Nitrogen alloying of carbon and stainless steels by gas injection

A model of nitrogen alloying of carbon or stainless steels by bottom nitrog en gas injection in converters or ladies has been developed. It combines a description of the local kinetics in terms of a mixed-control interfacial r eaction/liquid-phase mass transfer model and a hydrodynamics description of the plumes that constitute the active reaction zones. It has been validate d from special trials made in the converter and ladle at atmospheric pressu re or under vacuum for carbon steels and in the ladle for stainless steels with ultra high N contents.