About this Abstract |
Meeting |
2025 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Thermodynamics and Kinetics
|
Presentation Title |
Estimation of heat capacity of mixed oxides using polyhedron model |
Author(s) |
Jesus Alejandro Arias Hernandez, Sun Yong Kwon, Elmira Moosavi-Khoonsari |
On-Site Speaker (Planned) |
Jesus Alejandro Arias Hernandez |
Abstract Scope |
The Neuman-Kopp rule is widely used in the CALPHAD community to estimate the heat capacities of stoichiometric compounds whose properties have not been experimentally measured. Despite its popularity, it has often shown rather poor predictability at high temperatures. This presentation introduces the polyhedron model for estimating high-temperature heat capacity. Unlike the Neumann-Kop rule, which assumes invariant thermodynamic properties of unit oxide components, the polyhedron model assumes unit polyhedra as constituents of mixed oxides. Consequently, heat capacity is estimated by summing the constituent polyhedra. The model also considers the effect of the second order transition on heat capacities by using the Landau theory. The heat capacities of Fe3Al2Si3O12, Na2Ti3O7, and NaAlSi2O6 estimated by the polyhedron model are presented in comparison with those predicted by the Neuman-Kopp rule and experimentally measured. This work expands the system to include TiO2, ZnO, and PbO-containing compounds, for which limited experimental information is available. |
Proceedings Inclusion? |
Planned: |
Keywords |
Computational Materials Science & Engineering, Other, Other |