TCTI: TCS Ti/TiAl-based Alloys Database Revision History

Software release version 2025a (January 2025)

Unary Systems

• Reassessed elastic constant model parameters to ensure that the calculated results at high temperatures align more closely with physically expected behavior.
  • FCC_A1: Ni
  • BCC_A2: Fe, Mo, Nb, Ta, Ti, V, W, Zr
  • HCP_A3: Co, Ti, Zr
• Reassessed elastic constant model parameters for metastable systems that enhance model consistency and improve composition profiles for both titanium-containing and non-titanium binary systems.
  • FCC_A1: Co, Cr
  • BCC_A2: Al
  • HCP_A3: Cr, Mo, Nb, V
• Fixed rounding error that affected the calculated accuracy of a few systems.

Binary Systems

Reassessed binary interaction parameters affected by the adjustments made to unary elastic constant model parameters.

• BCC_A2:
  • Ti-X (X = Al, Cr, Mo, Nb, Sn, Ta, V, W, Zr)
  • Mo-X (X = Nb, Sn, Ta, W, Zr)
  • Nb-X (X = Al, Sn, Ta, V, W, Zr)
  • Sn-X (X = Ta, Zr)
  • W-X (X = Cr, Ta, V, Zr)
  • Zr-X (X = Ta, V)
• HCP_A3: Ti-X (X = Al, Cr, Mo, Nb, Sn, V, Zr)

Software release version: 2024b (June 2024)

New Elastic Properties

• New elastic moduli (bulk modulus, shear modulus, and Young’s modulus) available.
• New elastic constants (C11, C12, C13, C33, and C44) available for the metallic elements for BCC, HCP, and FCC phases.

Thermodynamic Assessments

• The description of Ti-Ni system is updated for shape memory alloys. The B19_PRIME, B19_ORTHO, and R_MARTE martensite phases are included in addition to the metastable Ti₂Ni₃, and Ti₃Ni₄ intermetallic phases which play an important role as precipitates in shape memory alloys.
• Related Ti-Ni-X systems are also updated: Ti-Al-Ni, Ti-B-Ni, Ti-Cu-Ni, Ti-H-Ni, Ti-Ni-Pd, and Ti-Ni-Sn.
• Ti-Al-Ta, Ti-Cr-Fe, Mn-W, and O-Sn are improved with more accurate prediction of phase stabilities.
• Full gas descriptions are updated.

Other Improvements

• Improved surface tension of Fe-Ni.
• Molar volumes of BCC_A2 phase are revised for the systems Al-V, Nb-Ti, Ta-Ti, Al-Ti-V, and Ti-V-Zr.

Software release version: 2023b (June 2023)

• The surface tension was re-assessed based on the Redlich-Kister-Muggianu (R-K-M) sub-regular solution model.

Software release version: 2023a (December 2022/January 2023)

• Updates to Ti-Al-B, Ti-Al-C, Ti-Al-Cr, Ti-Al-Mo, Ti-Al-Nb, Ti-Al-O, Ti-Al-Si, Ti-Al-Sn, Ti-Al-W, and Ti-Al-Zr.
• Modeled the Ti-Si-Zr ternary system.
• Full gas descriptions are added.
• There is a change to default settings. From this release, the GAS phase is restored by default when retrieving the data from the database. In order to reject it when it is not required for a calculation, you have to now manually reject it.

The following volume parameters are updated for:

• Liquid in Ti-V and Ti-Al-V
• AlTi3_D019 in Ti-Al-O
• BCC_A2 in Ti-H
• HCP_A3 in Ti-O and Ti-N

Software release version: 2022a (December 2021/January 2022)

• Added data for electrical resistivity and thermal conductivity
• Two new assessed ternary systems: Ti-Al-Ni and Ti-Cu-Ni.
• Updated volume descriptions for α2 and γ phases.
• Updated description of BCC_A2 in Mo-V and Mo-Ti-V.

Software release version: 2021a (December 2020/January 2021)

• Added Copper (Cu), which is a minor-alloying element in titanium alloys.
• Ti-Cu, Cu-Fe, Cu-H, Cu-N, Cu-Nb, Cu-O, Cu-Si, Cu-Sn, Ti-Cu-C, Ti-Cu-Fe, Ti-Cu-H, Ti-Cu-N, Ti-Cu-Nb, Ti-Cu-O, Ti-Cu-Si, and Ti-Cu-Sn are modeled. Now it is possible to perform calculations for titanium alloys within the framework of Ti-Cu-Sn-Nb-Si. Moreover, the reliability can be enhanced by the availability of considering the effects from common impurities: C, Fe, H, N, and O.
• Al-Cu and Ti-Al-Cu are modeled, which is useful for both Ti- and TiAl-based alloys where alloying effects of Cu are of interest.
• Ti-Hf-Ta, Ti-B-Hf, Ti-Hf-Zr, and B-C-Si are modeled. These systems are of particular use for those involved in the development of biomedical materials because it combines cytocompatibility and improves mechanical properties.
• Ti-Al-Cr is updated.
• Viscosity and surface tension of liquid are included with the database as of this release.

Software release version: 2020b (June 2020)

• Improved description of liquid phase for calculations with yttrium.

Software release version: 2019b (June 2019)

• Improved description of liquidus temperature for Ti64 alloy.
• Adjusted phase stability of HCP_A3 and BCC_A2 in some systems.

Software release version: 2019a (December 2018)

• Volume data for most of the phases assessed.
• 4 new elements: Ag, H, Pd, Pt
• 33 new binary systems are assessed: Ti-Ag, Ti-H, Ti-Pd, Ti-Pt, Ag-Pd, Al-Pd, Cr-Pd, Mo-Pd, Ni-Pd, Pd-V, Pd-Zr, Al-H, B-H, C-H, Co-H, Cr-H, Fe-H, Hf-H, Mn-H, Mo-H, N-H, Nb-H, Ni-H, O-H, Re-H, Ru-H, Si-H, Sn-H, Ta-H, V-H, W-H, Y-H, Zr-H. Most of these are H-containing.
• 24 new ternary systems are modeled: Ti-Ag-Pd, Ti-Al-Fe, Ti-Al-H, Ti-Al-Pd, Ti-Al-Y, Ti-B-Si, Ti-C-Si, Ti-Cr-H, Ti-Cr-O, Ti-Cr-Si, Ti-Fe-Mo, Ti-H-Ni, Ti-H-O, Ti-H-Zr, Ti-Mo-O, Ti-Nb-O, Ti-Nb-Si, Ti-Ni-Pd, Ti-O-Si, Ti-O-Ta, Ti-O-V, Ti-O-W, Ti-O-Zr, Ti-Pd-V.