About the Equilibrium with Freeze-in Temperature Property Model

The Equilibrium with Freeze-in Temperature Property Model calculates equilibrium at the freeze-in temperature and evaluates the properties at a different temperature.

The assumption is that diffusion and phase transformations are negligible when changing from the freeze-in-temperature and, therefore, that the phase amounts and compositions of phases are kept at the evaluation temperatures.

Typically, the freeze-in occurs during cooling where equilibrium can be assumed above the freeze-in temperature. This is the default setting and the Equilibrium above freeze-in temperature checkbox is automatically selected for this model. Change this default setting (i.e. click to clear the checkbox) when the frozen structure should be evaluated at a higher temperature than the freeze-in temperature.

The electrical resistivity due to phase interface scattering is evaluated as the scattering constant times sum of the interaction between the volume fraction of all the phases. The default value for the constant is 4.0e-8 Ωm. The contribution to thermal conductivity is assumed to be related to that of electrical resistivity, following the Wiedemann-Franz law.

A selection of homogenization functions is available for the evaluation of thermal- and electric-properties. Thermal and electric properties depend on the microstructure and the geometrical representation of phases in the microstructure can be linked to different homogenization functions. The homogenization function is applied on thermal- and electrical-resistivity. The electric conductivity, thermal conductivity, and thermal diffusivity are evaluated from the resistivities.

This Property Model uses thermophysical properties that are included with some Thermo‑Calc databases such as the TCS Al-based Alloy Database (TCAL), which is used in the two examples included with your installation. For more information about the availability and the theory, see About Thermophysical Properties Data Parameters, Electrical Resistivity Model, and Thermal Conductivity Model.