COMMODITY OVERVIEW

Cast iron is a group of iron-carbon alloys with a carbon content more than 2%.[1] Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its colour when fractured: white cast iron has carbide impurities which allow cracks to pass straight through, grey cast iron has graphite flakes which deflect a passing crack and initiate countless new cracks as the material breaks, and ductile cast iron has spherical graphite "nodules" which stop the crack from further progressing.

Carbon (C) ranging from 1.8 to 4 wt%, and silicon (Si) 1–3 wt%, are the main alloying elements of cast iron. Iron alloys with lower carbon content are known as steel.

Cast iron tends to be brittle, except for malleable cast irons. With its relatively low melting point, good fluidity, castability, excellent machinability, resistance to deformation and wear resistance, cast irons have become an engineering material with a wide range of applications and are used in pipes, machines and automotive industry parts, such as cylinder heads, cylinder blocks and gearbox cases. It is resistant to damage by oxidation

There are various types of metal casting, cast iron and cast steel are the most common types of casting. While cast iron includes grey cast iron, ductile cast iron and malleable cast iron, cast steel includes alloy steel and carbon steel casting. Iron casts have carbon content of more than 2 percent. On the other hand, steel casting products less than 2 percent carbon content. The chemical properties of cast iron and cast steel do not vary largely. However, they have different physical properties.

• Alloying elements

• Grey cast iron

• White cast iron

• Malleable cast iron

• Ductile cast iron

FEATURES AND BENEFITS

High machinability, good wear resistance as well as good vibration damping. It can withstand greater load and has a good degree of resistance against corrosion. It, however, has low tensile strength and elongation properties. It is used in manufacture of cylinder blocks, pistons, gear boxes, knives, table wheels, pipes, valves, etc.

They have high strength, high heat-resistance and toughness. They are used in a wide range of industries: engineering, agriculture, automotive, road and construction, etc. the production of cast iron is more complex and expensive than grey cast iron. They also have more casting defects than grey cast iron.

Cast steel is highly flexible. Hence, it can be used to create parts or products of complex shape with hollow cross sections. It can be cast with a wide range of chemical composition that can be adapted according to the specific requirements of the product. By varying the heat treatment, the mechanical properties and workability and wield ability of the cast steel can vary.