Casting is a kind of metal hot processing technology which has been mastered earlier by human beings. It has a history of about 6000 years. China has entered the full bloom period of bronze casting about 1700 to 1000 B.C., which has reached a high level in technology. The Chinese weighs 875 kg of Simuwu quadripod, Ceng Houyi statue in the Warring States period, light microscope of the Western Han Dynasty, is the representative of the ancient casting products. Most of the early castings are tools or utensils in agricultural production, religion, life and so on, with a strong artistic color. At that time, the casting process was developed in parallel with the pottery making process, which was greatly influenced by the pottery. So, what is casting? Casting is the process of melting the solid metal into a mold with a specific shape in a liquid state. The cast metal has: copper, iron, aluminum, tin, lead and so on. The common mold material is the raw sand, clay, water glass, resin and other auxiliary materials. The cast types of special casting include: melt mold casting, EPC, metal casting and ceramic casting. (the original sand include: quartz sand, zircon sand, iron ore, magnesite, magnesium olivine sand, kyanite sand, graphite sand, sand etc.) early casting is mostly tools or appliances and agricultural production, religion, life and art, strong color.
At that time, the casting process was developed in parallel with the pottery making process, which was greatly influenced by the pottery. In 513 BC China cast out of the world's first recorded in ductile cast iron - casting Ding Jin, weighing about 270 kg. Iron castings were also produced in Europe before and after eighth Century. The appearance of cast iron widened the application range of the castings. For example, in the 15~17 century, Germany, France and other countries have laid a lot of cast iron pipes for drinking water for the residents. After the industrial revolution in eighteenth Century, steam engine, textile machinery and railway industry rose, and the casting entered into the new era of big industry service. The foundry technology began to develop greatly. In twentieth Century, the development of casting speed, it is one of the important factors of product technology requirements of casting better mechanical and physical properties, and still have good machining performance; another reason is the development of machinery industry itself and other industries such as chemical engineering, instrumentation, foundry industry to create a favorable material conditions.
For example, the development of testing means ensures the improvement and stability of the casting quality and provides conditions for the development of the casting theory. The invention of electron microscope helps people to go deep into the microscopic world of metals, explore the mystery of metal crystallization, study the theory of metal solidification, and guide casting production. In this period of time to develop a large number of excellent performance, the new casting metal rich varieties, such as nodular cast iron, malleable cast iron can be welded, ultra low carbon stainless steel, aluminum, aluminum silicon, aluminum magnesium alloy, titanium, nickel base alloy, and invented a new process of inoculation treatment of ash cast iron, cast more widely adaptability. After 50s, the wet sand high pressure molding, chemical hardening sand molding and core making, negative pressure molding (see vacuum casting) and other special casting, blasting (see new technology, casting cleaning) the casting has very high precision of shape and size and good surface smoothness, foundry working conditions health and environment have greatly improved. In the great progress of the foundry industry since twentieth Century, the two new processes, such as the inoculation of gray cast iron and the molding of chemical hardened sand, have special significance.
These two inventions have broken through the traditional way which lasted for thousands of years, opened up a new field for casting technology, and had a great influence on improving the competitive ability of castings. Many pieces of copper casting structure and the main components are casting for the blank, and the quality of copper, copper casting precision is closely related to the quality of life of the whole machine quality, precision, persistence has a crucial influence. Copper casting and can be used in the valve box, injection molding machine, water pipes etc...
There are a variety of classifications for castings: casting steel, cast iron, cast copper, cast aluminum and copper castings according to the different materials used in the casting. And each type of castings can be further red by its chemical composition or metallographic structure. As cast iron can be divided into the gray iron, malleable iron, alloy cast iron; cast molding method according to different, can put into ordinary casting sand casting, metal casting, die casting, ceramic mold casting, Electroslag Remelting Casting, casting etc.. Among them, ordinary sand castings are most used, accounting for about 80% of the total output of the castings. Nonferrous metal castings such as aluminum, magnesium and zinc are mostly castings.
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