Abstract
The solubility of nitrogen in liquid iron was studied at temperature from 1580° to 1730°C by both the SIEVERTS' method and a sampling method. By improving the methods, the results obtained in the temperature range agreed with each other within the experimental errors. However, from the viewpoint of the temperature dependence of the solubility, the results obtained by the sampling method is more reliable on the solubility of nitrogen in liquid iron.
The results obtained in liquid iron by the sampling method is expressed as follows:
log K(_??_[%N]/√PN2)=-518/T-1.063±0.0004
ΔG°=237+4.85T±0.002T (cal/g-atm).
The study was extended to the iron alloys containing the group VIa elements at 1580°C by the sampling method. Though all elements of the group VIa were expected to decrease the solubility of nitrogen, oxygen showed the opposite effect on the solubility. The results obtained are expressed by log fjN as follows:
log fON=-0.12[%O]<0.12%O, log fSN=0.007[%S]<4%S
log fSeN=0.006[%Se]<4%Se, log fTeN=0.070[%Te]<0.6%Te.