About Thermophysical Properties Data Parameters

The Thermo‑Calc databases have a variety of properties data included such as molar volume, thermal conductivity, dynamic and kinematic viscosity, thermal resistivity, electrical resistivity, and surface tension. These properties data are being integrated into databases as each new version of a database is released.

Availability of properties data is dependent on both the database and its version. Some information is specific to use in Console Mode. There is more information also available for Graphical Mode, TC‑Python, or TC-Toolbox for MATLAB® for each of the databases where the properties data is included. More advanced information is also contained in the Database Manager User Guide PARAMETER section.

To determine if the database you are using has this properties data, search the help (press F1) to review the technical information. The availability of properties data is also included with the Database Overview document available on the Thermo‑Calc website.

Parameters, Functions, and Variables and Thermophysical Properties Models, Data, and Variables

The so-called classic syntax is used in the examples below. It can be used in Console Mode or when using the APIs, e.g. TC-Python or TC-Toolbox for MATLAB®. Graphical Mode in Thermo‑Calc has readable names for all of these.

Below is a summary of the available thermophysical parameters and variables for the databases when working in Thermo‑Calc. There are differences when you are working in Console Mode versus Graphical Mode as well as if you use an SDK such as TC‑Python or TC-Toolbox for MATLAB®.

Property (and Graphical Mode Variable Name) Model Parameters Variables to Show or Plot in Console Mode or the SDKs (TC‑Python, or TC-Toolbox for MATLAB®)***

Molar volume

V0, VA

VM for a system VM(PHI) for phase PHI

Electrical conductivity

ELQ**

ELCD for a system ELCD(PHI) for phase PHI

Electrical resistivity

ELRS, ESPD

ELRS for a system ELRS(PHI) for a phase PHI

Thermal conductivity

THCD

THCD for a system THCD(PHI) for phase PHI

Thermal resistivity

 

THRS for a system THRS(PHI) for phase PHI

Thermal diffusivity

 

THDF for a system THDF(PHI) for phase PHI

Surface tension

SIGM, XI*

 SURF(LIQUID)

SURF(ION)**

Dynamic viscosity

VISC

DVIS(LIQUID)

DVIS(ION)**

Kinematic viscosity

 

 KVIS(LIQUID)

KVIS(ION)**

* XI is not used in the TCOX database (all versions). As of 2023b it is also not used starting with the following versions of these databases: TCFE13, TCNI12.1, TCTI5.1, TCNOBL3, TCPMAG2, and TCCU6. As of 2024a, TCMG7, TCAL9, and TCHEA7. As of 2024b, TCSLD5.

** ION is used in the TCS Metal Oxide Solutions Database (TCOX)

*** The examples listed for the SDKs are using Console Mode syntax. The quantities can also be accessed in both ThermodynamicQuantity and ScheilQuantity classes. See the various model descriptions or the SDK help for details.

Viscosity of the Metallic Liquids Model

Viscosity of the Ionic Liquids Model

To use this model, the database parameter VISC is needed. It can be used for liquids.

  • Dynamic viscosity (DVIS)
  • Kinematic viscosity (KVIS)

Examples in Console Mode:

  • In POLY module: show dvis(liquid)
  • Set as plot variable: set-diagram-axis y kvis(liquid)

Thermal Conductivity Model

To use the thermal conduction parameters, the database parameter THCD is needed. The other two related properties are derived from THCD. These properties can be obtained for a phase or for the whole system.

  • Thermal conductivity (THCD)
  • Thermal diffusivity (THDF)
  • Thermal resistivity (THRS)

Examples in Console Mode:

  • In POLY module: show thcd
  • Set as plot variable: set-diagram-axis y thdf(fcc_a1)

Electrical Resistivity Model

To use the electric properties parameters, the database parameter ELRS is needed. ELCD is derived from that. These properties can be obtained for a phase or for the whole system.

  • Electrical conductivity (ELCD)
  • Electrical resistivity (ELRS)

Examples in Console Mode:

  • In POLY module: show elcd
  • Set as plot variable: set-diagram-axis y elrs(fcc_a1)

Electrical Conductivity for Ionic Liquid Model

To use the electric properties parameters, the database parameter ELQ is needed. The model parameters are the activation Gibbs energy of end-members and excess activation Gibbs energy.

  • Electrical conductivity of molten slags ELCD(IONIC)
  • Electrical resistivity of molten slags ELRS(IONIC)

Surface Tension of Metallic Liquid Alloys Model

Surface Tension Model for Oxide Slag

Surface tension for liquids can be calculated if the database contains the two database parameters SIGM and XI. From these, the surface energy is calculated:

  • Surface energy (SURF)

XI is not used in the TCS Metal Oxide Solutions Database (TCOX)

Examples in Console Mode:

  • In POLY module: show surf(liquid)
  • Set as plot variable: set-diagram-axis y surf(liquid)