thermo-Calc 2025a is a powerful thermodynamic software package developed by Thermo-Calc Software AB, released in June 2024. It leverages the CALPHAD (CALculation of PHAse Diagrams) method to compute phase equilibria, thermochemical properties, and phase transformations in multicomponent alloy systems. Widely used in materials science, metallurgy, aerospace, and energy sectors, it supports applications like alloy design, heat treatment simulations, and additive manufacturing process optimization. The software integrates with databases covering thousands of assessed systems for elements from H to Uut, enabling accurate predictions under varying temperature, pressure, and composition conditions.
As of October 2025, the current version is Thermo-Calc 2025.2 (build 174669-233), which includes further enhancements like improved simulation accuracy for Al-Si-Mg alloys in additive manufacturing. Users on active maintenance can upgrade seamlessly from 2024b for access to these updates.
Key Features
- Core Modules:
- Equilibrium Calculator: Solves complex multiphase equilibria with Scheil-Gulliver simulations for solidification paths.
- Diagram Generator: Interactive binary/ternary/multicomponent phase diagrams, including property contour plots.
- Property Model Library: Over 50 models for diffusion, viscosity, surface tension, and more, with steel-specific enhancements.
- Materials Design Module: High-throughput screening for alloy optimization using parallel coordinates plots.
- Additive Manufacturing (AM) Module: Weld simulations, printability assessments, and melt pool analysis.
- Databases: 20+ thermodynamic and mobility databases (e.g., TCFE for steels, TCNI for Ni-superalloys), plus kinetic add-ons like DICTRA for diffusion-controlled reactions.
- Integration: Supports TC-Python API for scripting, parallel computing, and export to CSV, Excel, or MATLAB.
- Visualization: Advanced 2D/3D plotting with export options for reports.
What’s New in Version 2025a (Released June 2025a)
This release focuses on advancements in manufacturing simulations, model accuracy, and usability:
- Additive Manufacturing Enhancements: Printability maps added to the AM Module for assessing alloy suitability; fluid flow integration in the keyhole weld model for more precise melt pool size predictions (demonstrated in five new examples).
- Steel Model Library Updates: New “Tempering time (s)” field in the Martensitic Steel Strength Model to account for time-dependent effects on tempered martensite strength.
- Parallel Calculations Fix: An update resolved issues with property models requiring TC-Python licenses when parallel processing is enabled (default setting).
- New Calculation Types: Expanded options in the Diffusion Module for multicomponent simulations.
- Database Additions: Six new or updated databases, including improvements for light alloys and high-entropy systems.
- Bug Fixes: Enhanced stability for large-scale optimizations and better handling of user-defined parameters.
