Method for manufacturing a steel ingot

A method for manufacturing a steel ingot in a casting arrangement comprising a vacuum vessel;

• an ingot mold arranged within the vacuum vessel;
• and a stirrer arranged to stir liquid steel in the ingot mold, the method comprising the steps of:
• providing a liquid steel melt;
• filling the ingot mold with the liquid steel melt;
• applying a reduced pressure within the vacuum vessel;
• and
• allowing the liquid steel melt to at least partially solidify at a reduced pressure into an ingot, wherein the liquid steel melt is stirred within the ingot mold at a reduced pressure during at least a portion of solidification of the steel melt;
• wherein
• the ingot mold is manufactured of steel or cast iron;
• the liquid steel melt is Fe-based and comprises a predetermined amount of carbon;
• during stirring, incidental impurity elements in the form of oxides are reduced by carbothermic reaction in which oxygen in the oxides and carbon in the steel melt form carbon monoxide;
• the step of providing the liquid steel melt includes manufacturing the liquid steel melt outside of the vacuum vessel;
• and
• the pressure within the vacuum vessel is ≤1 mbar.