Equilipy for computing multicomponent-multiphase equilibria

equilipy is an open-source Python package for multicomponent-multiphase equilibrium calculations based on the CALPHAD (CALculation of PHAse Diagram) approach. Given a thermochemical database and input conditions (composition, pressure, and temperature), it computes the equilibrium phase configuration, amounts, compositions, and thermochemical properties. equilipy uses the Gibbs energy descriptions furnished by THERMOCHIMICA with the modified Gibbs energy minimization algorithm inspired by Eriksson[1] and de Capitani and Brown.[2]

User guide

Quick start

Quick installation

Core package:

pip install equilipy

Desktop GUI (adds the equilipy.gui command):

pip install 'equilipy[gui]'

MPI helpers for clusters:

pip install 'equilipy[hpc]'

Database availability

Equilipy reads two thermochemical database formats:

Format	Reader	Notes
ChemSage/FactSage `.dat`	`eq.read_dat(path)`	Legacy (7.3) and modern (8.3+) dialects are auto-detected, including validated MQM/SUBG/SUBQ solution-model canaries.
Thermo-Calc style `.tdb`	`eq.read_tdb(path)`	CEF solution models, magnetic contributions, and order/disorder (`DIS_PART`) are supported.

An example Al-Cu-Mg-Si database (assessments from COST507) ships in the repository’s database/ folder. For larger databases such as Al–Co–Cr–Fe–Mn–Ni–C, please check out publications in CALPHAD journal.

Example

import equilipy as eq

DB = eq.read_dat("database/AlCuMgSi_ORNL_FS83.dat")

NPT = {"T": 700, "P": 1, "Al": 0.06, "Cu": 0.42, "Si": 0.52}
res = eq.equilib_single(DB, NPT)

print(res.stable_phases.names)   # stable phase names
print(res.G, res.H, res.S)       # system properties, J and J/K

More runnable scripts are in the repository’s example folder:

python example/Example01_SingleEquilib.py

Continue with Python scripting for batch calculations, solidification, and results handling, or GUI for the desktop application.

Note

Examples use the Polars dataframe library and its fastexcel Excel reader, both installed by default. On old CPUs use pip install polars-lts-cpu.

About the project

License

Equilipy is distributed under a BSD 3-Clause License.

Code of Conduct

We as contributors and maintainers pledge to make participation in our project and community a positive experience for everyone.

View our Code of Conduct on our GitHub repository.