The Calphad module is a thermodynamic calculation module based on Open Calphad developed by Professor Bo Sundman. (Professor Bo Sundman, the originator of Thermo-Calc, a commercial thermodynamic calculation software, developed Open-Calcphad, which makes it possible to use Thermo-Calc freely in Linux.)
Using this module, you can calculate the kind of the phase in a microstructure of alloys due to the heat-treatment temperature, the amount of the phase, the component in the phase, heat-treatment information for the microstructure, etc.

The Calphad module gives five services.

  • You can calculate the information of each phase according to the temperature condition.
  • You can calculate the phase diagram between two elements.
  • You can calculate the phase diagram between three elements.
  • You can calculate each phase information of the microstructure of alloy with various elements added according to the temperature.
  • You can calculate energy function (G, H, S, activity, etc) according to the temperature or composition. If you want to know the types of function information you can get, please refer to the Calphad Function Diagram section.
  • You can calculate the phase information of alloy according to the custom settings.



To perform better thermodynamic calculation, the most importance is the thermodynamic database.
It is important how well the multi-component database describes binary and ternary information. Generally, if the database describe well the binary and ternary information, can expand to multi-component. Therefore, user must check the binary and ternary information of the database, and use the database suitably.
We trying to offer a better database. Please keep in the mind differing the calculation cost to obtain the phase diagram result according to the quality of the database.



We will provide a more high-quality and improved database soon.



This database is the database by COST 507 project which carried out to obtain the thermodynamic information of Light metal alloy (Al-base, Mg-base, Ti-Al-base) in the 90s.


Al, B, C, Ce, Cr, Cu, Fe, Li, Mg, Mn, N, Nd, Ni, Si, Sn, Ti, Y, Zn, Zr




None


  • Al-base alloys (Al content is 95wt.% or more)
  • Mg-base alloys (Mg content is 95wt.% or more)
  • Ti-Al based alloys (Sum of other alloy elements content is 5wt.% or less)



This database is a test database created from the SSOL2 database.

When using this database, It is recommended using the following alloy elements range. (mass percent)
Fe > 50 | Cr < 30 | Mo < 10 | Si < 5 | V < 5 | C < 2




  • C-Cr-Fe
  • C-Cr-V
  • C-Fe-Si
  • C-Fe-V
  • C-Fe-Mo
  • Cr-Fe-V




This database is a test database created from the SSOL2 database.

When using this database, It is recommended using the following alloy elements range. (mass percent)
Fe > 50 | Cr < 30 | Mn < 15 | Mo < 5 | Ni < 20 | N < 1




  • Cr-Fe-Mn
  • Cr-Fe-N
  • Cr-Fe-N
  • Cr-Fe-Ni
  • Cr-Mo-N
  • Cr-N-Ni
  • Fe-Mo-Ni
  • Fe-Mo-N
  • Fe-N-Ni




This is the database about Solder alloy.


Ag, Bi, Cu, Pb, Sb, Sn




  • Ag-Cu-Pb
  • Ag-Cu-Sn
  • Ag-Pb-Sn
  • Ag-Sb-Sn
  • Bi-Pb-Sn




This database is a commercial database developed by professor Byeong-Joo, Lee of POSTECH, Korea, who is the global authority of thermodynamics field.
Professor Lee has contributed to developing TCFE series database, one of the best-known steel alloy commercial database, through a decade joint research.
We pride this Fe series commercial database have world-best prediction capability for steel alloy.



Fe > 50 | Al < 5 | Cr < 30 | Mn < 25 | Mo < 5 | Nb < 1
Ni < 20 | Si < 5 | Ti < 1 | V < 5 | C < 2 | N < 1


But in some cases, you can obtain meaningful results even the contents are over the range.



  • Lee, Seok Gyu et al. 2020, “Effects of Cr addition on Charpy impact energy in austenitic 0.45C-24Mn-(0,3,6)Cr steels”, Materials Science and Technology, in press.
  • Jafari, Majid et al. 2020, “Evolution of microstructure and tensile properties of cold-drawn hyper-eutectoid steel wires during post-deformation annealing”, Materials Science and Technology 41: 1-11
  • Choi, Yong Hoon et al. 2019. “Influence of Initial Microstructures on Intercritical Annealing Behaviour in a Medium Mn Steel.” Materials Science and Technology 35(17): 2092–2100.
  • Song, Hyejin et al. 2018. “Improvement of Tensile Properties in (Austenite+ferrite+κ-Carbide) Triplex Hot-Rolled Lightweight Steels.” Materials Science and Engineering: A 730: 177–86.
  • Jung, Seungmun et al. 2017. “Effects of Mn and Mo Addition on High-Temperature Tensile Properties in High-Ni-Containing Austenitic Cast Steels Used for Turbo-Charger Application.” Materials Science and Engineering: A 682: 147–55.
  • Kim, Hyunmin et al. 2015. “Dynamic Tension–Compression Asymmetry of Martensitic Transformation in Austenitic Fe–(0.4,1.0)C–18Mn Steels for Cryogenic Applications.” Acta Materialia 96: 37–46.
  • Sohn, Seok Su, Byeong-Joo Lee, Sunghak Lee, and Jai-Hyun Kwak. 2014. “Effect of Mn Addition on Microstructural Modification and Cracking Behavior of Ferritic Light-Weight Steels.” Metallurgical and Materials Transactions A 45(12): 5469–85.
  • Sohn, S S, B.-J. Lee, S Lee, and J.-H. Kwak. 2013. “Effects of Aluminum Content on Cracking Phenomenon Occurring during Cold Rolling of Three Ferrite-Based Lightweight Steel.” Acta Materialia 61(15): 5626–35.




This database is the commercial database of high-entropy alloy developed by research team of professor Lee of POSTECH, Korea, the global authority of thermodynamics field.
The database is that added V to Cantor system (Co-Cr-Ni-Fe-Mn), We pride it has world-best prediction capability for the HEA.






  • Co-Cr-Ni
  • Co-Cr-Fe
  • Co-Cr-Mn
  • Co-Ni-Fe
  • Co-Ni-Mn
  • Co-Fe-Mn
  • Cr-Ni-Fe
  • Cr-Fe-Mn
  • Cr-Ni-Mn
  • Ni-Fe-Mn



  • Yang, Junha et al, “Effects of transformation-induced plasticity (TRIP) on tensile property improvement of Fe45Co30Cr10V10Ni5-xMnx high-entropy alloys”, Mater. Sci. Eng. A 772,138809 (2020.01).
  • Jo, Yong Hee et al. “Cryogenic-temperature fracture toughness analysis of non-equi-atomic V10Cr10Fe45Co20Ni15 high-entropy alloy” J. Alloys and Compds. 809, 151864 (2019.11) .
  • Wei, Daixiu et al. “Novel Co-rich high performance twinning-induced plasticity (TWIP) and transformation-induced plasticity (TRIP) high-entropy alloys”, Scripta Mater. 165, 39-43 (2019.05).
  • Ondichoe, Ibrahim et al. “Experimental investigation and phase diagram of CoCrMnNi-Fe system bridging high-entropy alloys and high-alloyed steels” J. Alloys and Compds. 785, 320-327 (2019.05).
  • Bae, Jae Wung et al. “Effect of mu-precipitates on the microstructure and mechanical properties of non-equiatomic CoCrFeNiMo medium-entropy alloys” J. Alloys and Compds. 781, 75-83 (2019.04).
  • Jo, Yong Hee et al. “FCC to BCC transformation-induced plasticity based on thermodynamic phase stability in novel V10Cr10Fe45CoxNi35-x medium-entropy alloys” Sci. Rep. 9, 2948 (2019.02).




Some examples of what data can obtain by Calphad User-defined menu.


This example is useful when you want to know the state of each phase by temperature according to the amount of one element in a situation where different amounts of alloying elements are determined.
We will obtain the phase information by temperature according to the amount of Cr when 8wt.% Ni.


Select Fe, Cr, Ni
Select Steel database
Select All phase
Setting initial parameters
Major Element: Fe
Cr = 0.5, Ni = 0.08
Temp. = 1200 K
Mol/Weight: Weight


Select axis
For Axis 1, Type is fraction, Min = 0, Max = 0.9, increment = 0.01, Element = Cr
For Axis 2, Type is Temp., Min = 600, Max = 2000, increment = 10


Put Job name and click Start Job button

The result is:
If you want to know the phase at 25 wt.%, 750 K, write that conditions as an initial parameter at the [List-equilibrium] tab. Getting the phase information of that condition by real list-equilibrium graph, we can find out the Fe-rich bcc phase exists 75.6%, Cr-rich bcc phase exists 11.8%, Fcc phase 10.9% exists.



This example is want to find out the solubility line of VC carbide in austenite at the 10Mo-4.5Cr-0.1Si HS steel when the temperature is 1300 K.

Select Fe, Cr, Mo, Si, V, C
Select Steel database
Select FCC_A1 only
Setting initial parameters
Major Element: Fe
Cr = 0.045, Mo = 0.1, Si = 0.001, V = 0.009, C = 0.009
Temp. = 1300 K
Mol/Weight: Weight


Select axis
For Axis 1, Type is fraction, Min = 0, Max = 0.015, increment = 0.0005, Element = V
For Axis 2, Type is fraction, Min = 0, Max = 0.01, increment = 0.0005, Element = C


Put the Job name and click Start Job button.

The result is:

This result can analyze like the following figure by [List-equilibrium] tab.

We can check the crystallization amout of VC carbide exists in the Austenite according to how much the amount of V and C at the final.






Type Description Unit
G Total gibbs energy for the system J
H Total enthalpy for the system J
S Total entropy for the system J/K
CP Heat capacity for the system J/K
GM(*) The gibbs energy of individual phases J/mol
HM(*) The enthalpy of individual phases J/mol
SM(*) The entropy of individual phases J/mol
G(*) The gibbs energy of individual phases J
H(*) The enthalpy of individual phases J
S(*) The entropy of individual phases J
AC(*) The activity of individual elements
Function Custom mode


This mode is used when you want to know the change of energy as the function of a specific phase or element.


  • GM(FCC)
  • GM(FCC)-GM(BCC)
  • HM(FCC)-HM(BCC)
  • SM(FCC)-SM(HCP)
  • GM(FCC)-HM(FCC)
  • GM(FCC)-HM(BCC)
  • AC(Ni)

In this way, functions can also be computed each other.



This page has been created by SimPL. Last update: Jul 02, 2020