'Silicon metal' is the term used to describe alloys containing silicon as the main alloying element, which are often used in foundries. Adding silicon to these alloys improves flowability, hot cracking resistance and tightness. Other elements, such as copper and magnesium, are added to improve the strength of the material during heat treatment.
Silicon metal has a number of roles in steel production, including deoxidation. Silicon is a great deoxidising agent that can effectively join with oxygen in molten steel to form SiO2 slag, which reduces the oxygen content of the steel.
b) Increasing melting point: Adding silicon metal can slightly increase the melting point of steel, which is useful in some high-temperature applications.
c) Promoting graphitisation: In cast iron, silicon metal can encourage graphite formation, affecting the structure and properties of the iron.
