Common Phases for Titanium Alloys

The following lists common phase names and the corresponding Thermo‑Calc database phase names for some key titanium alloys.

Electrical resistivity and thermal conductivity are only assessed for the phases listed here except those marked with an asterisk (*).

TCTI6 Models for the Included Phases

Name in the Database	Common Name and Description
ALTI_L10	This is the γ phase in TiAl-based alloys.
ALTI3_D019	This is the α₂ phase.
BCC_B2	This is the β phase. The ordered B2 phase with the disordered BCC_A2 has been modeled with the so-called partition model. It is always labeled as BCC_B2 in calculations with TCTI. It is necessary to check the constitution of the phase to find out whether it is ordered or not. Electrical resistivity and thermal conductivity are assessed for BCC_A2, BCC_B2 with available data.
B19_ORTHO*	This is the orthorhombic martensite in Ti-Ni-based alloys.
B19_PRIME*	This is the monoclinic martensite in Ti-Ni-based alloys.
B82_omega	This is the ω_o phase in TiAl-based alloys.
CUZR2_C11B	CuTi₂ is modeled as this phase.
CU4TI1	Cu₄Ti is modeled as this phase.
DELTA_TIH2	This is the delta dihydride (eg. TiH₂) with CaF₂ as prototype.
FCC_B1	Titanium carbide, nitride, oxide with NaCl as prototype.
HCP_A3	This is the α phase. The descriptions of α' (Hcp martensite) and α" (orthorhombic martensite) are unified into HCP_A3 phase in the database by now.
Liquid	Metallic liquid solution.
MSI_B27	TiSi is modeled as this phase.
M3SI1	Ti₃Si is modeled as this phase.
M5SI3_D88	Ti₅Si₃ is modeled as this phase.
O_PHASE	This is the orthorhombic phase stable in Ti-Al-Nb, Ti-Al-Ta and possibly in multicomponent TiAl alloys.
OMEGA*	The omega phase is a metastable phase which forms in titanium and its alloys with transition elements (like V, Mo, Nb, Fe, etc).
R_MARTE*	This is an intermediate martensite, R-phase, in Ti-Ni-based alloys.
RUTILE_TIO2	TiO₂ is modeled as this phase.
TiB_B27	TiB is modeled as this phase.
TiB2_C32	TiB₂ is modeled as this phase.
Ti2N_C4	Ti₂N is modeled as this phase.
Ti2Ni3*	This is a tetragonal metastable precipitate in Ti-Ni alloys.
Ti3Ni4*	This is a metastable precipitate in Ti-Ni alloys.
Ti3B4	Ti₃B₄ is modeled as this phase.
Ti3N2	η-Ti₃N_2-x phase in Ti-N binary.
Ti4N3	-Ti₄N_3-x phase in Ti-N binary.
TiSi2_C54	TiSi₂ is modeled as this phase.
Zr5Si4	Ti₅Si₄ is modeled as this phase.
* Electrical resistivity and thermal conductivity are not assessed for this phase.