Silicon Deoxidation Effect
Silicon reduces oxygen in the steel and prevents porosity. It increases strength and scale resistance, but too much silicon can lead to embrittlement.
Physical-chemical mechanism of action
Silicon reacts with oxygen in the molten steel and forms silicate. This process binds the oxygen and prevents it from escaping as pores in the weld.
Metallurgical relevance & risks when welding
The deoxidizing effect of silicon is crucial for weld quality. Too little silicon can lead to porosity, which impairs strength. Too much silicon (above approx. 0.40 %) can cause embrittlement and increased susceptibility to hot cracking.
Workshop practice & instructions
Make sure the silicon content in the steel is within the optimal range. For high-performance steels with high carbon content (e.g., HSS), a silicon content of 0.2 to 0.4 % is recommended. Monitor the deoxidation processes and adjust the additives if necessary.