Secondary metallurgic process in which calcium-containing compounds are blown into the ladle to reduce the contents of sulfur and non-ferrous inclusions.
CaSi is an universal deoxidation and desulfurization agent (see Calcium silicon). During deoxidation and desulfurization, exclusively the calcium becomes active. The silicone serves as carrier element. It causes a reduction of the high steam pressure of the pure calcium during steel production and is dissolved in the steel.
The products that form due to the reaction of the calcium are liquid in the melt and can be coagulated to larger units to separate them. Particularly calcium aluminates have optimum separation properties. For this reason, combined Al-CaSi deoxidation is preferably used if aluminum can be used (see also Calcium aluminum). Calcium acts as a modifier for the solid alumina inclusions. This way, low contents of dissolved oxygen are achieved at quick separation of the primary deoxidation products. Foirmation of alumina clusters is prevented.
The reduced contents in solid deoxidation products improve the castability of the melt and the surface quality during die casting and continuous casting.