Iron has been around and part of day-to-day lives for centuries. The metal has various uses, which include farming to war weapons. Blacksmiths came up with ways to change iron properties and make the material into tools. Today the process is known as a foundry. So what are cast iron foundries and the different types of cast irons?
What is cast iron foundry?
It refers to an industrial installation that makes iron casting or molded items. The factories have multiple steps to complete the process. It includes melting the iron stock in furnaces and pouring the molten metal into molds.
After cooling the metal, the casting is removed from the mold, washed, and gets rid of all casting defects. The foundries can produce small items weighing a few ounces and large items weighing several tonnes. There are various grades or types of iron used to make the pieces, including Nodular or ductile and gray iron.
Nodular or ductile iron
Ductile iron acquires its unique properties via the addition of magnesium into the alloy. The magnesium makes it easy for the graphite to form a sphere shape, unlike the flakes of gray iron. However, composition control is vital in the manufacturing process.
Small quantities of impurities like sulfur and oxygen react with magnesium, affecting the shape of graphite molecules—distinctive grades of ductile iron which form by working the microcrystalline structure near the graphite spheroid. Cast iron foundries in India achieve this via the casting process or heat treatment used as a downstream processing step. Ductile iron changes form on impact, making it good casting iron.
Gray iron
One characteristic of gray iron is the flake shape of the graphite molecules in the metal. When the metal ruptures, a crack occurs along with the graphite flakes, which gives it a gray color. YOu can control the size and matrix form of the graphite flakes during production by altering the cooling rate and composition.
Gray iron is not like ductile iron and has a low tensile strength, although it’s a better thermal conductor. In addition, it has a significant level of vibration damping that makes it easier to machine.
Foundries use three types of iron for their production. As a result, they can produce various casting sizes and different qualities.
