On the Gas Absorption in Condensed Film Accompanied in Oxygen Determination of Steel by Vacuum Fusion Method

Abstract

Condensed elements in bath are evaporated during vacuum fusion, accomplishing the absorption of CO extracted from bath, and authors could exactly recognize through the use of the gas analyzer “Exhalograph” that high speed of pumping system is to be in avail for the decrease of above pheno-mena, as had already been presumed by many workers.
In addition, to investigate on the behaviour of condensed element during vacuum fusion the further experiments were carried out with pure iron added condensed elements such as Al, Mn and Cr, of which the results obtained showed that the origin of evaporation of condensed elements should be caused in. physical state of bath. The decrease of determined value of oxygen attributable to condensed elements, therefore, would occur when the amount of these elements in bath rise above allowing limit, and be reduced in bath constituted from Ni, in which the evaporation of condensed elements is considerably defended. Whereas complete determination of oxygen would be accomplished if the fluidity of carbon-saturated bath, which corresponds to the form of graphite, is less viscous, in spite of the amount of condensed elements, and the form of graphite was transformed to less viscous one with simultaneous addition of Ce, but not with bath added previously Ce, because the effect of Ce is not continued.