Cast iron is a ferro-carbon alloy with a purport of carbon between 2.11% and 6.69%. It is obtained from the transformation of haematite in blast furnaces. During the solidification the carbon separates from the metallic mass and is presented as graphite which is dispersed uniformly under the form of thin layers.
- strong workability with machine tools;
- good resistance to use and to thermal stress;
- good castability.
- components exposed to a low level of mechanical stress;
- industrial sector;
- rail and tramway sectors;
- fireplace and accessories sector;
- nautical sector;
- artistic casting.
The influence of the binding elements
- Silicon: aids the formation of graphitic carbon; it improves its workability with machine tools; it lowers the casting temperature rendering the alloy more fluid.
- Manganese: favours the formation of carbon under the form of cementite; it carries out a de-sulphurizing action; it induces an increase in the breaking load and hardness and raises its level of hardenability.
- Phosphorous: influences the temperature at the end of the solidification and increases the castability of the alloy; it considerably reduces the mechanical properties of resistance and resilience.
- Sulphur: interferes with the formation of the graphite; it induces suction and blow-holes; it influences the mechanical and technological properties in a negative way.
- Molibdenium: aids the the hardenability; it reduces the possibility of cracks and distortions.
- Nickel: decreases the sensitivity to thickness; It improves its resistance to use.
- Chrome: improves the mechanical resistance; it reduces the critical speed of cooling thus improving its hardenability.