B–Ta phases

13 phases (tier A 7, tier C 3, liquid 1, needs_review 2); 11 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 · B–Ta system page · Markdown · field reference

Phases of the B–Ta system (13)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BETA_RHOMBO_B phase:b-ta:b-beta-rhombo		needs_review	stable in 2 of 2 calculated diagram(s): 300–3361.75 K, x(B) 1–1	9	2
BCC_A2 phase:b-ta:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–3999.99 K, x(B) 0–0.02571	19	2
FCC_A1 phase:b-ta:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	not stable in 2 calculated diagram(s)	0	2
HCP_A3 phase:b-ta:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	not stable in 2 calculated diagram(s)	0	2
LIQUID phase:b-ta:liquid	liquid	liquid	stable in 2 of 2 calculated diagram(s): 2324.96–4000 K, x(B) 0–1	42	2
TA2B_C16 phase:b-ta:ta2b-c16	Al2Cu · C16 · tI12 · I4/mcm (140)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 2206.36–2690.71 K, x(B) 0.27932–0.33333	38	2
TA3B2_D5A phase:b-ta:ta3b2-d5a	Si2U3 · D5_a · tP10 · P4/mbm (127)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–2473.73 K, x(B) 0.4–0.4	20	2
TA3B4_D7B phase:b-ta:ta3b4-d7b	Ta3B4 · D7_b · oI14 · Immm (71)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–3305.36 K, x(B) 0.57143–0.57143	18	2
TA5B6 phase:b-ta:ta5b6	V5B6 · oC22 · Cmmm (65)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 300–2848.48 K, x(B) 0.54545–0.54545	1	1
TAB phase:b-ta:tab		needs_review	stable in 1 of 1 calculated diagram(s): 300–3357.92 K, x(B) 0.5–0.5	12	1
TAB_B27 phase:b-ta:tab-b27	FeB · B27 · oP8 · Pnma (62)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 3008.42–3358.42 K, x(B) 0.48744–0.49581	6	1
TAB_B33 phase:b-ta:tab-b33	CrB · B33 · oC8 · Cmcm (63)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 300–3168.25 K, x(B) 0.5–0.5	13	1
TAB2_C32 phase:b-ta:tab2-c32	AlB2 · C32 · hP3 · P6/mmm (191)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–3309.05 K, x(B) 0.66634–0.74398	18	2

BETA_RHOMBO_B (B–Ta)

Id: phase:b-ta:b-beta-rhombo; status needs_review
No structure assigned. Why: name_has_descriptive_tokens:RHOMBO; no_structure_token
Candidate (sgte_mmc2): beta-B · hR105 · R-3m (166) — Hallstedt 2025 mmc2 row for BETA_RHOMBO_B: beta-B
Candidate (tdb_comment): beta-B · hR105 · R-3m — TaB-17OuY.tdb: 'Prototype beta-B (hR105, R-3m)'
Candidate (tdb_comment): beta-B · hR105 · R-3m — TaB-18DaS.tdb: 'Prototype beta-B (hR105, R-3m)'
Stoichiometry: B 1.0000
Stability: stable in 2 of 2 calculated diagram(s): 300–3361.75 K, x(B) 1–1
Literature: 9 values (9 accepted) from 2 papers
Interactive: phase registry entry

Names (6): corpus: corpus:phase:b-ta:b-beta-rhombo, corpus:phase:b-ta:beta-rhombo-b
paper: paper:10.1007/s11669-017-0603-2:(B), paper:10.1016/j.calphad.2018.08.012:(βB)
tdb: tdb:TaB-17OuY.tdb:BETA_RHOMBO_B, tdb:TaB-18DaS.tdb:BETA_RHOMBO_B

TDB models of BETA_RHOMBO_B (2): PHASE and CONSTITUENT statements as written

TaB-17OuY.tdb: BETA_RHOMBO_B, type code %, sha256 aaf8efce793d8609…

44: PHASE BETA_RHOMBO_B % 2 93 12 !
45: CONST BETA_RHOMBO_B : B : B : !

TaB-18DaS.tdb: BETA_RHOMBO_B, type code %, sha256 38b9b30e669c48fb…

41: PHASE BETA_RHOMBO_B % 2 93 12 !
42: CONST BETA_RHOMBO_B : B : B : !

Example references (6 of 6; assessments first):

doi:10.1016/j.calphad.2018.08.012 Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-017-0603-2 Xuemei OuYang, Fucheng Yin, Jingxian Hu, Ye Liu, Zhaohui Long, Thermodynamic Modeling of B-Ta and B-C-Ta Systems, J. Phase Equilib. Diffus. 38, 874-886 (2017).
assessment that models this phase; reports values for this phase
doi:10.1007/bf02668242 H. Okamoto, Comment on B-Ta (boron-tantalum), JPE 14, 393-394 (1993).
cited as the source of values for this phase
doi:10.1016/0364-5916(91)90004-4 Lany Kaufman, Coupled thermochemical and phase diagram data for tantalum based binary alloys, Calphad 15, 243-259 (1991).
cited as the source of values for this phase
doi:10.1016/j.jallcom.2015.01.144 Xiaozheng Zhang, Erjun Zhao, Zhijian Wu, Prediction of new high pressure phase of TaB3: First-principles, Journal of Alloys and Compounds 632, 37-43 (2015).
cited as the source of values for this phase
doi:10.1149/1.2428137 James M. Leitnaker, Melvin G. Bowman, Paul W. Gilles, High-Temperature Phase Studies in the Tantalum-Boron System between Ta and TaB, J. Electrochem. Soc. 108, 568 (1961).
cited as the source of values for this phase

BCC_A2 (B–Ta)

Id: phase:b-ta: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 2 of 2 calculated diagram(s): 300–3999.99 K, x(B) 0–0.02571
Literature: 19 values (18 accepted) from 2 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:b-ta:bcc-a2
paper: paper:10.1007/s11669-017-0603-2:(Ta), paper:10.1016/j.calphad.2018.08.012:BCC
tdb: tdb:TaB-17OuY.tdb:BCC_A2, tdb:TaB-18DaS.tdb:BCC_A2

TDB models of BCC_A2 (2): PHASE and CONSTITUENT statements as written

TaB-17OuY.tdb: BCC_A2, type code %B, sha256 aaf8efce793d8609…

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

TaB-18DaS.tdb: BCC_A2, type code %B, sha256 38b9b30e669c48fb…

31: PHASE BCC_A2 %B 2 1 3 !
32: CONST BCC_A2 : TA% : B VA% : !

Example references (6 of 6; assessments first):

doi:10.1016/j.calphad.2018.08.012 Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-017-0603-2 Xuemei OuYang, Fucheng Yin, Jingxian Hu, Ye Liu, Zhaohui Long, Thermodynamic Modeling of B-Ta and B-C-Ta Systems, J. Phase Equilib. Diffus. 38, 874-886 (2017).
assessment that models this phase; reports values for this phase
doi:10.1007/bf02736442 V.M. Chad, É.C.T. Ramos, G.C. Coelho, C.A. Nunes, P.A. Suzuki, F. Ferreira, and P. Rogl, Evaluation of the Invariant 885 Reactions in the Ta-Rich Region of the Ta-B System, J Phase Equilibria Diffus., 2006, 27(5), p 452-455
cited as the source of values for this phase
doi:10.1007/bf02668242 H. Okamoto, Comment on B-Ta (boron-tantalum), JPE 14, 393-394 (1993).
cited as the source of values for this phase
doi:10.1016/0364-5916(91)90004-4 Lany Kaufman, Coupled thermochemical and phase diagram data for tantalum based binary alloys, Calphad 15, 243-259 (1991).
cited as the source of values for this phase
doi:10.1016/j.jallcom.2015.01.144 Xiaozheng Zhang, Erjun Zhao, Zhijian Wu, Prediction of new high pressure phase of TaB3: First-principles, Journal of Alloys and Compounds 632, 37-43 (2015).
cited as the source of values for this phase

FCC_A1 (B–Ta)

Id: phase:b-ta:fcc-a1; status assigned
Structure: Cu · A1 · cF4 · Fm-3m (225); type st:a1-cu-cf4; tier A: standard phase name; confidence high
Stability: not stable in 2 calculated diagram(s)
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:b-ta:fcc-a1
tdb: tdb:TaB-17OuY.tdb:FCC_A1, tdb:TaB-18DaS.tdb:FCC_A1

TDB models of FCC_A1 (2): PHASE and CONSTITUENT statements as written

TaB-17OuY.tdb: FCC_A1, type code %A, sha256 aaf8efce793d8609…

29: PHASE FCC_A1 %A 2 1 1 !
30: CONST FCC_A1 : TA : B VA% : !

TaB-18DaS.tdb: FCC_A1, type code %A, sha256 38b9b30e669c48fb…

26: PHASE FCC_A1 %A 2 1 1 !
27: CONST FCC_A1 : TA : B VA% : !

Example references (2 of 2; assessments first):

doi:10.1007/s11669-017-0603-2 Xuemei OuYang, Fucheng Yin, Jingxian Hu, Ye Liu, Zhaohui Long, Thermodynamic Modeling of B-Ta and B-C-Ta Systems, J. Phase Equilib. Diffus. 38, 874-886 (2017).
assessment that models this phase
doi:10.1016/j.calphad.2018.08.012 Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018).
assessment that models this phase

HCP_A3 (B–Ta)

Id: phase:b-ta: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: not stable in 2 calculated diagram(s)
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:b-ta:hcp-a3
tdb: tdb:TaB-17OuY.tdb:HCP_A3, tdb:TaB-18DaS.tdb:HCP_A3

TDB models of HCP_A3 (2): PHASE and CONSTITUENT statements as written

TaB-17OuY.tdb: HCP_A3, type code %A, sha256 aaf8efce793d8609…

39: PHASE HCP_A3 %A 2 1 0.5 !
40: CONST HCP_A3 : TA : B VA% : !

TaB-18DaS.tdb: HCP_A3, type code %A, sha256 38b9b30e669c48fb…

36: PHASE HCP_A3 %A 2 1 0.5 !
37: CONST HCP_A3 : TA : B VA% : !

Example references (2 of 2; assessments first):

doi:10.1007/s11669-017-0603-2 Xuemei OuYang, Fucheng Yin, Jingxian Hu, Ye Liu, Zhaohui Long, Thermodynamic Modeling of B-Ta and B-C-Ta Systems, J. Phase Equilib. Diffus. 38, 874-886 (2017).
assessment that models this phase
doi:10.1016/j.calphad.2018.08.012 Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018).
assessment that models this phase

LIQUID (B–Ta)

Id: phase:b-ta:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 2 of 2 calculated diagram(s): 2324.96–4000 K, x(B) 0–1
Literature: 42 values (40 accepted) from 2 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:b-ta:liquid
paper: paper:10.1007/s11669-017-0603-2:L, paper:10.1016/j.calphad.2018.08.012:L
tdb: tdb:TaB-17OuY.tdb:LIQUID, tdb:TaB-18DaS.tdb:LIQUID

TDB models of LIQUID (2): PHASE and CONSTITUENT statements as written

TaB-17OuY.tdb: LIQUID, type code %, sha256 aaf8efce793d8609…

24: PHASE LIQUID:L % 1 1 !
25: CONST LIQUID:L : B TA : !

TaB-18DaS.tdb: LIQUID, type code %, sha256 38b9b30e669c48fb…

21: PHASE LIQUID:L % 1 1 !
22: CONST LIQUID:L : B TA : !

Example references (7 of 7; assessments first):

doi:10.1016/j.calphad.2018.08.012 Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-017-0603-2 Xuemei OuYang, Fucheng Yin, Jingxian Hu, Ye Liu, Zhaohui Long, Thermodynamic Modeling of B-Ta and B-C-Ta Systems, J. Phase Equilib. Diffus. 38, 874-886 (2017).
assessment that models this phase; reports values for this phase
doi:10.1007/bf02668242 H. Okamoto, Comment on B-Ta (boron-tantalum), JPE 14, 393-394 (1993).
cited as the source of values for this phase
doi:10.1016/0364-5916(91)90004-4 Lany Kaufman, Coupled thermochemical and phase diagram data for tantalum based binary alloys, Calphad 15, 243-259 (1991).
cited as the source of values for this phase
doi:10.1016/j.jallcom.2015.01.144 Xiaozheng Zhang, Erjun Zhao, Zhijian Wu, Prediction of new high pressure phase of TaB3: First-principles, Journal of Alloys and Compounds 632, 37-43 (2015).
cited as the source of values for this phase
doi:10.1007/bf02736442 V.M. Chad, É.C.T. Ramos, G.C. Coelho, C.A. Nunes, P.A. Suzuki, F. Ferreira, and P. Rogl, Evaluation of the Invariant 885 Reactions in the Ta-Rich Region of the Ta-B System, J Phase Equilibria Diffus., 2006, 27(5), p 452-455
cited as the source of values for this phase
doi:10.1149/1.2428137 James M. Leitnaker, Melvin G. Bowman, Paul W. Gilles, High-Temperature Phase Studies in the Tantalum-Boron System between Ta and TaB, J. Electrochem. Soc. 108, 568 (1961).
cited as the source of values for this phase

TA2B_C16 (B–Ta)

Id: phase:b-ta:ta2b-c16; status assigned
Structure: Al2Cu · C16 · tI12 · I4/mcm (140); type st:c16-al2cu-ti12; tier A: standard phase name; confidence high
Stability: stable in 2 of 2 calculated diagram(s): 2206.36–2690.71 K, x(B) 0.27932–0.33333
Literature: 38 values (36 accepted) from 2 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:b-ta:ta2b-c16
paper: paper:10.1007/s11669-017-0603-2:Ta2B, paper:10.1016/j.calphad.2018.08.012:Ta2B
tdb: tdb:TaB-17OuY.tdb:TA2B_C16, tdb:TaB-18DaS.tdb:TA2B_C16

TDB models of TA2B_C16 (2): PHASE and CONSTITUENT statements as written

TaB-17OuY.tdb: TA2B_C16, type code %, sha256 aaf8efce793d8609…

49: PHASE TA2B_C16 % 2 2 1 !
50: CONST TA2B_C16 : TA : B : !

TaB-18DaS.tdb: TA2B_C16, type code %, sha256 38b9b30e669c48fb…

46: PHASE TA2B_C16 % 2 2 1 !
47: CONST TA2B_C16 : TA : B% VA : !

Example references (6 of 6; assessments first):

doi:10.1016/j.calphad.2018.08.012 Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-017-0603-2 Xuemei OuYang, Fucheng Yin, Jingxian Hu, Ye Liu, Zhaohui Long, Thermodynamic Modeling of B-Ta and B-C-Ta Systems, J. Phase Equilib. Diffus. 38, 874-886 (2017).
assessment that models this phase; reports values for this phase
doi:10.1016/j.jallcom.2015.01.144 Xiaozheng Zhang, Erjun Zhao, Zhijian Wu, Prediction of new high pressure phase of TaB3: First-principles, Journal of Alloys and Compounds 632, 37-43 (2015).
cited as the source of values for this phase
doi:10.1007/bf02668242 H. Okamoto, Comment on B-Ta (boron-tantalum), JPE 14, 393-394 (1993).
cited as the source of values for this phase
doi:10.1007/bf02736442 V.M. Chad, É.C.T. Ramos, G.C. Coelho, C.A. Nunes, P.A. Suzuki, F. Ferreira, and P. Rogl, Evaluation of the Invariant 885 Reactions in the Ta-Rich Region of the Ta-B System, J Phase Equilibria Diffus., 2006, 27(5), p 452-455
cited as the source of values for this phase
doi:10.1016/0364-5916(91)90004-4 Lany Kaufman, Coupled thermochemical and phase diagram data for tantalum based binary alloys, Calphad 15, 243-259 (1991).
cited as the source of values for this phase

TA3B2_D5A (B–Ta)

Id: phase:b-ta:ta3b2-d5a; status assigned
Structure: Si2U3 · D5_a · tP10 · P4/mbm (127); type st:d5-a-si2u3-tp10; tier A: standard phase name; confidence high
Caveat: DFT agrees: on-hull mp-aaaaatvz and oqmd-18596, space group 127
Stoichiometry: B 0.4000, Ta 0.6000
Stability: stable in 2 of 2 calculated diagram(s): 300–2473.73 K, x(B) 0.4–0.4
Literature: 20 values (20 accepted) from 2 papers
Interactive: phase registry entry

Names (7): corpus: corpus:phase:b-ta:ta3b2-d5a
mp: mp:mp-aaaaatvz
oqmd: oqmd:oqmd-18596
paper: paper:10.1007/s11669-017-0603-2:Ta3B2, paper:10.1016/j.calphad.2018.08.012:Ta3B2
tdb: tdb:TaB-17OuY.tdb:TA3B2_D5A, tdb:TaB-18DaS.tdb:TA3B2_D5A

TDB models of TA3B2_D5A (2): PHASE and CONSTITUENT statements as written

TaB-17OuY.tdb: TA3B2_D5A, type code %, sha256 aaf8efce793d8609…

54: PHASE TA3B2_D5A % 2 3 2 !
55: CONST TA3B2_D5A : TA : B : !

TaB-18DaS.tdb: TA3B2_D5A, type code %, sha256 38b9b30e669c48fb…

51: PHASE TA3B2_D5A % 2 3 2 !
52: CONST TA3B2_D5A : TA : B : !

Example references (6 of 6; assessments first):

doi:10.1016/j.calphad.2018.08.012 Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-017-0603-2 Xuemei OuYang, Fucheng Yin, Jingxian Hu, Ye Liu, Zhaohui Long, Thermodynamic Modeling of B-Ta and B-C-Ta Systems, J. Phase Equilib. Diffus. 38, 874-886 (2017).
assessment that models this phase; reports values for this phase
doi:10.1007/bf02668242 H. Okamoto, Comment on B-Ta (boron-tantalum), JPE 14, 393-394 (1993).
cited as the source of values for this phase
doi:10.1007/bf02736442 V.M. Chad, É.C.T. Ramos, G.C. Coelho, C.A. Nunes, P.A. Suzuki, F. Ferreira, and P. Rogl, Evaluation of the Invariant 885 Reactions in the Ta-Rich Region of the Ta-B System, J Phase Equilibria Diffus., 2006, 27(5), p 452-455
cited as the source of values for this phase
doi:10.1016/0364-5916(91)90004-4 Lany Kaufman, Coupled thermochemical and phase diagram data for tantalum based binary alloys, Calphad 15, 243-259 (1991).
cited as the source of values for this phase
doi:10.1016/j.jallcom.2015.01.144 Xiaozheng Zhang, Erjun Zhao, Zhijian Wu, Prediction of new high pressure phase of TaB3: First-principles, Journal of Alloys and Compounds 632, 37-43 (2015).
cited as the source of values for this phase

TA3B4_D7B (B–Ta)

Id: phase:b-ta:ta3b4-d7b; status assigned
Structure: Ta3B4 · D7_b · oI14 · Immm (71); type st:d7-b-ta3b4-oi14; tier A: standard phase name; confidence high
Caveat: DFT agrees: on-hull mp-aaaaapac and oqmd-8470, space group 71
Stoichiometry: B 0.5714, Ta 0.4286
Stability: stable in 2 of 2 calculated diagram(s): 300–3305.36 K, x(B) 0.57143–0.57143
Literature: 18 values (18 accepted) from 2 papers
Interactive: phase registry entry

Names (7): corpus: corpus:phase:b-ta:ta3b4-d7b
mp: mp:mp-aaaaapac
oqmd: oqmd:oqmd-8470
paper: paper:10.1007/s11669-017-0603-2:Ta3B4, paper:10.1016/j.calphad.2018.08.012:Ta3B4
tdb: tdb:TaB-17OuY.tdb:TA3B4_D7B, tdb:TaB-18DaS.tdb:TA3B4_D7B

TDB models of TA3B4_D7B (2): PHASE and CONSTITUENT statements as written

TaB-17OuY.tdb: TA3B4_D7B, type code %, sha256 aaf8efce793d8609…

64: PHASE TA3B4_D7B % 2 3 4 !
65: CONST TA3B4_D7B : TA : B : !

TaB-18DaS.tdb: TA3B4_D7B, type code %, sha256 38b9b30e669c48fb…

71: PHASE TA3B4_D7B % 2 3 4 !
72: CONST TA3B4_D7B : TA : B : !

Example references (5 of 5; assessments first):

doi:10.1016/j.calphad.2018.08.012 Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-017-0603-2 Xuemei OuYang, Fucheng Yin, Jingxian Hu, Ye Liu, Zhaohui Long, Thermodynamic Modeling of B-Ta and B-C-Ta Systems, J. Phase Equilib. Diffus. 38, 874-886 (2017).
assessment that models this phase; reports values for this phase
doi:10.1016/j.jallcom.2015.01.144 Xiaozheng Zhang, Erjun Zhao, Zhijian Wu, Prediction of new high pressure phase of TaB3: First-principles, Journal of Alloys and Compounds 632, 37-43 (2015).
cited as the source of values for this phase
doi:10.1007/bf02668242 H. Okamoto, Comment on B-Ta (boron-tantalum), JPE 14, 393-394 (1993).
cited as the source of values for this phase
doi:10.1016/0364-5916(91)90004-4 Lany Kaufman, Coupled thermochemical and phase diagram data for tantalum based binary alloys, Calphad 15, 243-259 (1991).
cited as the source of values for this phase

TA5B6 (B–Ta)

Id: phase:b-ta:ta5b6; status assigned
Structure: V5B6 · oC22 · Cmmm (65); type st:v5b6-oc22; 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_mp, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: B 0.5455, Ta 0.4545
Stability: stable in 1 of 1 calculated diagram(s): 300–2848.48 K, x(B) 0.54545–0.54545
Literature: 1 values (1 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:b-ta:ta5b6
paper: paper:10.1016/j.calphad.2018.08.012:Ta5B6
tdb: tdb:TaB-18DaS.tdb:TA5B6

TDB models of TA5B6 (1): PHASE and CONSTITUENT statements as written

TaB-18DaS.tdb: TA5B6, type code %, sha256 38b9b30e669c48fb…

66: PHASE TA5B6 % 2 5 6 !
67: CONST TA5B6 : TA : B : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2018.08.012 Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018).
assessment that models this phase; reports values for this phase

TAB (B–Ta)

Id: phase:b-ta:tab; status needs_review
No structure assigned. Why: no_structure_token; polymorph_family:other phases of this system have the same composition
Candidate (dft_mp): Cmcm (63) — on-hull MP TaB at x(TA)=0.5000
Candidate (dft_oqmd): Cmcm (63) — on-hull OQMD B1 Ta1 at x(TA)=0.5000
Candidate (tdb_comment): CrB · oC8 · Cmcm, B33 — TaB-17OuY.tdb: 'Prototype CrB (oC8, Cmcm, B33), low T and FeB (oP8, Pnma, B27), high T'
Stoichiometry: B 0.5000, Ta 0.5000
Stability: stable in 1 of 1 calculated diagram(s): 300–3357.92 K, x(B) 0.5–0.5
Literature: 12 values (12 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:b-ta:tab
paper: paper:10.1007/s11669-017-0603-2:TaB
tdb: tdb:TaB-17OuY.tdb:TAB

TDB models of TAB (1): PHASE and CONSTITUENT statements as written

TaB-17OuY.tdb: TAB, type code %, sha256 aaf8efce793d8609…

59: PHASE TAB % 2 1 1 !
60: CONST TAB : TA : B : !

Example references (4 of 4; assessments first):

doi:10.1007/s11669-017-0603-2 Xuemei OuYang, Fucheng Yin, Jingxian Hu, Ye Liu, Zhaohui Long, Thermodynamic Modeling of B-Ta and B-C-Ta Systems, J. Phase Equilib. Diffus. 38, 874-886 (2017).
assessment that models this phase; reports values for this phase
doi:10.1007/bf02668242 H. Okamoto, Comment on B-Ta (boron-tantalum), JPE 14, 393-394 (1993).
cited as the source of values for this phase
doi:10.1016/0364-5916(91)90004-4 Lany Kaufman, Coupled thermochemical and phase diagram data for tantalum based binary alloys, Calphad 15, 243-259 (1991).
cited as the source of values for this phase
doi:10.1016/j.jallcom.2015.01.144 Xiaozheng Zhang, Erjun Zhao, Zhijian Wu, Prediction of new high pressure phase of TaB3: First-principles, Journal of Alloys and Compounds 632, 37-43 (2015).
cited as the source of values for this phase

TAB_B27 (B–Ta)

Id: phase:b-ta:tab-b27; status assigned
Structure: FeB · B27 · oP8 · Pnma (62); type st:b27-feb-op8; 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_structure_token, off_stoichiometric_model, structure_token_is_also_a_formula); structure as stated in the SGTE crystallographic table for this phase name and system
Stability: stable in 1 of 1 calculated diagram(s): 3008.42–3358.42 K, x(B) 0.48744–0.49581
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:b-ta:tab-b27
paper: paper:10.1016/j.calphad.2018.08.012:TaB(ht)
tdb: tdb:TaB-18DaS.tdb:TAB_B27

TDB models of TAB_B27 (1): PHASE and CONSTITUENT statements as written

TaB-18DaS.tdb: TAB_B27, type code %, sha256 38b9b30e669c48fb…

61: PHASE TAB_B27 % 2 1 1 !
62: CONST TAB_B27 : TA : B% VA : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2018.08.012 Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018).
assessment that models this phase; reports values for this phase
doi:10.1016/j.jallcom.2015.01.144 Xiaozheng Zhang, Erjun Zhao, Zhijian Wu, Prediction of new high pressure phase of TaB3: First-principles, Journal of Alloys and Compounds 632, 37-43 (2015).
cited as the source of values for this phase

TAB_B33 (B–Ta)

Id: phase:b-ta:tab-b33; status assigned
Structure: CrB · B33 · oC8 · Cmcm (63); type st:b33-crb-oc8; 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_structure_token, polymorph_family:other phases of this system have the same composition, structure_token_is_also_a_formula); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: B 0.5000, Ta 0.5000
Stability: stable in 1 of 1 calculated diagram(s): 300–3168.25 K, x(B) 0.5–0.5
Literature: 13 values (12 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:b-ta:tab-b33
paper: paper:10.1016/j.calphad.2018.08.012:TaB(rt)
tdb: tdb:TaB-18DaS.tdb:TAB_B33

TDB models of TAB_B33 (1): PHASE and CONSTITUENT statements as written

TaB-18DaS.tdb: TAB_B33, type code %, sha256 38b9b30e669c48fb…

56: PHASE TAB_B33 % 2 1 1 !
57: CONST TAB_B33 : TA : B : !

Example references (3 of 3; assessments first):

doi:10.1016/j.calphad.2018.08.012 Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018).
assessment that models this phase; reports values for this phase
doi:10.1016/j.jallcom.2015.01.144 Xiaozheng Zhang, Erjun Zhao, Zhijian Wu, Prediction of new high pressure phase of TaB3: First-principles, Journal of Alloys and Compounds 632, 37-43 (2015).
cited as the source of values for this phase
doi:10.1007/bf02736442 V.M. Chad, É.C.T. Ramos, G.C. Coelho, C.A. Nunes, P.A. Suzuki, F. Ferreira, and P. Rogl, Evaluation of the Invariant 885 Reactions in the Ta-Rich Region of the Ta-B System, J Phase Equilibria Diffus., 2006, 27(5), p 452-455
cited as the source of values for this phase

TAB2_C32 (B–Ta)

Id: phase:b-ta:tab2-c32; status assigned
Structure: AlB2 · C32 · hP3 · P6/mmm (191); type st:c32-alb2-hp3; tier A: standard phase name; confidence high
Caveat: partitioned order/disorder model in TaB-17OuY.tdb also describes the disordered state
Stability: stable in 2 of 2 calculated diagram(s): 300–3309.05 K, x(B) 0.66634–0.74398
Literature: 18 values (18 accepted) from 2 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:b-ta:tab2-c32
paper: paper:10.1007/s11669-017-0603-2:TaB2, paper:10.1016/j.calphad.2018.08.012:TaB2
tdb: tdb:TaB-17OuY.tdb:TAB2_C32, tdb:TaB-18DaS.tdb:TAB2_C32

TDB models of TAB2_C32 (2): PHASE and CONSTITUENT statements as written

TaB-17OuY.tdb: TAB2_C32, type code %, sha256 aaf8efce793d8609…

69: PHASE TAB2_C32 % 2 1 2 !
70: CONST TAB2_C32 : B TA% : B% TA : !

TaB-18DaS.tdb: TAB2_C32, type code %, sha256 38b9b30e669c48fb…

76: PHASE TAB2_C32 % 2 1 2 !
77: CONST TAB2_C32 : TA% VA : B% VA : !

Example references (6 of 6; assessments first):

doi:10.1007/s11669-017-0603-2 Xuemei OuYang, Fucheng Yin, Jingxian Hu, Ye Liu, Zhaohui Long, Thermodynamic Modeling of B-Ta and B-C-Ta Systems, J. Phase Equilib. Diffus. 38, 874-886 (2017).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.08.012 Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018).
assessment that models this phase; reports values for this phase
doi:10.1016/j.jallcom.2015.01.144 Xiaozheng Zhang, Erjun Zhao, Zhijian Wu, Prediction of new high pressure phase of TaB3: First-principles, Journal of Alloys and Compounds 632, 37-43 (2015).
cited as the source of values for this phase
doi:10.1007/bf02668242 H. Okamoto, Comment on B-Ta (boron-tantalum), JPE 14, 393-394 (1993).
cited as the source of values for this phase
doi:10.1016/0364-5916(91)90004-4 Lany Kaufman, Coupled thermochemical and phase diagram data for tantalum based binary alloys, Calphad 15, 243-259 (1991).
cited as the source of values for this phase
doi:10.1149/1.2428137 James M. Leitnaker, Melvin G. Bowman, Paul W. Gilles, High-Temperature Phase Studies in the Tantalum-Boron System between Ta and TaB, J. Electrochem. Soc. 108, 568 (1961).
cited as the source of 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}
}