In the past, ordinary cast iron products have been cleaned up due to the presence of defects such as air holes, sand holes, slag entrapment, cracks and fissures. Cast iron profiles have good strength, density, tensile, decompression and wear resistance. Cast iron profiles are characterized by smooth surfaces, high dimensional accuracy, and small machining allowance. It is characterized by excellent mechanical properties, a combination of high strength and high toughness as well as good fatigue resistance.
Gray Cast Iron
Higher carbon content (2.7% ~ 4.0%), carbon is mainly in the form of flake graphite, the fracture is gray, referred to as gray iron. Low melting point (1145 ~ 1250 ℃), solidification contraction is small, compressive strength and hardness close to carbon steel, and good shock absorption. Used in the manufacture of machine tool beds, cylinders, boxes, and other structural parts.
White Cast Iron
Carbon and silicon content is low, carbon mainly in the form of carburized form, the fracture is silver-white. Shrinkage during solidification, easy to produce shrinkage holes and cracks. High hardness, brittle, can not withstand impact load. Mostly used as malleable cast iron blanks and production of wear-resistant parts.
Malleable Cast Iron
Obtained by annealing white cast iron, graphite is flocculent distribution, referred to as tough iron. Its organizational properties are uniform, wear-resistant, good plasticity, and toughness. Used in the manufacture of complex shapes, can withstand strong dynamic load parts.
Ductile Iron
Gray cast iron by spheroidization treatment, the precipitation of graphite is spherical, referred to as ductile iron. Than ordinary gray cast iron has higher strength, better toughness, and plasticity. Used in the manufacture of internal combustion engines, automobile parts, and agricultural implements.
Alloy Cast Iron
Ordinary cast iron by adding the appropriate amount of alloying elements (such as silicon, manganese, phosphorus, nickel, chromium, molybdenum, copper, aluminum, boron, vanadium, tin, etc.) to obtain. Alloying elements to make changes in the matrix organization of cast iron, to have the corresponding heat-resistant, wear-resistant, corrosion-resistant, low-temperature resistant, or non-magnetic properties. Used in the manufacture of mining, chemical machinery and instruments, meters, and other parts.
Ductile iron bars, cast iron profiles, and horizontal continuous casting, through the spheroidal graphite obtained by hybridization and pregnancy treatment, effectively improve the mechanical properties of cast iron, especially improving the plasticity and toughness, to get higher than carbon steel… The ductile agent’s role in ductile iron can promote graphite crystallization into spheroidal, conducive to getting spherical graphite, after hybridization of ductile iron strength is substantially higher than gray cast iron, and toughness is better than malleable iron, effectively improves the mechanical properties of ductile cast iron, especially improve the ductile iron plasticity and toughness, to make the cast iron to get a higher strength than carbon steel. To make the graphite crystallization in cast iron become spherical and additives added to the liquid iron is called spheroidal agent. Magnesium has a strong spheroidal ability of the element, rare earth spheroidal action is relatively smooth, and can be independent of other anti-appetizing elements. Calcium acts smoothly, but the spheroidal ability is weak, adding a large amount of calcium metal is easy to oxidize, and can not be used alone.