How cast iron is obtained?
The process of obtaining cast iron is divided into two stages :
In the first stage, cast iron is produced from pig iron.
At a temperature of 1100-1300 degrees Celsius molten pig iron is poured into a ladle, where it is heated to 1200-1300 degree Celsius, then the composition of the molten metal is adjusted by adding alloys (manganese and silicon) and pouring impurities (slag). The resulting melt is poured into molds. By cooling the molds, we obtain a permanent cast iron.
The second stage consists in removing casting defects and impurities: sand, slags, gas cavities (with flame treatment), shrinkage cavities (by welding or filling with material with thermal expansion close to cast iron).
The raw material used to manufacture cast irons include pig iron, scrap steel, limestone, coal and coke. Then they are melted in a furnace at a high temperature and poured into the molds to get the desired shape. The entire process of casting involves remelting of pig iron, adding of some scrap steel to it and melting it again all over again.
How cast iron is produced?
In the production of cast iron, the iron is melted in a furnace—either a blast furnace or an electric-arc furnace—and poured into molds to produce such products as machine parts and cooking utensils. The molten iron can be poured directly into molds, or it can be mixed with scrap and charged into electric furnaces.
The first step in making cast iron is to melt the iron ore in a furnace. The molten iron is then mixed with slag, usually limestone and dolomite, which forms a slag that floats on top of the liquid pig iron. The pig iron is removed from the furnace and broken down into smaller pieces by a machine called a pig breaker. After this step, it is ready for use in casting.
How cast iron is manufactured?
Cast iron is a hard, brittle alloy of iron and carbon that can be readily cast in a mold and contains a higher proportion of carbon than steel does. Carbon content typically ranges from 1.7 to 4.5 percent by weight, but cast irons with more carbon are considered too brittle for most uses. Alloying elements such as silicon and manganese are also added in small amounts to improve the casting characteristics of the molten metal.
Cast iron is produced by melting pig iron, which is the product of smelting iron ore in a blast furnace, together with coke and limestone. In the United States the principal raw material used for making pig iron is taconite, a low-grade iron ore found in large quantities in certain areas of the country.
The process by which pig iron is made into cast iron is known as ferroalloying. The molten cast iron from the blast furnace is mixed with scrap steel and melted again to remove most of its carbon content through oxidation (a process called decarburization).
The amount of decarburization depends on the desired properties of the final product, which may vary according to its intended use. For example, castings that will be subjected to heavy loads or stress during their service life require very high
What cast iron made of?
Cast iron is made by remelting pig iron, often along with substantial quantities of scrap iron, and often with the addition of other elements, for example scrap steel.
The liquid iron is cast, or poured and hardened, into crude ingots called pigs, which are subsequently remelted and cast into moulds in a foundry to form more useful sizes and shapes of iron.
The quality of the metal used for these products depends on the condition of the raw materials used in their manufacture.
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