화학공학소재연구정보센터
Materials Science Forum, Vol.426-4, 963-968, 2003
The dependence of activity coefficient on intensive thermodynamic parameters in a liquid Fe-N-V alloy
The article presents the methodology and results of experimental studies on the solubility of nitrogen in liquid Fe-V alloys. Tests were carried out using the levitation metal melting technique. Liquid alloys of Fe-V ([%V](wt.%) 1.5; 2.5; 4,0; 5.8; 7.8; 12.2; 45%) were saturated with nitrogen at temperatures of 2073, 2173, 2273 K. The partial pressure of nitrogen was varied in the range 0.001-2.5 MPa. The experiment involved melting a I g specimen in an electromagnetic field generated by a levitation coil, filling the reaction chamber with nitrogen up to the required pressure and heating the specimen up to a preset temperature. High nitrogen concentrations were obtained in the samples due to the formation of high nitrogen partial pressures in the gaseous phase in the reaction chamber. In such conditions, all interactions of nitrogen in the alloy tested could be disclosed, namely: nitrogen-vanadium, nitrogen-nitrogen, and nitrogen-nitrogen-vanadium interactions. The results of the tests showed a nonlinear dependence of the activity coefficient, f(N), not only on vanadium content in the alloy, but also on nitrogen content in it. Using the experimental data and the findings of the previous study on the liquid Fe-N alloy, temperature relationships of inter- and self-reaction parameters have been determined.