Metalstrade Ltd is engaged in the import/export of Grey Cast Iron. It is usually refers to cast iron but identifies a large group of ferrous alloys, which solidify with a eutectic. Grey cast iron is named after its grey fractured surface, which occurs because the graphitic flakes deflect a passing crack and initiate countless new cracks as the material breaks. Silicon is essential to making grey cast iron as opposed to white cast iron. When silicon is alloyed with ferrite and carbon in amounts of about 2 percent, the carbide of iron becomes unstable. Silicon causes the carbon to rapidly come out of solution as graphite, leaving a matrix of relatively pure, soft iron. Weak bonding between planes of graphite lead to a high activation energy for growth in that direction, resulting in thin, round flakes. Some of the features are:
- The graphite content also offers good corrosion resistance.
- The exceptionally high speed of sound in graphite gives cast iron a much higher thermal conductivity.
- The grey cast iron has less tensile strength and shock resistance than steel.
- High thermal conductivity and specific heat capacity.