Questions tagged [calphad]
For questions concerning CALPHAD (CALculation of PHAse Diagrams), a methodology introduced in the 1960s by Larry Kaufman.
10
questions
6
votes
1answer
34 views
Thermo-Calc: how to suspend specific composition sets?
I am attempting to calculate the driving force of nucleation for several different precipitate phases using TC-Python. To this I want to suspend all phases, except for the matrix phase (e.g. FCC_L12). ...
10
votes
1answer
58 views
Pycalphad most efficient way to gather equilibirum phase data for set of alloy compositions?
What's the most efficient way to get the equilibrium phases and phase fractions for a set of alloy compositions? For context, I'm coming from Thermo-Calc/TC-Python where I would just loop through the ...
6
votes
1answer
134 views
Pycalphad “Failed while parsing” Yttrium from light alloys database
The code in question is just 2 lines used to import the "COST507 database for light alloys" (downloaded from the opencalphad homepage http://www.opencalphad.com/).
...
6
votes
1answer
52 views
Is it possible to analytically solve for a particular phase region of a CALPHAD database? (instead of guessing and checking)
As I understand it, a given CALPHAD database is essentially just a set of equations that model the Gibbs free energy of each phase within a given alloy system (set of elements). Typically, the main ...
5
votes
1answer
44 views
Thermo-calc: Calculate precipitation driving force by parallel tangent construction
I want to calculate the difference in Gibbs free energies between a
Zr-Cu-Al liquid (composition - Zr 65 Cu 27.5 Al 7.5 at%) and the CuZr2
solid phase as a function of temperature (300 - 1000 K). In ...
6
votes
1answer
89 views
What information about a crystalline solid material goes into calculating phase diagrams in Thermo-Calc, and how?
Gibbs free energy, $G$, for a crystalline solid material could be described as:
\begin{equation}
G\: =\: H_{T=0}\: +\: H_{T>0}\: +\: \text{ZPE}\: -\: T\cdot S,
\end{equation}
Where $H$ is enthalpy, ...
11
votes
1answer
121 views
How to get order constitution data for single equilibrium calculation in Thermo-Calc's TC Python module?
I know that it is possible to get order constitution data for phases when using Thermo-Calc's GUI (e.g. to get "BCC_B2 DISORD" instead of just "BCC_B2") for a single equilibrium ...
6
votes
0answers
72 views
Why does Thermo-Calc one axis equilibrium calculation get stuck in never ending loop? [closed]
I've been trying to run a Thermo-Calc one axis equilibrium calculation on some quaternary alloys in the TCHEA4 database. Most of the calculations work fine, but for some alloys it gets stuck in a loop ...
8
votes
1answer
97 views
For a Thermo-Calc database, is it possible to view the equation/parameters of the Gibbs free energy models?
I want to get the equations that model free energy for a given phase in a given alloy system (see attached image). I do not just want to get values of free energy for specific compositions. Is it ...
14
votes
3answers
108 views
What thermodynamic data is collected in order to build a CALPHAD model?
To build a model using the CALPHAD approach, i.e. Gibbs free energy as a function of composition and temperature, typically taking the form of a Redlich-Kister polynomial, what kind of thermodynamic ...
