T. Kirihara et al., EFFECT OF REACTION SITES ON DECARBURIZATI ON RATE IN THE RANGE OF ULTRA-LOW CARBON CONCENTRATION UNDER REDUCED PRESSURE, Tetsu to hagane, 80(9), 1994, pp. 705-710
Theoretical and experimental studies were carried out to quantitativel
y understand the effect of reaction sites on the decarburization rate
of ultra low carbon steel. The decarburization rate was studied in a 3
0kg vacuum induction furnace by varying the areas of three reaction si
tes such as bath surface, steel melt-crucible interface and inner part
of molten steel. With the oxygen content of 400ppm, the ratio of the
decarburization rate at the bath surface to the overall one is largest
for [C] less-than-or-equal-to 27ppm, whereas the largest is that of t
he inner part of molten steel for [C] greater-than-or-equal-to 27ppm.
The fluiddynamic calculation of the flow pattern of CO bubbles nucleat
ed inside the molten steel of RH vacuum vessel made clear that a part
of CO bubbles near the down-leg was sucked into the ladle and dissolve
d into the steel melt without decarburization. The effect of each reac
tion site on decarburization rate in RH was calculated to be the same
tendency as that in the 30kg induction furnace.