Boiling

Boiling or retardation of boiling occurs at a certain ratio of silicon to carbon and working temperature. The VDG has carried out and published several investigations on this subject. According to the VDG manual, the start of the boiling process or retardation of boiling will be initiated at a ratio of Si to C of approx. 0.91 or 2% Si and 2.2% C and 1,510 °C. This condition should be avoided if possible, or gone through quickly, since boiling cannot be interrupted or stopped without negative effects on the melt. The addition of aluminium is the worst, yet most efficient solution, if delay can be expected to lead to serious damage. A sudden temperature reduction brought about by the addition of cooling scrap can also be sued successfully without negative effects on the composition of the melt.