semi-killed steel

In semi-killed steel, the aim is to produce metal free from surface blowhole and pipe.

The yield of rimmed and capped steel is slightly better than that of semi-killed steel.

It produces various Killed and Semi-Killed steels.

Semi-killed steel is mostly deoxidized steel, but the carbon monoxide leaves blowhole type porosity distributed throughout the ingot.

Since pipe cavities are minimized, semi-killed steels are usually cast in big-end -down molds without hot-tops.

Semi-killed steel is commonly used for structural steel with a carbon content between 0.15 to 0.25% carbon, because it is rolled, which closes the porosity.

During solidification of semi-killed steel, gas is evolved in the body of the ingot, tending to compensate in part or entirely for the shrinkage accompanying solidification.