Ceramic heater manufacturers introduce the classification of raw materials
Classification by purpose
1. Daily-use ceramics: such as tableware, tea sets, jars, altars, basins, pots, plates, plates, bowls, etc.
2. Art (craft) ceramics: such as vases, sculptures, garden ceramics, utensils, furnishings, etc.
3. Industrial ceramics: refers to ceramic products used in various industries. It is divided into the following 6 aspects:
①Building a sanitary ceramics: such as bricks, tiles, drain pipes, facing bricks, exterior wall bricks, sanitary ware, etc.;
②Chemical (chemical) ceramics: used in acid-resistant containers, pipelines, towers, pumps, valves, and acid-resistant bricks and ash for lining reaction pots in various chemical industries;
③Electric porcelain: used for insulators on high and low voltage transmission lines in the power industry. Motor bushings, post insulators, low-voltage electrical and lighting insulators, telecommunications insulators, radio insulators, etc.;
④Special ceramics: special ceramic products used in various modern industries and cutting-edge science and technology, including high alumina ceramics, magnesia ceramics, magnesia ceramics, zircon ceramics, lithium ceramics, and magnetic ceramics , Cermet, etc.
Folding according to the degree of material density
Ceramic heater manufacturers
Stoneware (brickware or terra-cotta), fine pottery (potttery), stoneware (stone Ware), semivitreous china (semivitreous china), and even porcelain (porelain), the raw materials are from coarse to fine, the body is from coarse loose porous , Gradually reach the density, sintering, and the firing temperature gradually increases from low to high.
Stoneware is the most primitive and lowest-grade ceramic ware, generally made of a kind of fusible clay. In some cases, clinker or sand can also be added to the clay to reduce shrinkage. The firing temperature of these products varies greatly, depending on the nature and amount of impurities contained in the chemical composition of the clay. To make bricks and tiles, if the porosity is too high, the frost resistance of the green body is not good, and the mortar is not easy to hang on the fork if it is too low, so the water absorption rate should generally be maintained between 5-15%. The color of the green body after firing is determined by the content of colored oxides in the clay and the firing atmosphere. It is mostly yellow or red when fired in an oxidizing flame, and blue or black when fired in a reducing flame.
The blue bricks in my country’s building materials are made of yellow or red clay containing Fe₂O3 as raw materials. They are calcined with a reducing flame when the fire is stopped to reduce Fe203 to FeO into a blue color. Pottery can be divided into ordinary pottery and fine pottery. . Ordinary pottery refers to earthenware pots. Tanks, tanks, urns. And refractory bricks and other products with porous colored bodies. The water absorption rate of fine pottery body is still 4-12%, so it has permeability, no translucency, generally white, but also colored. The glaze is mostly fusible glaze containing lead and boron. Compared with stoneware, because the amount of flux is less and the firing temperature does not exceed 1300°C, the green body is not fully sintered; compared with porcelain, the requirements for raw materials are lower, the plasticity of the blank is greater, and the firing temperature is higher. Low. It is not easy to deform, so it can simplify the forming, potting and other processes of the product. But the mechanical strength and impact strength of fine pottery are better than porcelain. The stoneware should be small, and its glaze is softer than the glaze of the above products. When its glaze layer is damaged, the porous body is easily stained, which affects hygiene.
Fine pottery can be divided into four types according to the composition of the body: clay, lime, feldspar, and clinker. Fine clay pottery is close to ordinary pottery. Lime-based fine pottery uses limestone as flux, and its manufacturing process is similar to that of feldspar-based fine pottery, but the quality is not as good as feldspar-based fine pottery. Because it has been rarely produced in recent years, it has been replaced by feldspar-based fine pottery. Feldspar fine pottery, also known as hard fine pottery, uses feldspar as a flux. It is the most perfect and widely used kind of pottery. In recent times, many countries used large-scale production of daily-use tableware (cups, plates, etc.) and sanitary pottery to replace expensive porcelain. Hot material fine pottery is to add a certain amount of clinker to the fine pottery blank, the purpose is to reduce shrinkage and avoid waste. This kind of blank is mostly used in large and thick tire products (such as bathtubs, toilet bowls, etc.).
Stoneware is called "stone porcelain" in ancient Chinese books. The body is dense and completely sintered, which is very close to porcelain. However, it has not been vitrified yet, and still has a water absorption rate of less than 2%. The body is opaque and white, and most of it is allowed to show color after firing. Therefore, the purity of the raw materials is not as high as that of porcelain, and the raw materials are easy to obtain. Stoneware has high strength and good thermal stability, is very suitable for modern mechanized washing, and can smoothly pass the rapid temperature change from refrigerator to oven. In the international market, due to the development of tourism and the socialization of food, Stoneware has a larger sales volume than enamel.
The semi-porcelain blank is close to the porcelain blank, but it still has a water absorption rate of 3 to 5% after firing (real porcelain, the water absorption rate is below 0.5%), so its performance is not as good as porcelain, but better than fine ceramics.
Porcelain is a higher stage in the development of ceramics. Its characteristic is that the green body has been completely sintered and fully vitrified, so it is very dense and has no permeability to liquids and gases. The thin part of the tire is semi-transparent, and the cross section is shell-shaped. When you lick it with your tongue, it feels smooth and not sticky. live. Hard porcelain has the best performance among ceramics.