Fe–Tb phases

8 phases (tier A 5, tier C 2, liquid 1); 8 stable in a calculated diagram. Structure types are assigned only when the stored evidence supports an assignment under the stated tier rules (tier A: standard phase name; tier B: unique Materials Project + OQMD on-hull match, DFT-supported; tier C: one structure stated by the assessment's crystallographic table, assessor-stated); other phases list candidates and are marked needs_review. Stability is from phase diagrams calculated with pycalphad from the SGTE binary collection (evidence class: model).

Data: interactive registry · full JSON · Fe–Tb system page · Markdown · field reference

Phases of the Fe–Tb system (8)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BCC_A2 phase:fe-tb:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 3 of 3 calculated diagram(s): 300–2499.63 K, x(Tb) 0–1	0	3
FCC_A1 phase:fe-tb:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 3 of 3 calculated diagram(s): 1169.93–1742.36 K, x(Tb) 0–0.0028	0	3
FE17TB2 phase:fe-tb:fe17tb2	Ni17Th2 · hP38 · P6_3/mmc (194)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 3 of 3 calculated diagram(s): 300–1587.21 K, x(Tb) 0.10526–0.10526	21	3
FE23TB6_D8A phase:fe-tb:fe23tb6-d8a	Mn23Th6 · D8_a · cF116 · Fm-3m (225)	tier A: standard phase name	stable in 3 of 3 calculated diagram(s): 300–1561 K, x(Tb) 0.2069–0.2069	0	3
FE2TB_C15 phase:fe-tb:fe2tb-c15	Cu2Mg · C15 · cF24 · Fd-3m (227)	tier A: standard phase name	stable in 3 of 3 calculated diagram(s): 300–1461.48 K, x(Tb) 0.33333–0.33333	0	3
FE3TB phase:fe-tb:fe3tb	Ni3Pu · hR12 · R-3m (166)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 3 of 3 calculated diagram(s): 300–1485.39 K, x(Tb) 0.25–0.25	11	3
HCP_A3 phase:fe-tb:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	stable in 3 of 3 calculated diagram(s): 300–1627 K, x(Tb) 0.99798–1	0	3
LIQUID phase:fe-tb:liquid	liquid	liquid	stable in 3 of 3 calculated diagram(s): 1116.04–2500 K, x(Tb) 0–1	6	3

BCC_A2 (Fe–Tb)

Id: phase:fe-tb:bcc-a2; status assigned
Structure: W · A2 · cI2 · Im-3m (229); type st:a2-w-ci2; tier A: standard phase name; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 300–2499.63 K, x(Tb) 0–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:fe-tb:bcc-a2
tdb: tdb:FeTb-17Ron.tdb:BCC_A2, tdb:FeTb-23Ye.tdb:BCC_A2, tdb:FeTb-94Lan.tdb:BCC_A2

TDB models of BCC_A2 (3): PHASE and CONSTITUENT statements as written

FeTb-17Ron.tdb: BCC_A2, type code %B, sha256 46346f5bff319295…

34: PHASE BCC_A2 %B 2 1 3 !
35: CONST BCC_A2 : FE TB : VA : !

FeTb-23Ye.tdb: BCC_A2, type code %B, sha256 0eb2e62ea5c9bc11…

36: PHASE BCC_A2 %B 2 1 3 !
37: CONST BCC_A2 : FE TB : VA : !

FeTb-94Lan.tdb: BCC_A2, type code %B, sha256 4276274a275273a7…

35: PHASE BCC_A2 %B 2 1 3 !
36: CONST BCC_A2 : FE TB : VA : !

Example references (2 of 2; assessments first):

doi:10.1016/0925-8388(94)90261-5 S. Landin, J. Agren, J. Alloys Compd., 207-208, 449-53(1994).
assessment that models this phase
doi:10.1016/j.calphad.2017.10.003 M.H. Rong, X.L. Chen, J. Wang, G.H. Rao, H.Y. Zhou, Calphad, 59, 154-63(2017).
assessment that models this phase

FCC_A1 (Fe–Tb)

Id: phase:fe-tb:fcc-a1; status assigned
Structure: Cu · A1 · cF4 · Fm-3m (225); type st:a1-cu-cf4; tier A: standard phase name; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 1169.93–1742.36 K, x(Tb) 0–0.0028
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:fe-tb:fcc-a1
tdb: tdb:FeTb-17Ron.tdb:FCC_A1, tdb:FeTb-23Ye.tdb:FCC_A1, tdb:FeTb-94Lan.tdb:FCC_A1

TDB models of FCC_A1 (3): PHASE and CONSTITUENT statements as written

FeTb-17Ron.tdb: FCC_A1, type code %A, sha256 46346f5bff319295…

29: PHASE FCC_A1 %A 2 1 1 !
30: CONST FCC_A1 : FE% TB : VA : !

FeTb-23Ye.tdb: FCC_A1, type code %A, sha256 0eb2e62ea5c9bc11…

31: PHASE FCC_A1 %A 2 1 1 !
32: CONST FCC_A1 : FE% TB : VA : !

FeTb-94Lan.tdb: FCC_A1, type code %A, sha256 4276274a275273a7…

30: PHASE FCC_A1 %A 2 1 1 !
31: CONST FCC_A1 : FE% TB : VA : !

Example references (2 of 2; assessments first):

doi:10.1016/0925-8388(94)90261-5 S. Landin, J. Agren, J. Alloys Compd., 207-208, 449-53(1994).
assessment that models this phase
doi:10.1016/j.calphad.2017.10.003 M.H. Rong, X.L. Chen, J. Wang, G.H. Rao, H.Y. Zhou, Calphad, 59, 154-63(2017).
assessment that models this phase

FE17TB2 (Fe–Tb)

Id: phase:fe-tb:fe17tb2; status assigned
Structure: Ni17Th2 · hP38 · P6_3/mmc (194); type st:ni17th2-hp38; tier C: assessor-stated (Hallstedt 2025 crystallographic table); confidence assessor-stated
Structure source: B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, supplementary crystallographic table (mmc2) doi:10.1016/j.calphad.2025.102833
Caveat: not certain from the name or DFT alone (no_on_hull_entry_in_both, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: Fe 0.8947, Tb 0.1053
Stability: stable in 3 of 3 calculated diagram(s): 300–1587.21 K, x(Tb) 0.10526–0.10526
Literature: 21 values (21 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:fe-tb:fe17tb2
paper: paper:10.20517/jmi.2023.08:Fe17Tb2
tdb: tdb:FeTb-17Ron.tdb:FE17TB2, tdb:FeTb-23Ye.tdb:FE17TB2, tdb:FeTb-94Lan.tdb:FE17TB2

TDB models of FE17TB2 (3): PHASE and CONSTITUENT statements as written

FeTb-17Ron.tdb: FE17TB2, type code %, sha256 46346f5bff319295…

44: PHASE FE17TB2 % 2 17 2 !
45: CONST FE17TB2 : FE : TB : !

FeTb-23Ye.tdb: FE17TB2, type code %, sha256 0eb2e62ea5c9bc11…

46: PHASE FE17TB2 % 2 17 2 !
47: CONST FE17TB2 : FE : TB : !

FeTb-94Lan.tdb: FE17TB2, type code %, sha256 4276274a275273a7…

45: PHASE FE17TB2 % 2 17 2 !
46: CONST FE17TB2 : FE : TB : !

Example references (3 of 3; assessments first):

doi:10.1016/0925-8388(94)90261-5 S. Landin, J. Agren, J. Alloys Compd., 207-208, 449-53(1994).
assessment that models this phase
doi:10.1016/j.calphad.2017.10.003 M.H. Rong, X.L. Chen, J. Wang, G.H. Rao, H.Y. Zhou, Calphad, 59, 154-63(2017).
assessment that models this phase
doi:10.20517/jmi.2023.08 Hongjian Ye, Maohua Rong, Qing Chen, Qingrong Yao, Jiang Wang, Guanghui Rao et al., Assessment of phase equilibria and thermodynamic properties in the Fe-RE (RE = rare earth metals) binary systems, J Mater Inf 3 (2023).
reports values for this phase

FE23TB6_D8A (Fe–Tb)

Id: phase:fe-tb:fe23tb6-d8a; status assigned
Structure: Mn23Th6 · D8_a · cF116 · Fm-3m (225); type st:d8-a-mn23th6-cf116; tier A: standard phase name; confidence high
Stoichiometry: Fe 0.7931, Tb 0.2069
Stability: stable in 3 of 3 calculated diagram(s): 300–1561 K, x(Tb) 0.2069–0.2069
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:fe-tb:fe23tb6-d8a
tdb: tdb:FeTb-17Ron.tdb:FE23TB6_D8A, tdb:FeTb-23Ye.tdb:FE23TB6_D8A, tdb:FeTb-94Lan.tdb:FE23TB6_D8A

TDB models of FE23TB6_D8A (3): PHASE and CONSTITUENT statements as written

FeTb-17Ron.tdb: FE23TB6_D8A, type code %, sha256 46346f5bff319295…

49: PHASE FE23TB6_D8A % 2 23 6 !
50: CONST FE23TB6_D8A : FE : TB : !

FeTb-23Ye.tdb: FE23TB6_D8A, type code %, sha256 0eb2e62ea5c9bc11…

51: PHASE FE23TB6_D8A % 2 23 6 !
52: CONST FE23TB6_D8A : FE : TB : !

FeTb-94Lan.tdb: FE23TB6_D8A, type code %, sha256 4276274a275273a7…

50: PHASE FE23TB6_D8A % 2 23 6 !
51: CONST FE23TB6_D8A : FE : TB : !

Example references (2 of 2; assessments first):

doi:10.1016/0925-8388(94)90261-5 S. Landin, J. Agren, J. Alloys Compd., 207-208, 449-53(1994).
assessment that models this phase
doi:10.1016/j.calphad.2017.10.003 M.H. Rong, X.L. Chen, J. Wang, G.H. Rao, H.Y. Zhou, Calphad, 59, 154-63(2017).
assessment that models this phase

FE2TB_C15 (Fe–Tb)

Id: phase:fe-tb:fe2tb-c15; status assigned
Structure: Cu2Mg · C15 · cF24 · Fd-3m (227); type st:c15-cu2mg-cf24; tier A: standard phase name; confidence high
Stoichiometry: Fe 0.6667, Tb 0.3333
Stability: stable in 3 of 3 calculated diagram(s): 300–1461.48 K, x(Tb) 0.33333–0.33333
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:fe-tb:fe2tb-c15
tdb: tdb:FeTb-17Ron.tdb:FE2TB_C15, tdb:FeTb-23Ye.tdb:FE2TB_C15, tdb:FeTb-94Lan.tdb:FE2TB_C15

TDB models of FE2TB_C15 (3): PHASE and CONSTITUENT statements as written

FeTb-17Ron.tdb: FE2TB_C15, type code %, sha256 46346f5bff319295…

59: PHASE FE2TB_C15 % 2 2 1 !
60: CONST FE2TB_C15 : FE : TB : !

FeTb-23Ye.tdb: FE2TB_C15, type code %, sha256 0eb2e62ea5c9bc11…

61: PHASE FE2TB_C15 % 2 2 1 !
62: CONST FE2TB_C15 : FE : TB : !

FeTb-94Lan.tdb: FE2TB_C15, type code %, sha256 4276274a275273a7…

60: PHASE FE2TB_C15 % 2 2 1 !
61: CONST FE2TB_C15 : FE : TB : !

Example references (2 of 2; assessments first):

doi:10.1016/0925-8388(94)90261-5 S. Landin, J. Agren, J. Alloys Compd., 207-208, 449-53(1994).
assessment that models this phase
doi:10.1016/j.calphad.2017.10.003 M.H. Rong, X.L. Chen, J. Wang, G.H. Rao, H.Y. Zhou, Calphad, 59, 154-63(2017).
assessment that models this phase

FE3TB (Fe–Tb)

Id: phase:fe-tb:fe3tb; status assigned
Structure: Ni3Pu · hR12 · R-3m (166); type st:ni3pu-hr12; tier C: assessor-stated (Hallstedt 2025 crystallographic table); confidence assessor-stated
Structure source: B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, supplementary crystallographic table (mmc2) doi:10.1016/j.calphad.2025.102833
Caveat: not certain from the name or DFT alone (no_on_hull_entry_in_oqmd, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: Fe 0.7500, Tb 0.2500
Stability: stable in 3 of 3 calculated diagram(s): 300–1485.39 K, x(Tb) 0.25–0.25
Literature: 11 values (11 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:fe-tb:fe3tb
paper: paper:10.20517/jmi.2023.08:Fe3Tb
tdb: tdb:FeTb-17Ron.tdb:FE3TB, tdb:FeTb-23Ye.tdb:FE3TB, tdb:FeTb-94Lan.tdb:FE3TB

TDB models of FE3TB (3): PHASE and CONSTITUENT statements as written

FeTb-17Ron.tdb: FE3TB, type code %, sha256 46346f5bff319295…

54: PHASE FE3TB % 2 3 1 !
55: CONST FE3TB : FE : TB : !

FeTb-23Ye.tdb: FE3TB, type code %, sha256 0eb2e62ea5c9bc11…

56: PHASE FE3TB % 2 3 1 !
57: CONST FE3TB : FE : TB : !

FeTb-94Lan.tdb: FE3TB, type code %, sha256 4276274a275273a7…

55: PHASE FE3TB % 2 3 1 !
56: CONST FE3TB : FE : TB : !

Example references (3 of 3; assessments first):

doi:10.1016/0925-8388(94)90261-5 S. Landin, J. Agren, J. Alloys Compd., 207-208, 449-53(1994).
assessment that models this phase
doi:10.1016/j.calphad.2017.10.003 M.H. Rong, X.L. Chen, J. Wang, G.H. Rao, H.Y. Zhou, Calphad, 59, 154-63(2017).
assessment that models this phase
doi:10.20517/jmi.2023.08 Hongjian Ye, Maohua Rong, Qing Chen, Qingrong Yao, Jiang Wang, Guanghui Rao et al., Assessment of phase equilibria and thermodynamic properties in the Fe-RE (RE = rare earth metals) binary systems, J Mater Inf 3 (2023).
reports values for this phase

HCP_A3 (Fe–Tb)

Id: phase:fe-tb:hcp-a3; status assigned
Structure: Mg · A3 · hP2 · P6_3/mmc (194); type st:a3-mg-hp2; tier A: standard phase name; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 300–1627 K, x(Tb) 0.99798–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:fe-tb:hcp-a3
tdb: tdb:FeTb-17Ron.tdb:HCP_A3, tdb:FeTb-23Ye.tdb:HCP_A3, tdb:FeTb-94Lan.tdb:HCP_A3

TDB models of HCP_A3 (3): PHASE and CONSTITUENT statements as written

FeTb-17Ron.tdb: HCP_A3, type code %, sha256 46346f5bff319295…

39: PHASE HCP_A3 % 2 1 0.5 !
40: CONST HCP_A3 : FE TB% : VA : !

FeTb-23Ye.tdb: HCP_A3, type code %, sha256 0eb2e62ea5c9bc11…

41: PHASE HCP_A3 % 2 1 0.5 !
42: CONST HCP_A3 : FE TB% : VA : !

FeTb-94Lan.tdb: HCP_A3, type code %, sha256 4276274a275273a7…

40: PHASE HCP_A3 % 2 1 0.5 !
41: CONST HCP_A3 : FE TB% : VA : !

Example references (2 of 2; assessments first):

doi:10.1016/0925-8388(94)90261-5 S. Landin, J. Agren, J. Alloys Compd., 207-208, 449-53(1994).
assessment that models this phase
doi:10.1016/j.calphad.2017.10.003 M.H. Rong, X.L. Chen, J. Wang, G.H. Rao, H.Y. Zhou, Calphad, 59, 154-63(2017).
assessment that models this phase

LIQUID (Fe–Tb)

Id: phase:fe-tb:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 1116.04–2500 K, x(Tb) 0–1
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:fe-tb:liquid
paper: paper:10.20517/jmi.2023.08:L
tdb: tdb:FeTb-17Ron.tdb:LIQUID, tdb:FeTb-23Ye.tdb:LIQUID, tdb:FeTb-94Lan.tdb:LIQUID

TDB models of LIQUID (3): PHASE and CONSTITUENT statements as written

FeTb-17Ron.tdb: LIQUID, type code %, sha256 46346f5bff319295…

24: PHASE LIQUID:L % 1 1 !
25: CONST LIQUID:L : FE TB : !

FeTb-23Ye.tdb: LIQUID, type code %, sha256 0eb2e62ea5c9bc11…

26: PHASE LIQUID:L % 1 1 !
27: CONST LIQUID:L : FE TB : !

FeTb-94Lan.tdb: LIQUID, type code %, sha256 4276274a275273a7…

25: PHASE LIQUID:L % 1 1 !
26: CONST LIQUID:L : FE TB : !

Example references (3 of 3; assessments first):

doi:10.1016/0925-8388(94)90261-5 S. Landin, J. Agren, J. Alloys Compd., 207-208, 449-53(1994).
assessment that models this phase
doi:10.1016/j.calphad.2017.10.003 M.H. Rong, X.L. Chen, J. Wang, G.H. Rao, H.Y. Zhou, Calphad, 59, 154-63(2017).
assessment that models this phase
doi:10.20517/jmi.2023.08 Hongjian Ye, Maohua Rong, Qing Chen, Qingrong Yao, Jiang Wang, Guanghui Rao et al., Assessment of phase equilibria and thermodynamic properties in the Fe-RE (RE = rare earth metals) binary systems, J Mater Inf 3 (2023).
reports values for this phase

Please cite

R. Arróyave, J. Saal, D. Shin, ORCHID-Registry: phase registry of binary systems (version 2026.10; Version 1, machine-extracted), Zenodo (2026). doi:10.5281/zenodo.23735970
R. Arróyave, J. Saal, D. Shin, ORCHID data: umbrella record of the ORCHID datasets (version 2026.10; Version 1, machine-extracted), Zenodo (2026). doi:10.5281/zenodo.23736065

Also cite B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, https://doi.org/10.1016/j.calphad.2025.102833 (CC BY 4.0), and the original assessment named in each file; A. Jain et al., The Materials Project: A materials genome approach to accelerating materials innovation, APL Materials 1 (2013) 011002, https://doi.org/10.1063/1.4812323 (CC BY 4.0); J. E. Saal et al., JOM 65 (2013) 1501, https://doi.org/10.1007/s11837-013-0755-4 and S. Kirklin et al., npj Comput. Mater. 1 (2015) 15010, https://doi.org/10.1038/npjcompumats.2015.10 (CC BY 4.0); the original source of every value you use (paper_citation / paper_doi, and cited_dois for values the paper cites from earlier work). Version 1, machine-extracted: values were read by language-model readers constrained to quote their source and checked automatically, and the release was then audited on the printed pages by adversarial audits, an independent second review of fit-facing records and a preliminary human review of a frozen sample. Flags such as accepted and ESPEI-ready record screening results, not certification; known issues are listed in the release notes.

@misc{orchid_phase_registry_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Registry: phase registry of binary systems}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735970},
  url       = {https://doi.org/10.5281/zenodo.23735970},
  note      = {Version 1, machine-extracted}
}

@misc{orchid_data_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID data: umbrella record of the ORCHID datasets}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23736065},
  url       = {https://doi.org/10.5281/zenodo.23736065},
  note      = {Version 1, machine-extracted}
}