At Sollac-Dunkerque, a characterization of the present RH process for
production of ultra-low carbon steels was performed. A study of the de
carburization kinetics was possible thanks to gas analysis, As a first
result, the treatment time can safely be reduced by three minutes, Mo
reover, in the ultra-low carbon range, the decarburization kinetics is
strongly slowed down due to the suppression of the boiling mechanism.