TCNI13 Elements, Systems, and Phases
This section summarizes the available elements, assessed systems, and total number of phases in the TCS Ni-based Superalloys Database (TCNI).
Included Elements
There are 31 elements included in the most recent version of the database.
| Included Elements | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Al | Ar* | B | C | Ca | Co | Cr | Cu | Fe | H* |
| Hf | Mg | Mn | Mo | N | Nb | Ni | O | P | Pd |
| Pt | Re | Ru | S | Si | Ta | Ti | V | W | Y |
| Zr | |||||||||
| * Ar and H are only included in the gas phase. | |||||||||
Assessed Systems and Phases
The most recent version of the database contains:
- 371 assessed binary systems, which can be calculated with the BINARY module in Thermo‑Calc Console Mode.
- 433 assessed ternary systems mostly to their full range of composition at least those being in equilibrium with γ and γ’ phase. These can be calculated with the TERNARY module in Thermo‑Calc Console Mode.
- 732 solution and intermetallic phases, where nearly all stable phases in all assessed binary systems and most ternary systems are modeled.
About the Phases
In Console Mode, you can list phases and constituents in the Database (TDB) module and the Gibbs (GES) module. For some phases, supplementary information is included in the definitions. To show the information, it is recommended in the Database (TDB) module to use the command List_System with the option Constituents.
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The database contains an extensive GAS mixture phase for the main purpose of considering oxygen/nitrogen-gas controls in alloy making processes, and different gas atmospheres under, for example, heat treatments.
Argon (Ar) and hydrogen (H) are included in the gas phase only, and there is no solid solubility or condensed phase compounds with these elements included in the database.
- Ordered and disordered BCC (A2 and B2/β) and FCC (A1 and L12/γ´) phases are modeled with a two sub-lattice model using a single Gibbs energy curve which enables order/disorder transformations to be modeled [2001Dup].
- The sigma (σ) and mu (μ) phases—two important Topologically Close-Packed (TCP) phases—are modeled using the Effective Bond Energy Formalism (EBEF) [2018Dup]. This implementation is supported by new Density Functional Theory (DFT) data and employs a five-sublattice (5-SL) model for both phases. The use of EBEF, supported by DFT calculations, results in more physically meaningful thermodynamic descriptions of the σ and μ phases. Moreover, because only effective bond energies of the pairs involved in their configuration are required to fully describe these phases, EBEF enables the use of the 5-SL model [2018Dup; 2024San], which better reflects the actual crystallography of the σ and μ structures. Altogether, this approach enhances the modeling of these phases in binary and ternary systems, as well as across the multicomponent composition space.
- Only the phases of interest for superalloys are defined by default, which means that when retrieving the data from the database other phases will automatically be rejected and would need to be manually restored if these are required for a calculation.
There are several possible composition sets for the phases named FCC_L12 and BCC_B2; they are either disordered (A1/carbonitride and A2) or ordered (L12 (γ’) and B2 (β)).
TCNI13 Models for the Included Phases has detailed descriptions of all phases, e.g. number of sub lattices and elements on each sub lattice and if available also structure, Pearson symbol and Structur Bericht.
Also see Common Phases for the TCNI Database, which lists common phase names and the corresponding Thermo‑Calc database phase names for some key superalloys.
References
[2001Dup] N. Dupin, B. Sundman, A thermodynamic database for Ni‐base superalloys. Scand. J. Metall. 30, 184–192 (2001).
[2001Hil] M. Hillert, The compound energy formalism (1). J. Alloys Compd. 320, 161–176 (2001).
[2018Dup] N. Dupin, U. R. Kattner, B. Sundman, M. Palumbo, S. G. Fries, Implementation of an Effective Bond Energy Formalism in the Multicomponent Calphad Approach. J. Res. Natl. Inst. Stand. Technol. 123, 123020 (2018).
[2024San] J. C. P. dos Santos, S. Griesemer, N. Dupin, U. R. Kattner, C. Liu, D. Ivanova, T. Hammerschmidt, S. G. Fries, C. Wolverton, C. E. Campbell, Applying the Effective Bond Energy Formalism (EBEF) to Describe the Sigma (σ) Phase in the Co-Cr-Ni-Re System. J. Phase Equilibria Diffus. 45, 330–357 (2024).