Reassessment of AlN(s)=<u>Al</u>+<u>N</u> Equilibration in Liquid Iron

Thermodynamics of Nitrogen Solubility and AlN Formation in Multi-Component High Mn Steel Melts

“…Table 5 summarizes the interaction parameters determined in the present study as well as in the author's recent studies. 5,7,8,14,24) Therefore, the nitrogen solubility in multicomponent Fe-Mn-Si-C-Al alloy melts of various compositions can be calculated by the following relation obtained from Eq. (3): In order to check the validity of interaction parameters determined in the present study, a verification experiment was carried out by measuring the N solubility in Fe-25% Mn-0.3% Si-0.6% C-Al melt which is a typical TWIP steel composition.…”

Thermodynamics of Nitrogen in Fe-Mn-Al-Si-C Alloy Melts

“…[87] However, it was found that the Gibbs free energy from JANAF tables was rather positive to reproduce the AlN solubility product data in liquid iron. [5,45,46,73,[79][80][81][82] For example, the Gibbs energy of formation of AlN was calculated from AlN solubility product data by Paek et al [91] and Evans and Pehlke [81] using the activity coefficient of Al and N in this study, and plotted in Figure 9. The standard enthalpy of formation of AlN from Al(l) and ½ N 2 (g) was determined by the direct nitridation (À320.0 ± 0.8 kJ/mol) [92] and the combustion calorimetry (À316.3 ± 1.7 kJ/mol).…”

Thermodynamics of AlN Formation in High Manganese-Aluminum Alloyed Liquid Steels

“…Therefore, the effect of oxygen on aluminum and nitrogen was assumed to be negligible. In the authors' recent studies, 9,10) the thermodynamics of Fe-Al-N and Fe-Mn-N melts were studied as a function of temperature. The values of log KAlN and the interaction parameters used in Eq.…”

“…In order to control the formation of AlN inclusions based on the supersaturation of those alloying elements during cooling and casting of liquid steels, it is essential to have accurate thermodynamic data of those elements in liquid steels as a function of melt temperature. In the authors' recent studies, 8,9) the thermodynamics of FeAl-N and Fe-Al-N-AlN systems was studied using the metal-gas-nitride equilibration technique in the temperature range from 1 823 to 1 973 K. The effect of manganese on the nitrogen solubility in Fe-Mn-N and Fe-Mn-Al-N melts was also studied. 10) In the present study, the effect of manganese on the AlN formation in high Mn-Al alloyed liquid steels were determined over wide ranges of manganese content and temperature.…”