulfur, selenium, arsenic, phosphorus, and some metals can be obtained in the form of glass when cooled rapidly.
According to their use, construction glass (window glass, glass blocks, etc.), architectural construction glass, car glass, thermally stable glass, chemical lab. There are Glass, Medical Glass, Optical Glass, Electrovacuum Glass, Lighting Glass, Container Glass, Glass, as well as Glass fiber and Glass plastics. Glass that protects from ionizing radiation, Glass of permeable radiation indicators, Glass with variable light transmitting, Glass used as laser material, Soluble Glass, etc. produced.
The most characteristic feature is its transparency (the transparency of the window pane is 83-90%, and the optical city is up to 99.95%). Glass is a brittle body, very sensitive to mechanical shocks. Density 2200-8000 kg / m³. In nature, there are natural glasses such as perlite, obsidian (see Volcanic glass). The appearance of artificial glass is usually associated with pottery. In pottery, soda and sand may have been added to the clay during firing, resulting in a glassy glaze on the surface of the pottery. Glass is baked in the industry, mainly in bath ovens and special jars. Glass firing process involves liquefaction, clarification (purification of air and other gases), homogenization and cooling of the glass mass. The glass is baked at 1400-1450 °, clarified and homogenized at 14601500 °, cooled at 1200-1300 °. The city is shaped and made by pressing, puffing, stretching and rolling.
Ceramics (Greek keramos - soil) - mirror materials and materials obtained by baking clay (clay, kaolin) or inorganic substances in high temperatures. In all areas: household (dishes), construction (bricks, tiles, pipes, tiles, wall decorations), engineering (radio engineering, electrical engineering, aerospace), t. K. in water and air transport, in sculpture and applied arts. According to their structure, they are divided into coarse (consisting of unevenly distributed large particles, porosity 5-30%) and fine (evenly distributed fine particles, porosity up to 5%). D agal K. includes most building materials, mas, bricks and tiles, fine K. includes ceramics, porcelain, tiles, piezo and segnetoceramics, ferrites, cermets, some refractory materials, semi-porcelain and majolica. According to its chemical composition, K. oxide, carbide, nitride, silicide, optical, etc. To make ceramics, soil, kaolin, sand, feldspar, metallurgy and some industrial wastes are first pulverized in a ball mill and mixed with water; the resulting mixture is poured into the mixing basins; Depending on the molding method, it is dehydrated to a certain extent in filter presses or special spraying devices. Then in the form of a powder with a moisture content of 6-12% Products are made from alloys by means of presses, by spreading, pressing or forming ceramic wheels from 15-25% alloys. Mixtures containing 25-45% water are molded into gypsum, porous plastic and metal molds. The molds are dried and baked in special ovens from 900 ° (for construction K.si) to 2000 ° (for flammable K.si). Some types of K. are subjected to additional machining and finishing after cooking. Ceramics, porcelain, earthenware and other types of elegant K. are coated with a glaze that forms a waterproof and gas-tight glass layer and are baked at 1000-1400 °. In the manufacture of heat-insulating porous materials, highly flammable additives (coal, sawdust, organic matter) are added to the clay, and when the additives burn, the remaining pores form pores. They were rediscovered in China in the 3rd-4th centuries AD, in the Middle East in the 9th-10th centuries, in Central Asia in the Middle Ages, in France in the 16th century, in Germany and England in the 18th century, and in Russia in the 19th and 20th centuries. advanced Chinese porcelain and faience played an important role in the world history of K.'s development. He had a significant impact on the development of K. in many countries in Europe and Asia. In Central Asia, Iran, Azerbaijan, Turkey, and the Arab world, K. played an important role in decorating buildings, using bubble terracotta, and making dishes. Polychrome mosaic tiles for buildings built in the 10th and 15th centuries in Khiva, Samarkand, Bukhara, Kokand and Tashkent are the greatest achievements of architecture (see K. traversed the path of development.
TEST
1.What chemical effects is glass resistant to?
A) electrical heat sound insulation B) no durability feature C) A and B Jacob is correct
2. How much is a household bottle divided into?
A) 3 ta B) 5 ta C) 6 ta
3. What is the inside diameter of the mouth of a narrow glass container?
A) less than 60 mm B) less than 80 mm C) less than 30 mm
4. What is the inside diameter of the mouth of a wide-necked glass container?
A) 30 mm large B) 40 mm large C) 80 mm large
5. From which word is the word “ceramic” derived?
A) Arabic B) Greek C) Latin
6. How many ceramic goods are divided?
A) 4 B) 6 C) 8
7. Classification of ceramic goods?
A) building materials B) coarse and fine ceramics C) TJY
8. What is the meaning of the word “ceramics”?
A) porcelain pottery B) sand pottery C) pottery
9. What is the function of ceramics and ceramics?
A) 4 B) 3 C) 7
10. How many oxides are mainly in a glass container?
A) 3 ta B) 2 ta C) 6 t
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