The appearance of pottery was about 6,543,800 years ago. China entered the Neolithic Age and began to settle down to meet the needs of daily life, such as holding water and storing things, which prompted the invention of pottery. China pottery is widely distributed, mainly in the Yellow River basin and the Yangtze River basin. Yangshao culture is a representative cultural type in the Neolithic Age, characterized by painted pottery, also known as "painted pottery culture", which originated from Banpo and Miaodigou, and the decorative patterns have high artistic value. Majiayao culture is a cultural type in the late Neolithic period, slightly later than Yangshao culture, about 5000 years ago. Black pottery is another great invention after painted pottery. About 4000 years ago, during the Longshan culture period, eggshell pottery with unique craftsmanship appeared. In recent years, there are many imitations in Shandong and Hebei, which have high collection value. The pottery figurines in Qin and Han Dynasties were the pinnacle of ancient figure sculpture in China, which made the pottery-making technology and art reach a high level. In addition, the tri-colored pottery in the Tang Dynasty and the purple pottery in the Ming and Qing Dynasties are important contents of China pottery cultural relics, which are worthy of further collection and study.
Ceramics, pottery and porcelain. The traditional concept of ceramics refers to all artificial industrial products with inorganic non-metallic minerals such as clay as raw materials. It includes various products made of clay or clay-containing mixture through mixing, molding and calcination. From the roughest earthenware to the finest exquisite ceramics, it belongs to its scope. Its main raw materials are silicate minerals (such as clay, feldspar, timely, etc. ) is taken from nature, so it belongs to the category of "silicate industry" together with glass, cement, enamel, refractory and other industries.
The development history of ceramics is an important part of China's civilization history. As one of the four ancient civilizations, China has made outstanding contributions to the progress and development of human society, among which the invention and development of ceramics are of unique significance. In the history of China, different dynasties have different artistic styles and different technical characteristics. The English word "china" means both China and ceramics, which clearly shows that China is the "hometown of ceramics". Chang aiyin
As early as 1000 years ago, when Europeans mastered porcelain manufacturing technology, China people had already produced exquisite ceramics. China is one of the earliest countries to use pottery in the world, and China porcelain is highly praised by the world for its high practicality and artistry.
The so-called ceramics refers to the products made of plastic porcelain clay and porcelain stone ore as the matrix and feldspar and timely as the raw materials, which are molded, dried and fired, mainly including ceramics for daily use, art and construction. Archaeological findings prove that China people invented pottery as early as the Neolithic Age (about 8000 BC). Agricultural production in the late primitive society made the ancestors of China people live a relatively fixed life, and there was an objective demand for pottery. In order to improve the convenience and quality of life, people gradually burn pottery by firing clay.
With the development of modern science and technology, many new ceramic varieties have appeared in the last hundred years. They no longer use or rarely use traditional ceramic raw materials such as clay, feldspar and timely, but use other special raw materials, and even expand to the scope of non-silicate and non-oxide, and many new technologies have emerged. The literature of the United States and some European countries has understood the word "ceramics" as a general term for various inorganic non-metallic solid materials. So the meaning of ceramics has actually gone far beyond the narrow traditional concept in the past.
Up to now, the definition of ceramics can be summarized as follows: ceramics are a certain type of technological rocks formed by certain physical and chemical processes at a certain temperature and atmosphere with aluminosilicate minerals or some oxides as the main raw materials. The surface can be glazed or unglazed, and some ceramics are translucent to varying degrees. The whole is composed of one or more kinds of crystal or amorphous cements, pores or clinker inclusions and other microstructures.
Ceramic industry is one of the main branches of silicate industry and belongs to the category of inorganic chemical industry. However, modern science is highly integrated and interpenetrating. From the analysis of the manufacturing process of the whole ceramic industry, it is complicated and involves a wide range, which is obviously not summarized by the simple inorganic chemistry theory.
There are many kinds of ceramic products, and their chemical composition, mineral composition, physical properties and manufacturing methods are often close to each other without obvious boundaries, but there are great differences in application. Therefore, it is difficult to generalize into several systems, and there are different opinions on detailed classification. So far, there is no unified classification method in the world. Commonly used from different angles have the following two categories:
(1) Classification according to different purposes
1. Household ceramics: such as tableware, tea sets, jars, jars, pots, pots, plates, dishes, bowls, etc.
2. Art ceramics: such as vases, sculptures and furniture.
3. Craft ceramics: vases, flower pots, flower arranging packages, lamp holders, garden ceramic resin craft vessels, etc.
4. Industrial ceramics: refers to ceramic products used in various industries. It is divided into the following six aspects:
(1), building sanitary ceramics: such as bricks, drains, tiles, exterior wall tiles, sanitary ware, etc. ;
(2) Chemical stoneware: acid-resistant bricks and ashes of acid-resistant containers, pipelines, towers, pumps, valves and enamel reaction tanks used in various chemical industries;
(3) Chemical porcelain: porcelain crucible, evaporating dish, burning boat, grinding body, etc. Used in chemical laboratory;
(4) Electric porcelain: used as insulator on high and low voltage transmission lines in power industry. Bushings for motors, post insulators for low-voltage appliances and lighting, and
Insulator for telecommunication, insulator for radio, etc. ;
(5) Refractory materials: refractory materials for various high-temperature industrial furnaces;
(6) Special ceramics: all kinds of special ceramic products left over from modern industry and cutting-edge technology, including high-alumina porcelain, magnesia porcelain, titanium-magnesium porcelain, zircon, etc.
Stone porcelain, lithium porcelain, magnetic porcelain, cermet, etc.
(2) According to the density of raw materials and green bodies, it can be divided into:
Brick or terracotta, clay, stone products, semi-porcelain, and even porcelain (130 relay), the raw materials are coarse to fine, and the green body is coarse to porous, gradually becoming dense, and the sintering temperature is gradually increasing.
Pottery is the most primitive and lowest pottery, generally made of fusible clay. In some cases, clinker or sand can be added to clay to reduce shrinkage. The firing temperature of these products varies greatly, depending on the nature and quantity of impurities contained in the chemical composition of clay. If the porosity of bricks and tiles made of it is too high, the frost resistance of the green body is not good, and the mortar is not easy to cross, so the water absorption should generally be kept between 5 ~ 15%. The color of the green body after firing depends on the content of colored oxides in clay and the firing atmosphere. When fired in the oxidation flame, it is mainly yellow or red, and when fired in reducing flame, it is mainly cyan or black.
The blue bricks in China's building materials are made of yellow or red clay containing fe2o 3. When the fire stops, they are calcined in reducing flame to reduce Fe2O3 to FeON and blue. Pottery can be divided into two types: ordinary pottery (cmmon) and fine pottery. Ordinary pottery refers to products with porous coloring bodies such as pottery pots, jars, altars, urns and refractory bricks. The water absorption of the green body of fine pottery is still 4 ~ 1.2%, so it is transparent and opaque, and it is generally white with color. Glazes are mostly fusible glazes containing lead and boron. Compared with stoneware, there is less flux, and the sintering temperature does not exceed 1300℃, so the green body is not fully sintered; Compared with porcelain, it has lower requirements for raw materials, greater plasticity and lower firing temperature. It is not easy to deform, and can simplify the processes of product forming and filling. However, the mechanical strength and impact strength of fine pottery are less than porcelain and stoneware, and its glaze is softer than the above products. When the glaze layer is damaged, the porous body is easy to be polluted, which affects the hygiene.
Fine pottery can be divided into clay, calcareous, feldspar and clinker according to different body components. Clay pottery is close to ordinary pottery. Lime fine pottery uses limestone as flux, and its production process is similar to that of feldspar fine pottery, but its quality is not as good as that of feldspar fine pottery, so it has been rarely produced in recent years and replaced by feldspar fine pottery. Feldspar fine pottery, also known as hard fine pottery, takes feldspar as flux. It is the most perfect and widely used pottery. In modern times, many countries have used it to mass-produce daily tableware (cups, plates, etc.). ) and sanitary pottery instead of expensive porcelain. Hot material fine pottery is to add a certain amount of clinker to the fine pottery blank to reduce shrinkage and avoid waste. This kind of blank is mostly used for large and thick tire products (such as bathtub, washbasin, etc.). ).
In ancient books in China, stoneware was called "stone tire porcelain". Its green body is dense and completely sintered, which is very close to porcelain. But there is no vitrification, and the water absorption rate is still below 2%. The green body is opaque and white, and most of them are allowed to develop color after firing, so the requirements for the purity of raw materials are not as high as those of porcelain, and raw materials are easy to obtain. Stoneware has high strength and good thermal stability, which is very suitable for modern mechanized washing, and can successfully survive the sudden change of temperature from refrigerator to oven. In the international market, due to the development of tourism and the socialization of diet, the sales of stoneware are larger than that of pottery.
The green body of semi-porcelain is close to porcelain, but it still has 3-5% water absorption after firing (the water absorption of real porcelain is below 0.5%), so its service performance is not as good as porcelain, but better than fine pottery.
Porcelain is a higher stage of ceramic development. Its characteristic is that the green body is completely sintered and vitrified, so it is dense and impermeable to liquid and gas. The thin part of the tire is translucent, and the cross section is shell-shaped. It feels smooth when licked with the tongue and will not get stuck. Hard ceramics have the best properties among ceramics. Used to make high-grade daily utensils, electric porcelain, chemical porcelain, etc.
Soft porcelain has more flux, lower firing temperature, lower mechanical strength and lower thermal stability than hard porcelain, but it has high transparency and rich decoration, and is mostly used to make artistic display porcelain. As for sintered porcelain and bone porcelain, their firing temperature is similar to that of soft porcelain, and their advantages and disadvantages are similar to that of soft porcelain, so they should belong to the scope of soft porcelain. These two kinds of porcelain are difficult to produce (the plasticity and drying strength of the body are poor, and the deformation is serious when firing), so the production is not universal. Britain is a famous producer of cinerary porcelain, and Tangshan, China also produces cinerary porcelain.
Special ceramics are developed with the rapid development of modern electrical appliances, radio, aviation, atomic energy, metallurgy, machinery, chemistry and other industries, as well as cutting-edge science and technology such as computer, space technology and new energy development. The main raw materials used in these ceramics are no longer clay, feldspar and quartz, and some green bodies also use some clay or feldspar. However, pure oxides and raw materials with special properties are used, and their manufacturing processes and performance requirements are also different.