Computer-aided simulations and calculations are an important part of materials technology research and development work. Since October 2024, the Thermo-Calc software package with the add-on modules DICTRA and TC-PRISMA in the Chair of Materials Engineering available.
The Thermo-Calc software package consists of various modules for the calculation of thermodynamic problems in multi-component alloy systems and the necessary material databases based on theoretical and experimental information. The calculation of the temperature-dependent phase fractions of alloys and their chemical composition with Thermo-Calc allows a deeper understanding of material-internal processes during production, heat treatment, processing and use. This enables targeted material development and increases the effectiveness and knowledge gained when carrying out experimental investigations.
The Chair of Materials Engineering has access to the databases for Fe-based alloys (TCFE13 and MOBFE8), which can be applied to all technically relevant steel and cast iron alloys.
With the help of Thermo-Calc can be used to
- temperature-dependent phase diagrams for complex alloys
- solubility limits, chemical composition and proportion of phases
- thermodynamic quantities (such as enthalpy, entropy, heat capacity, etc.)
- Transformation temperatures (solidus, liquidus or austenitisation temperature)
- solidification processes using the Scheil-Gulliver model
can be calculated and visualised. The change in the alloy through use under specific conditions, the addition of alloying elements or the reduction of accompanying elements is often the focus of the questions, which significantly influence the properties. In addition, the DICTRA and TC-PRISMA add-ons allow further simulations.
The diffusion module DICTRA enables the modelling of diffusion-controlled multi-component transformations. In addition to the thermodynamic database (TCFE13), a kinetic database (MOBFE8) is also used for this purpose, which provides information on the mobility of atoms in the relevant phases.
With DICTRA the following diffusion-controlled processes can be analysed:
- Microsegregation of alloys during solidification
- Homogenisation of alloys during heat treatment
- Growth or dissolution of secondary phases (carbides, nitrides or intermetallic phases)
- Temperature-dependent coarsening of precipitation phases
- Allotropic phase transformations (α-γ transformation in steel or α-β transformation of titanium alloys)
- Carburisation, nitriding and carbonitriding of high-temperature alloys
- Interdiffusion in heterogeneous composite materials
- Heat treatment and sintering processes
The precipitation module TC-PRISMA allows the simultaneous simulation of nucleation, growth (or dissolution) and coarsening of phases under any heat treatment conditions in complex multi-component and multi-phase systems. TC-PRISMA extends the functionality available in Thermo-Calc by enabling calculations related to precipitation.
With TC-PRISMA the following processes and parameters can be analysed:
- Nucleation, growth or dissolution and coarsening of precipitates
- Volume fraction and composition of excretions
- Nucleation rate and coarsening rate
- temporal development of the particle size distribution
- Average particle radius and number density
- Time-temperature precipitation diagrams
- Time-temperature-transformation diagrams
