Abstract
A kinetic study has been made on the nitrogen desorption from inductively stirred iron-chromium melts with 6.527.5%Cr under reduced pressures at 1 600°C.
The rate of nitrogen desorption under the pressure of 8×102 Pa is essentially controlled by the mass transfer of nitrogen in liquid and gas phases as well as the chemical reaction at the liquid-gas interface, although the rate is mainly controlled by the chemical reaction at the interface.
In case of 17%Cr melt containing 50 ppm of oxygen at around 70 ppm of nitrogen in the melt under the pressure of 8×102 Pa, the interfacial resistance is 5 times larger than the resistance of mass transfer in the liquid phase, and the interfacial resistance is 10 times larger than that in the gas phase.
It is suggested that the apparent adsorption coefficients of O and S increase with increase of Cr content in the melt.
