# B–Nb phases

> B–Nb system: 11 phases (tier A 4, tier C 2, liquid 1, needs_review 4); 9 stable in a calculated diagram in the ORCHID phase registry, with names, structure type when the stored evidence supports an assignment under the stated tier rules, calculated stability, verbatim TDB PHASE/CONSTITUENT statements and example references.

HTML: https://data.orchid-project.org/phases/pages/B-NB.html · Markdown: https://data.orchid-project.org/phases/pages/B-NB.md

11 phases (tier A 4, tier C 2, liquid 1, needs_review 4); 9 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](https://orchid-project.org/phases/?q=B-NB) · [full JSON](https://data.orchid-project.org/phases/systems/B-NB.json) · [B–Nb system page](https://data.orchid-project.org/systems/B-NB.html) · [Markdown](https://data.orchid-project.org/phases/pages/B-NB.md) · [field reference](https://data.orchid-project.org/phases/SCHEMA.md)

Table: Phases of the B–Nb system (11)

| Phase | Structure | Basis | Stability (calculated) | Literature values | TDB models |
|---|---|---|---|---:|---:|
| [BETA_RHOMBO_B](#phase-b-nb-b-beta-rhombo); _phase:b-nb:b-beta-rhombo_ |  | needs_review | stable in 5 of 5 calculated diagram(s): 300–2363.97 K, x(B) 0.99521–1 | 4 | 5 |
| [BCC_A2](#phase-b-nb-bcc-a2); _phase:b-nb:bcc-a2_ | W · A2 · cI2 · Im-3m (229) | tier A: standard phase name | stable in 5 of 5 calculated diagram(s): 300–3999.99 K, x(B) 0–0.02696 | 9 | 5 |
| [FCC_A1](#phase-b-nb-fcc-a1); _phase:b-nb:fcc-a1_ | Cu · A1 · cF4 · Fm-3m (225) | tier A: standard phase name | not stable in 5 calculated diagram(s) | 0 | 5 |
| [HCP_A3](#phase-b-nb-hcp-a3); _phase:b-nb:hcp-a3_ | Mg · A3 · hP2 · P6_3/mmc (194) | tier A: standard phase name | not stable in 5 calculated diagram(s) | 0 | 5 |
| [LIQUID](#phase-b-nb-liquid); _phase:b-nb:liquid_ | liquid | liquid | stable in 5 of 5 calculated diagram(s): 2270.37–4000 K, x(B) 0–1 | 27 | 5 |
| [NB2B3](#phase-b-nb-nb2b3); _phase:b-nb:nb2b3_ | V2B3 · oC20 · Cmcm (63) | tier C: assessor-stated (Hallstedt 2025 crystallographic table) | stable in 4 of 4 calculated diagram(s): 300–2710 K, x(B) 0.6–0.6 | 2 | 4 |
| [NB3B2_D5A](#phase-b-nb-nb3b2-d5a); _phase:b-nb:nb3b2-d5a_ | Si2U3 · D5_a · tP10 · P4/mbm (127) | tier A: standard phase name | stable in 5 of 5 calculated diagram(s): 300–2460 K, x(B) 0.4–0.4 | 7 | 5 |
| [NB3B4_D7B](#phase-b-nb-nb3b4-d7b); _phase:b-nb:nb3b4-d7b_ |  | needs_review | stable in 5 of 5 calculated diagram(s): 300–3213.89 K, x(B) 0.57143–0.572 | 11 | 5 |
| [NB5B6](#phase-b-nb-nb5b6); _phase:b-nb:nb5b6_ |  | needs_review | stable in 5 of 5 calculated diagram(s): 300–3197.32 K, x(B) 0.545–0.54545 | 9 | 5 |
| [NBB_B33](#phase-b-nb-nbb-b33); _phase:b-nb:nbb-b33_ | CrB · B33 · oC8 · Cmcm (63) | tier C: assessor-stated (Hallstedt 2025 crystallographic table) | stable in 5 of 5 calculated diagram(s): 300–3193.41 K, x(B) 0.47539–0.5 | 18 | 5 |
| [NBB2_C32](#phase-b-nb-nbb2-c32); _phase:b-nb:nbb2-c32_ |  | needs_review | stable in 5 of 5 calculated diagram(s): 300–3320.66 K, x(B) 0.60952–0.72082 | 15 | 5 |

## BETA_RHOMBO_B (B–Nb)

- Id: `phase:b-nb: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 — NbB-07Pec.tdb: 'Prototype beta-B (hR105, R-3m)'
- Candidate (tdb_comment): beta-B · hR105 · R-3m — NbB-08Wit.tdb: 'Prototype beta-B (hR105, R-3m)'
- Candidate (tdb_comment): beta-B · hR105 · R-3m — NbB-08Yos.tdb: 'Prototype beta-B (hR105, R-3m)'
- Candidate (tdb_comment): beta-B · hR105 · R-3m — NbB-09Nak.tdb: 'Prototype beta-B (hR105, R-3m)'
- Candidate (tdb_comment): beta-B · hR105 · R-3m — NbB-23Pan.tdb: 'Prototype beta-B (hR105, R-3m)'
- Stability: stable in 5 of 5 calculated diagram(s): 300–2363.97 K, x(B) 0.99521–1
- Literature: 4 values (4 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:b-nb:b-beta-rhombo)

Names (8): _corpus: _corpus:phase:b-nb:b-beta-rhombo, corpus:phase:b-nb:beta-rhombo-b  
_paper: _paper:10.1016/j.jallcom.2006.10.034:(βB)  
_tdb: _tdb:NbB-07Pec.tdb:BETA_RHOMBO_B, tdb:NbB-08Wit.tdb:BETA_RHOMBO_B, tdb:NbB-08Yos.tdb:BETA_RHOMBO_B, tdb:NbB-09Nak.tdb:BETA_RHOMBO_B, tdb:NbB-23Pan.tdb:BETA_RHOMBO_B  


### TDB models of BETA_RHOMBO_B (5): PHASE and CONSTITUENT statements as written

[NbB-07Pec.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-07Pec.tdb): BETA_RHOMBO_B, type code %, sha256 `69bb1b9f802ec19a…`

~~~~text
46: PHASE BETA_RHOMBO_B % 1 1 !
47: CONST BETA_RHOMBO_B : B : !
~~~~

[NbB-08Wit.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Wit.tdb): BETA_RHOMBO_B, type code %, sha256 `2bc2c38fb45e540c…`

~~~~text
45: PHASE BETA_RHOMBO_B % 1 1 !
46: CONST BETA_RHOMBO_B : B NB : !
~~~~

[NbB-08Yos.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Yos.tdb): BETA_RHOMBO_B, type code %, sha256 `3dfd7add5bd6f596…`

~~~~text
44: PHASE BETA_RHOMBO_B % 1 1 !
45: CONST BETA_RHOMBO_B : B : !
~~~~

[NbB-09Nak.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-09Nak.tdb): BETA_RHOMBO_B, type code %, sha256 `a5b39b98692d5b70…`

~~~~text
46: PHASE BETA_RHOMBO_B % 1 1 !
47: CONST BETA_RHOMBO_B : B : !
~~~~

[NbB-23Pan.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-23Pan.tdb): BETA_RHOMBO_B, type code %, sha256 `71523b86a3d618ea…`

~~~~text
46: PHASE BETA_RHOMBO_B % 1 1 !
47: CONST BETA_RHOMBO_B : B NB : !
~~~~

Example references (6 of 6; assessments first): 

- [doi:10.1016/j.jallcom.2006.10.034](https://doi.org/10.1016/j.jallcom.2006.10.034) V.T. Witusiewicz, A.A. Bondar, U. Hecht, S. Rex, T.Ya. Velikanova, The Al–B–Nb–Ti system, Journal of Alloys and Compounds 448, 185-194 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.calphad.2023.102602](https://doi.org/10.1016/j.calphad.2023.102602) Y. Pan, X. Yang, Z. Fan, A. Liu, J. Zhang, F. Luo, Y. Du, L. Huang, Calphad, 82, 102602(2023).  
_assessment that models this phase_
- [doi:10.1016/j.intermet.2006.10.054](https://doi.org/10.1016/j.intermet.2006.10.054) Rockfeller Maciel Peçanha, Flávio Ferreira, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Bo Sundman, Thermodynamic modeling of the Nb–B system, Intermetallics 15, 999-1005 (2007).  
_assessment that models this phase_
- [doi:10.2320/matertrans.MC200820](https://doi.org/10.2320/matertrans.MC200820) Y. Nakama, H. Ohtani, M. Hasebe, Mater. Trans. (JIM), 50, 984-93(2009).  
_assessment that models this phase_
- [doi:10.2355/isijinternational.48.835](https://doi.org/10.2355/isijinternational.48.835) K. Yoshitomi, Y. Nakama, H. Ohtani, M. Hasebe, ISIJ Int., 48, 835-44(2008).  
_assessment that models this phase_
- [doi:10.1016/0364-5916(84)90026-9](https://doi.org/10.1016/0364-5916%2884%2990026-9) L. Kaufman, B. Uhrenius, D. Birnie, K. Taylor, Calphad 8 (1984) 25–66.  
_cited as the source of values for this phase_

## BCC_A2 (B–Nb)

- Id: `phase:b-nb: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 5 of 5 calculated diagram(s): 300–3999.99 K, x(B) 0–0.02696
- Literature: 9 values (9 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:b-nb:bcc-a2)

Names (7): _corpus: _corpus:phase:b-nb:bcc-a2  
_paper: _paper:10.1016/j.jallcom.2006.10.034:bcc  
_tdb: _tdb:NbB-07Pec.tdb:BCC_A2, tdb:NbB-08Wit.tdb:BCC_A2, tdb:NbB-08Yos.tdb:BCC_A2, tdb:NbB-09Nak.tdb:BCC_A2, tdb:NbB-23Pan.tdb:BCC_A2  


### TDB models of BCC_A2 (5): PHASE and CONSTITUENT statements as written

[NbB-07Pec.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-07Pec.tdb): BCC_A2, type code %B, sha256 `69bb1b9f802ec19a…`

~~~~text
36: PHASE BCC_A2 %B 2 1 3 !
37: CONST BCC_A2 : NB : B VA% : !
~~~~

[NbB-08Wit.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Wit.tdb): BCC_A2, type code %B, sha256 `2bc2c38fb45e540c…`

~~~~text
35: PHASE BCC_A2 %B 2 1 3 !
36: CONST BCC_A2 : NB : B VA% : !
~~~~

[NbB-08Yos.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Yos.tdb): BCC_A2, type code %B, sha256 `3dfd7add5bd6f596…`

~~~~text
34: PHASE BCC_A2 %B 2 1 3 !
35: CONST BCC_A2 : B NB% : VA : !
~~~~

[NbB-09Nak.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-09Nak.tdb): BCC_A2, type code %B, sha256 `a5b39b98692d5b70…`

~~~~text
36: PHASE BCC_A2 %B 2 1 3 !
37: CONST BCC_A2 : B NB% : VA : !
~~~~

[NbB-23Pan.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-23Pan.tdb): BCC_A2, type code %B, sha256 `71523b86a3d618ea…`

~~~~text
36: PHASE BCC_A2 %B 2 1 3 !
37: CONST BCC_A2 : NB : B VA% : !
~~~~

Example references (6 of 6; assessments first): 

- [doi:10.1016/j.jallcom.2006.10.034](https://doi.org/10.1016/j.jallcom.2006.10.034) V.T. Witusiewicz, A.A. Bondar, U. Hecht, S. Rex, T.Ya. Velikanova, The Al–B–Nb–Ti system, Journal of Alloys and Compounds 448, 185-194 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.calphad.2023.102602](https://doi.org/10.1016/j.calphad.2023.102602) Y. Pan, X. Yang, Z. Fan, A. Liu, J. Zhang, F. Luo, Y. Du, L. Huang, Calphad, 82, 102602(2023).  
_assessment that models this phase_
- [doi:10.1016/j.intermet.2006.10.054](https://doi.org/10.1016/j.intermet.2006.10.054) Rockfeller Maciel Peçanha, Flávio Ferreira, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Bo Sundman, Thermodynamic modeling of the Nb–B system, Intermetallics 15, 999-1005 (2007).  
_assessment that models this phase_
- [doi:10.2320/matertrans.MC200820](https://doi.org/10.2320/matertrans.MC200820) Y. Nakama, H. Ohtani, M. Hasebe, Mater. Trans. (JIM), 50, 984-93(2009).  
_assessment that models this phase_
- [doi:10.2355/isijinternational.48.835](https://doi.org/10.2355/isijinternational.48.835) K. Yoshitomi, Y. Nakama, H. Ohtani, M. Hasebe, ISIJ Int., 48, 835-44(2008).  
_assessment that models this phase_
- [doi:10.1016/0364-5916(84)90026-9](https://doi.org/10.1016/0364-5916%2884%2990026-9) L. Kaufman, B. Uhrenius, D. Birnie, K. Taylor, Calphad 8 (1984) 25–66.  
_cited as the source of values for this phase_

## FCC_A1 (B–Nb)

- Id: `phase:b-nb: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 5 calculated diagram(s)
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:b-nb:fcc-a1)

Names (6): _corpus: _corpus:phase:b-nb:fcc-a1  
_tdb: _tdb:NbB-07Pec.tdb:FCC_A1, tdb:NbB-08Wit.tdb:FCC_A1, tdb:NbB-08Yos.tdb:FCC_A1, tdb:NbB-09Nak.tdb:FCC_A1, tdb:NbB-23Pan.tdb:FCC_A1  


### TDB models of FCC_A1 (5): PHASE and CONSTITUENT statements as written

[NbB-07Pec.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-07Pec.tdb): FCC_A1, type code %A, sha256 `69bb1b9f802ec19a…`

~~~~text
31: PHASE FCC_A1 %A 2 1 1 !
32: CONST FCC_A1 : NB : B VA% : !
~~~~

[NbB-08Wit.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Wit.tdb): FCC_A1, type code %A, sha256 `2bc2c38fb45e540c…`

~~~~text
30: PHASE FCC_A1 %A 2 1 1 !
31: CONST FCC_A1 : NB : B VA% : !
~~~~

[NbB-08Yos.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Yos.tdb): FCC_A1, type code %A, sha256 `3dfd7add5bd6f596…`

~~~~text
29: PHASE FCC_A1 %A 2 1 1 !
30: CONST FCC_A1 : B NB : VA% : !
~~~~

[NbB-09Nak.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-09Nak.tdb): FCC_A1, type code %A, sha256 `a5b39b98692d5b70…`

~~~~text
31: PHASE FCC_A1 %A 2 1 1 !
32: CONST FCC_A1 : B NB : VA% : !
~~~~

[NbB-23Pan.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-23Pan.tdb): FCC_A1, type code %A, sha256 `71523b86a3d618ea…`

~~~~text
31: PHASE FCC_A1 %A 2 1 1 !
32: CONST FCC_A1 : NB : B VA% : !
~~~~

Example references (5 of 5; assessments first): 

- [doi:10.1016/j.calphad.2023.102602](https://doi.org/10.1016/j.calphad.2023.102602) Y. Pan, X. Yang, Z. Fan, A. Liu, J. Zhang, F. Luo, Y. Du, L. Huang, Calphad, 82, 102602(2023).  
_assessment that models this phase_
- [doi:10.1016/j.intermet.2006.10.054](https://doi.org/10.1016/j.intermet.2006.10.054) Rockfeller Maciel Peçanha, Flávio Ferreira, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Bo Sundman, Thermodynamic modeling of the Nb–B system, Intermetallics 15, 999-1005 (2007).  
_assessment that models this phase_
- [doi:10.1016/j.jallcom.2006.10.034](https://doi.org/10.1016/j.jallcom.2006.10.034) V.T. Witusiewicz, A.A. Bondar, U. Hecht, S. Rex, T.Ya. Velikanova, The Al–B–Nb–Ti system, Journal of Alloys and Compounds 448, 185-194 (2008).  
_assessment that models this phase_
- [doi:10.2320/matertrans.MC200820](https://doi.org/10.2320/matertrans.MC200820) Y. Nakama, H. Ohtani, M. Hasebe, Mater. Trans. (JIM), 50, 984-93(2009).  
_assessment that models this phase_
- [doi:10.2355/isijinternational.48.835](https://doi.org/10.2355/isijinternational.48.835) K. Yoshitomi, Y. Nakama, H. Ohtani, M. Hasebe, ISIJ Int., 48, 835-44(2008).  
_assessment that models this phase_

## HCP_A3 (B–Nb)

- Id: `phase:b-nb: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 5 calculated diagram(s)
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:b-nb:hcp-a3)

Names (6): _corpus: _corpus:phase:b-nb:hcp-a3  
_tdb: _tdb:NbB-07Pec.tdb:HCP_A3, tdb:NbB-08Wit.tdb:HCP_A3, tdb:NbB-08Yos.tdb:HCP_A3, tdb:NbB-09Nak.tdb:HCP_A3, tdb:NbB-23Pan.tdb:HCP_A3  


### TDB models of HCP_A3 (5): PHASE and CONSTITUENT statements as written

[NbB-07Pec.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-07Pec.tdb): HCP_A3, type code %A, sha256 `69bb1b9f802ec19a…`

~~~~text
41: PHASE HCP_A3 %A 2 1 0.5 !
42: CONST HCP_A3 : NB : B VA% : !
~~~~

[NbB-08Wit.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Wit.tdb): HCP_A3, type code %A, sha256 `2bc2c38fb45e540c…`

~~~~text
40: PHASE HCP_A3 %A 2 1 0.5 !
41: CONST HCP_A3 : NB : B VA% : !
~~~~

[NbB-08Yos.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Yos.tdb): HCP_A3, type code %A, sha256 `3dfd7add5bd6f596…`

~~~~text
39: PHASE HCP_A3 %A 2 1 0.5 !
40: CONST HCP_A3 : B NB : VA : !
~~~~

[NbB-09Nak.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-09Nak.tdb): HCP_A3, type code %A, sha256 `a5b39b98692d5b70…`

~~~~text
41: PHASE HCP_A3 %A 2 1 0.5 !
42: CONST HCP_A3 : B NB : VA : !
~~~~

[NbB-23Pan.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-23Pan.tdb): HCP_A3, type code %A, sha256 `71523b86a3d618ea…`

~~~~text
41: PHASE HCP_A3 %A 2 1 0.5 !
42: CONST HCP_A3 : NB : B VA% : !
~~~~

Example references (5 of 5; assessments first): 

- [doi:10.1016/j.calphad.2023.102602](https://doi.org/10.1016/j.calphad.2023.102602) Y. Pan, X. Yang, Z. Fan, A. Liu, J. Zhang, F. Luo, Y. Du, L. Huang, Calphad, 82, 102602(2023).  
_assessment that models this phase_
- [doi:10.1016/j.intermet.2006.10.054](https://doi.org/10.1016/j.intermet.2006.10.054) Rockfeller Maciel Peçanha, Flávio Ferreira, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Bo Sundman, Thermodynamic modeling of the Nb–B system, Intermetallics 15, 999-1005 (2007).  
_assessment that models this phase_
- [doi:10.1016/j.jallcom.2006.10.034](https://doi.org/10.1016/j.jallcom.2006.10.034) V.T. Witusiewicz, A.A. Bondar, U. Hecht, S. Rex, T.Ya. Velikanova, The Al–B–Nb–Ti system, Journal of Alloys and Compounds 448, 185-194 (2008).  
_assessment that models this phase_
- [doi:10.2320/matertrans.MC200820](https://doi.org/10.2320/matertrans.MC200820) Y. Nakama, H. Ohtani, M. Hasebe, Mater. Trans. (JIM), 50, 984-93(2009).  
_assessment that models this phase_
- [doi:10.2355/isijinternational.48.835](https://doi.org/10.2355/isijinternational.48.835) K. Yoshitomi, Y. Nakama, H. Ohtani, M. Hasebe, ISIJ Int., 48, 835-44(2008).  
_assessment that models this phase_

## LIQUID (B–Nb)

- Id: `phase:b-nb:liquid`; status `assigned`
- Structure: liquid; type `st:liquid`; liquid; confidence high
- Stability: stable in 5 of 5 calculated diagram(s): 2270.37–4000 K, x(B) 0–1
- Literature: 27 values (27 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:b-nb:liquid)

Names (7): _corpus: _corpus:phase:b-nb:liquid  
_paper: _paper:10.1016/j.jallcom.2006.10.034:L  
_tdb: _tdb:NbB-07Pec.tdb:LIQUID, tdb:NbB-08Wit.tdb:LIQUID, tdb:NbB-08Yos.tdb:LIQUID, tdb:NbB-09Nak.tdb:LIQUID, tdb:NbB-23Pan.tdb:LIQUID  


### TDB models of LIQUID (5): PHASE and CONSTITUENT statements as written

[NbB-07Pec.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-07Pec.tdb): LIQUID, type code %, sha256 `69bb1b9f802ec19a…`

~~~~text
26: PHASE LIQUID:L % 1 1 !
27: CONST LIQUID:L : B NB : !
~~~~

[NbB-08Wit.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Wit.tdb): LIQUID, type code %, sha256 `2bc2c38fb45e540c…`

~~~~text
25: PHASE LIQUID:L % 1 1 !
26: CONST LIQUID:L : B NB : !
~~~~

[NbB-08Yos.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Yos.tdb): LIQUID, type code %, sha256 `3dfd7add5bd6f596…`

~~~~text
24: PHASE LIQUID:L % 1 1 !
25: CONST LIQUID:L : B NB : !
~~~~

[NbB-09Nak.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-09Nak.tdb): LIQUID, type code %, sha256 `a5b39b98692d5b70…`

~~~~text
26: PHASE LIQUID:L % 1 1 !
27: CONST LIQUID:L : B NB : !
~~~~

[NbB-23Pan.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-23Pan.tdb): LIQUID, type code %, sha256 `71523b86a3d618ea…`

~~~~text
26: PHASE LIQUID:L % 1 1 !
27: CONST LIQUID:L : B NB : !
~~~~

Example references (6 of 6; assessments first): 

- [doi:10.1016/j.jallcom.2006.10.034](https://doi.org/10.1016/j.jallcom.2006.10.034) V.T. Witusiewicz, A.A. Bondar, U. Hecht, S. Rex, T.Ya. Velikanova, The Al–B–Nb–Ti system, Journal of Alloys and Compounds 448, 185-194 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.calphad.2023.102602](https://doi.org/10.1016/j.calphad.2023.102602) Y. Pan, X. Yang, Z. Fan, A. Liu, J. Zhang, F. Luo, Y. Du, L. Huang, Calphad, 82, 102602(2023).  
_assessment that models this phase_
- [doi:10.1016/j.intermet.2006.10.054](https://doi.org/10.1016/j.intermet.2006.10.054) Rockfeller Maciel Peçanha, Flávio Ferreira, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Bo Sundman, Thermodynamic modeling of the Nb–B system, Intermetallics 15, 999-1005 (2007).  
_assessment that models this phase_
- [doi:10.2320/matertrans.MC200820](https://doi.org/10.2320/matertrans.MC200820) Y. Nakama, H. Ohtani, M. Hasebe, Mater. Trans. (JIM), 50, 984-93(2009).  
_assessment that models this phase_
- [doi:10.2355/isijinternational.48.835](https://doi.org/10.2355/isijinternational.48.835) K. Yoshitomi, Y. Nakama, H. Ohtani, M. Hasebe, ISIJ Int., 48, 835-44(2008).  
_assessment that models this phase_
- [doi:10.1016/0364-5916(84)90026-9](https://doi.org/10.1016/0364-5916%2884%2990026-9) L. Kaufman, B. Uhrenius, D. Birnie, K. Taylor, Calphad 8 (1984) 25–66.  
_cited as the source of values for this phase_

## NB2B3 (B–Nb)

- Id: `phase:b-nb:nb2b3`; status `assigned`
- Structure: V2B3 · oC20 · Cmcm (63); type `st:v2b3-oc20`; 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](https://doi.org/10.1016/j.calphad.2025.102833)
- Caveat: not certain from the name or DFT alone (dft_space_group_63_matches_3_structure_types, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
- Stoichiometry: B 0.6000, Nb 0.4000
- Stability: stable in 4 of 4 calculated diagram(s): 300–2710 K, x(B) 0.6–0.6
- Literature: 2 values (2 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:b-nb:nb2b3)

Names (6): _corpus: _corpus:phase:b-nb:nb2b3  
_paper: _paper:10.1016/j.jallcom.2006.10.034:Nb2B3  
_tdb: _tdb:NbB-08Wit.tdb:NB2B3, tdb:NbB-08Yos.tdb:NB2B3, tdb:NbB-09Nak.tdb:NB2B3, tdb:NbB-23Pan.tdb:NB2B3  


### TDB models of NB2B3 (4): PHASE and CONSTITUENT statements as written

[NbB-08Wit.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Wit.tdb): NB2B3, type code %, sha256 `2bc2c38fb45e540c…`

~~~~text
70: PHASE NB2B3 % 2 2 3 !
71: CONST NB2B3 : NB : B : !
~~~~

[NbB-08Yos.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Yos.tdb): NB2B3, type code %, sha256 `3dfd7add5bd6f596…`

~~~~text
69: PHASE NB2B3 % 2 2 3 !
70: CONST NB2B3 : NB : B : !
~~~~

[NbB-09Nak.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-09Nak.tdb): NB2B3, type code %, sha256 `a5b39b98692d5b70…`

~~~~text
71: PHASE NB2B3 % 2 0.4 0.6 !
72: CONST NB2B3 : NB : B : !
~~~~

[NbB-23Pan.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-23Pan.tdb): NB2B3, type code %, sha256 `71523b86a3d618ea…`

~~~~text
71: PHASE NB2B3 % 2 2 3 !
72: CONST NB2B3 : NB : B : !
~~~~

Example references (4 of 4; assessments first): 

- [doi:10.1016/j.jallcom.2006.10.034](https://doi.org/10.1016/j.jallcom.2006.10.034) V.T. Witusiewicz, A.A. Bondar, U. Hecht, S. Rex, T.Ya. Velikanova, The Al–B–Nb–Ti system, Journal of Alloys and Compounds 448, 185-194 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.calphad.2023.102602](https://doi.org/10.1016/j.calphad.2023.102602) Y. Pan, X. Yang, Z. Fan, A. Liu, J. Zhang, F. Luo, Y. Du, L. Huang, Calphad, 82, 102602(2023).  
_assessment that models this phase_
- [doi:10.2320/matertrans.MC200820](https://doi.org/10.2320/matertrans.MC200820) Y. Nakama, H. Ohtani, M. Hasebe, Mater. Trans. (JIM), 50, 984-93(2009).  
_assessment that models this phase_
- [doi:10.2355/isijinternational.48.835](https://doi.org/10.2355/isijinternational.48.835) K. Yoshitomi, Y. Nakama, H. Ohtani, M. Hasebe, ISIJ Int., 48, 835-44(2008).  
_assessment that models this phase_

## NB3B2_D5A (B–Nb)

- Id: `phase:b-nb:nb3b2-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-aaaabept and oqmd-18595, space group 127
- Stoichiometry: B 0.4000, Nb 0.6000
- Stability: stable in 5 of 5 calculated diagram(s): 300–2460 K, x(B) 0.4–0.4
- Literature: 7 values (7 accepted) from 2 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:b-nb:nb3b2-d5a)

Names (10): _corpus: _corpus:phase:b-nb:nb3b2-d5a  
_mp: _mp:mp-aaaabept  
_oqmd: _oqmd:oqmd-18595  
_paper: _paper:10.1016/j.intermet.2006.10.054:Nb3B2, paper:10.1016/j.jallcom.2006.10.034:Nb3B2  
_tdb: _tdb:NbB-07Pec.tdb:NB3B2_D5A, tdb:NbB-08Wit.tdb:NB3B2_D5A, tdb:NbB-08Yos.tdb:NB3B2_D5A, tdb:NbB-09Nak.tdb:NB3B2_D5A, tdb:NbB-23Pan.tdb:NB3B2_D5A  


### TDB models of NB3B2_D5A (5): PHASE and CONSTITUENT statements as written

[NbB-07Pec.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-07Pec.tdb): NB3B2_D5A, type code %, sha256 `69bb1b9f802ec19a…`

~~~~text
51: PHASE NB3B2_D5A % 2 3 2 !
52: CONST NB3B2_D5A : NB : B : !
~~~~

[NbB-08Wit.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Wit.tdb): NB3B2_D5A, type code %, sha256 `2bc2c38fb45e540c…`

~~~~text
50: PHASE NB3B2_D5A % 2 3 2 !
51: CONST NB3B2_D5A : NB : B : !
~~~~

[NbB-08Yos.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Yos.tdb): NB3B2_D5A, type code %, sha256 `3dfd7add5bd6f596…`

~~~~text
49: PHASE NB3B2_D5A % 2 3 2 !
50: CONST NB3B2_D5A : NB : B : !
~~~~

[NbB-09Nak.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-09Nak.tdb): NB3B2_D5A, type code %, sha256 `a5b39b98692d5b70…`

~~~~text
51: PHASE NB3B2_D5A % 2 0.6 0.4 !
52: CONST NB3B2_D5A : NB : B : !
~~~~

[NbB-23Pan.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-23Pan.tdb): NB3B2_D5A, type code %, sha256 `71523b86a3d618ea…`

~~~~text
51: PHASE NB3B2_D5A % 2 3 2 !
52: CONST NB3B2_D5A : NB : B : !
~~~~

Example references (7 of 7; assessments first): 

- [doi:10.1016/j.jallcom.2006.10.034](https://doi.org/10.1016/j.jallcom.2006.10.034) V.T. Witusiewicz, A.A. Bondar, U. Hecht, S. Rex, T.Ya. Velikanova, The Al–B–Nb–Ti system, Journal of Alloys and Compounds 448, 185-194 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.intermet.2006.10.054](https://doi.org/10.1016/j.intermet.2006.10.054) Rockfeller Maciel Peçanha, Flávio Ferreira, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Bo Sundman, Thermodynamic modeling of the Nb–B system, Intermetallics 15, 999-1005 (2007).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.calphad.2023.102602](https://doi.org/10.1016/j.calphad.2023.102602) Y. Pan, X. Yang, Z. Fan, A. Liu, J. Zhang, F. Luo, Y. Du, L. Huang, Calphad, 82, 102602(2023).  
_assessment that models this phase_
- [doi:10.2320/matertrans.MC200820](https://doi.org/10.2320/matertrans.MC200820) Y. Nakama, H. Ohtani, M. Hasebe, Mater. Trans. (JIM), 50, 984-93(2009).  
_assessment that models this phase_
- [doi:10.2355/isijinternational.48.835](https://doi.org/10.2355/isijinternational.48.835) K. Yoshitomi, Y. Nakama, H. Ohtani, M. Hasebe, ISIJ Int., 48, 835-44(2008).  
_assessment that models this phase_
- [doi:10.1007/bf00794439](https://doi.org/10.1007/bf00794439) A. V. Blinder, A. S. Bolgar, Heat capacity and enthalpy of transition-metal borides in a broad range of temperatures, Powder Metall Met Ceram 30, 1053-1056 (1991).  
_cited as the source of values for this phase_
- [doi:10.1016/0364-5916(84)90026-9](https://doi.org/10.1016/0364-5916%2884%2990026-9) L. Kaufman, B. Uhrenius, D. Birnie, K. Taylor, Calphad 8 (1984) 25–66.  
_cited as the source of values for this phase_

## NB3B4_D7B (B–Nb)

- Id: `phase:b-nb:nb3b4-d7b`; status `needs_review`
- No structure assigned. Why: assessment_declared_blocked_by:models_disagree_on_composition; models_disagree_on_composition; stoichiometry_contradicts_D7_b:NbB-09Nak.tdb
- Candidate (literature_printed): Ta3B4 · oI14 — printed with a label mapped to this phase
- Candidate (name_token): Ta3B4 · D7_b · oI14 · Immm (71) — Strukturbericht/word 'D7B' in the TDB name
- Candidate (sgte_mmc2): Ta3B4 · D7_b · oI14 · Immm (71) — Hallstedt 2025 mmc2 row for NB3B4_D7B: Nb3B4
- Candidate (tdb_comment): Ta3B4 · oI14 · Immm — NbB-07Pec.tdb: 'Prototype Ta3B4 (oI14, Immm)'
- Candidate (tdb_comment): Ta3B4 · oI14 · Immm — NbB-08Wit.tdb: 'Prototype Ta3B4 (oI14, Immm)'
- Candidate (tdb_comment): Ta3B4 · oI14 · Immm — NbB-08Yos.tdb: 'Prototype Ta3B4 (oI14, Immm)'
- Candidate (tdb_comment): Ta3B4 · oI14 · Immm — NbB-09Nak.tdb: 'Prototype Ta3B4 (oI14, Immm)'
- Candidate (tdb_comment): Ta3B4 · oI14 · Immm — NbB-23Pan.tdb: 'Prototype Ta3B4 (oI14, Immm)'
- Stability: stable in 5 of 5 calculated diagram(s): 300–3213.89 K, x(B) 0.57143–0.572
- Literature: 11 values (11 accepted) from 2 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:b-nb:nb3b4-d7b)

Names (8): _corpus: _corpus:phase:b-nb:nb3b4-d7b  
_paper: _paper:10.1016/j.intermet.2006.10.054:Nb3B4, paper:10.1016/j.jallcom.2006.10.034:Nb3B4  
_tdb: _tdb:NbB-07Pec.tdb:NB3B4_D7B, tdb:NbB-08Wit.tdb:NB3B4_D7B, tdb:NbB-08Yos.tdb:NB3B4_D7B, tdb:NbB-09Nak.tdb:NB3B4_D7B, tdb:NbB-23Pan.tdb:NB3B4_D7B  


### TDB models of NB3B4_D7B (5): PHASE and CONSTITUENT statements as written

[NbB-07Pec.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-07Pec.tdb): NB3B4_D7B, type code %, sha256 `69bb1b9f802ec19a…`

~~~~text
66: PHASE NB3B4_D7B % 2 3 4 !
67: CONST NB3B4_D7B : NB : B : !
~~~~

[NbB-08Wit.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Wit.tdb): NB3B4_D7B, type code %, sha256 `2bc2c38fb45e540c…`

~~~~text
65: PHASE NB3B4_D7B % 2 3 4 !
66: CONST NB3B4_D7B : NB : B : !
~~~~

[NbB-08Yos.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Yos.tdb): NB3B4_D7B, type code %, sha256 `3dfd7add5bd6f596…`

~~~~text
64: PHASE NB3B4_D7B % 2 3 4 !
65: CONST NB3B4_D7B : NB : B : !
~~~~

[NbB-09Nak.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-09Nak.tdb): NB3B4_D7B, type code %, sha256 `a5b39b98692d5b70…`

~~~~text
66: PHASE NB3B4_D7B % 2 0.428 0.572 !
67: CONST NB3B4_D7B : NB : B : !
~~~~

[NbB-23Pan.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-23Pan.tdb): NB3B4_D7B, type code %, sha256 `71523b86a3d618ea…`

~~~~text
66: PHASE NB3B4_D7B % 2 3 4 !
67: CONST NB3B4_D7B : NB : B : !
~~~~

Example references (7 of 7; assessments first): 

- [doi:10.1016/j.jallcom.2006.10.034](https://doi.org/10.1016/j.jallcom.2006.10.034) V.T. Witusiewicz, A.A. Bondar, U. Hecht, S. Rex, T.Ya. Velikanova, The Al–B–Nb–Ti system, Journal of Alloys and Compounds 448, 185-194 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.intermet.2006.10.054](https://doi.org/10.1016/j.intermet.2006.10.054) Rockfeller Maciel Peçanha, Flávio Ferreira, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Bo Sundman, Thermodynamic modeling of the Nb–B system, Intermetallics 15, 999-1005 (2007).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.calphad.2023.102602](https://doi.org/10.1016/j.calphad.2023.102602) Y. Pan, X. Yang, Z. Fan, A. Liu, J. Zhang, F. Luo, Y. Du, L. Huang, Calphad, 82, 102602(2023).  
_assessment that models this phase_
- [doi:10.2320/matertrans.MC200820](https://doi.org/10.2320/matertrans.MC200820) Y. Nakama, H. Ohtani, M. Hasebe, Mater. Trans. (JIM), 50, 984-93(2009).  
_assessment that models this phase_
- [doi:10.2355/isijinternational.48.835](https://doi.org/10.2355/isijinternational.48.835) K. Yoshitomi, Y. Nakama, H. Ohtani, M. Hasebe, ISIJ Int., 48, 835-44(2008).  
_assessment that models this phase_
- [doi:10.1016/0364-5916(84)90026-9](https://doi.org/10.1016/0364-5916%2884%2990026-9) L. Kaufman, B. Uhrenius, D. Birnie, K. Taylor, Calphad 8 (1984) 25–66.  
_cited as the source of values for this phase_
- [doi:10.1007/bf00794439](https://doi.org/10.1007/bf00794439) A. V. Blinder, A. S. Bolgar, Heat capacity and enthalpy of transition-metal borides in a broad range of temperatures, Powder Metall Met Ceram 30, 1053-1056 (1991).  
_cited as the source of values for this phase_

## NB5B6 (B–Nb)

- Id: `phase:b-nb:nb5b6`; status `needs_review`
- No structure assigned. Why: assessment_declared_blocked_by:models_disagree_on_composition; models_disagree_on_composition; no_structure_token
- Candidate (literature_printed): V5B6 · oC22 — printed with a label mapped to this phase
- Candidate (sgte_mmc2): V5B6 · oC22 · Cmmm (65) — Hallstedt 2025 mmc2 row for NB5B6: Nb5B6
- Candidate (tdb_comment): V5B6 · oC22 · Cmmm — NbB-07Pec.tdb: 'Prototype V5B6 (oC22, Cmmm)'
- Candidate (tdb_comment): V5B6 · oC22 · Cmmm — NbB-08Wit.tdb: 'Prototype V5B6 (oC22, Cmmm)'
- Candidate (tdb_comment): V5B6 · oC22 · Cmmm — NbB-08Yos.tdb: 'Prototype V5B6 (oC22, Cmmm)'
- Candidate (tdb_comment): V5B6 · oC22 · Cmmm — NbB-09Nak.tdb: 'Prototype V5B6 (oC22, Cmmm)'
- Candidate (tdb_comment): V5B6 · oC22 · Cmmm — NbB-23Pan.tdb: 'Prototype V5B6 (oC22, Cmmm)'
- Stability: stable in 5 of 5 calculated diagram(s): 300–3197.32 K, x(B) 0.545–0.54545
- Literature: 9 values (9 accepted) from 2 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:b-nb:nb5b6)

Names (8): _corpus: _corpus:phase:b-nb:nb5b6  
_paper: _paper:10.1016/j.intermet.2006.10.054:Nb5B6, paper:10.1016/j.jallcom.2006.10.034:Nb5B6  
_tdb: _tdb:NbB-07Pec.tdb:NB5B6, tdb:NbB-08Wit.tdb:NB5B6, tdb:NbB-08Yos.tdb:NB5B6, tdb:NbB-09Nak.tdb:NB5B6, tdb:NbB-23Pan.tdb:NB5B6  


### TDB models of NB5B6 (5): PHASE and CONSTITUENT statements as written

[NbB-07Pec.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-07Pec.tdb): NB5B6, type code %, sha256 `69bb1b9f802ec19a…`

~~~~text
61: PHASE NB5B6 % 2 5 6 !
62: CONST NB5B6 : NB : B : !
~~~~

[NbB-08Wit.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Wit.tdb): NB5B6, type code %, sha256 `2bc2c38fb45e540c…`

~~~~text
60: PHASE NB5B6 % 2 5 6 !
61: CONST NB5B6 : NB : B : !
~~~~

[NbB-08Yos.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Yos.tdb): NB5B6, type code %, sha256 `3dfd7add5bd6f596…`

~~~~text
59: PHASE NB5B6 % 2 5 6 !
60: CONST NB5B6 : NB : B : !
~~~~

[NbB-09Nak.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-09Nak.tdb): NB5B6, type code %, sha256 `a5b39b98692d5b70…`

~~~~text
61: PHASE NB5B6 % 2 0.455 0.545 !
62: CONST NB5B6 : NB : B : !
~~~~

[NbB-23Pan.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-23Pan.tdb): NB5B6, type code %, sha256 `71523b86a3d618ea…`

~~~~text
61: PHASE NB5B6 % 2 5 6 !
62: CONST NB5B6 : NB : B : !
~~~~

Example references (6 of 6; assessments first): 

- [doi:10.1016/j.intermet.2006.10.054](https://doi.org/10.1016/j.intermet.2006.10.054) Rockfeller Maciel Peçanha, Flávio Ferreira, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Bo Sundman, Thermodynamic modeling of the Nb–B system, Intermetallics 15, 999-1005 (2007).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.jallcom.2006.10.034](https://doi.org/10.1016/j.jallcom.2006.10.034) V.T. Witusiewicz, A.A. Bondar, U. Hecht, S. Rex, T.Ya. Velikanova, The Al–B–Nb–Ti system, Journal of Alloys and Compounds 448, 185-194 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.calphad.2023.102602](https://doi.org/10.1016/j.calphad.2023.102602) Y. Pan, X. Yang, Z. Fan, A. Liu, J. Zhang, F. Luo, Y. Du, L. Huang, Calphad, 82, 102602(2023).  
_assessment that models this phase_
- [doi:10.2320/matertrans.MC200820](https://doi.org/10.2320/matertrans.MC200820) Y. Nakama, H. Ohtani, M. Hasebe, Mater. Trans. (JIM), 50, 984-93(2009).  
_assessment that models this phase_
- [doi:10.2355/isijinternational.48.835](https://doi.org/10.2355/isijinternational.48.835) K. Yoshitomi, Y. Nakama, H. Ohtani, M. Hasebe, ISIJ Int., 48, 835-44(2008).  
_assessment that models this phase_
- [doi:10.1016/0022-5088(90)90170-o](https://doi.org/10.1016/0022-5088%2890%2990170-o) H. Bolmgren, T. Lundström, A new binary boride, Nb5B6, Journal of the Less Common Metals 159, L25-L27 (1990).  
_cited as the source of values for this phase_

## NBB_B33 (B–Nb)

- Id: `phase:b-nb:nbb-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](https://doi.org/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 5 of 5 calculated diagram(s): 300–3193.41 K, x(B) 0.47539–0.5
- Literature: 18 values (18 accepted) from 2 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:b-nb:nbb-b33)

Names (8): _corpus: _corpus:phase:b-nb:nbb-b33  
_paper: _paper:10.1016/j.intermet.2006.10.054:NbB, paper:10.1016/j.jallcom.2006.10.034:NbB  
_tdb: _tdb:NbB-07Pec.tdb:NBB_B33, tdb:NbB-08Wit.tdb:NBB_B33, tdb:NbB-08Yos.tdb:NBB_B33, tdb:NbB-09Nak.tdb:NBB_B33, tdb:NbB-23Pan.tdb:NBB_B33  


### TDB models of NBB_B33 (5): PHASE and CONSTITUENT statements as written

[NbB-07Pec.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-07Pec.tdb): NBB_B33, type code %, sha256 `69bb1b9f802ec19a…`

~~~~text
56: PHASE NBB_B33 % 2 1 1 !
57: CONST NBB_B33 : NB : B : !
~~~~

[NbB-08Wit.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Wit.tdb): NBB_B33, type code %, sha256 `2bc2c38fb45e540c…`

~~~~text
55: PHASE NBB_B33 % 2 1 1 !
56: CONST NBB_B33 : NB : B% NB : !
~~~~

[NbB-08Yos.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Yos.tdb): NBB_B33, type code %, sha256 `3dfd7add5bd6f596…`

~~~~text
54: PHASE NBB_B33 % 2 1 1 !
55: CONST NBB_B33 : NB : B : !
~~~~

[NbB-09Nak.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-09Nak.tdb): NBB_B33, type code %, sha256 `a5b39b98692d5b70…`

~~~~text
56: PHASE NBB_B33 % 2 0.5 0.5 !
57: CONST NBB_B33 : NB : B : !
~~~~

[NbB-23Pan.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-23Pan.tdb): NBB_B33, type code %, sha256 `71523b86a3d618ea…`

~~~~text
56: PHASE NBB_B33 % 2 1 1 !
57: CONST NBB_B33 : NB% VA : B% VA : !
~~~~

Example references (7 of 7; assessments first): 

- [doi:10.1016/j.jallcom.2006.10.034](https://doi.org/10.1016/j.jallcom.2006.10.034) V.T. Witusiewicz, A.A. Bondar, U. Hecht, S. Rex, T.Ya. Velikanova, The Al–B–Nb–Ti system, Journal of Alloys and Compounds 448, 185-194 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.intermet.2006.10.054](https://doi.org/10.1016/j.intermet.2006.10.054) Rockfeller Maciel Peçanha, Flávio Ferreira, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Bo Sundman, Thermodynamic modeling of the Nb–B system, Intermetallics 15, 999-1005 (2007).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.calphad.2023.102602](https://doi.org/10.1016/j.calphad.2023.102602) Y. Pan, X. Yang, Z. Fan, A. Liu, J. Zhang, F. Luo, Y. Du, L. Huang, Calphad, 82, 102602(2023).  
_assessment that models this phase_
- [doi:10.2320/matertrans.MC200820](https://doi.org/10.2320/matertrans.MC200820) Y. Nakama, H. Ohtani, M. Hasebe, Mater. Trans. (JIM), 50, 984-93(2009).  
_assessment that models this phase_
- [doi:10.2355/isijinternational.48.835](https://doi.org/10.2355/isijinternational.48.835) K. Yoshitomi, Y. Nakama, H. Ohtani, M. Hasebe, ISIJ Int., 48, 835-44(2008).  
_assessment that models this phase_
- [doi:10.1016/0364-5916(84)90026-9](https://doi.org/10.1016/0364-5916%2884%2990026-9) L. Kaufman, B. Uhrenius, D. Birnie, K. Taylor, Calphad 8 (1984) 25–66.  
_cited as the source of values for this phase_
- [doi:10.1007/bf00794439](https://doi.org/10.1007/bf00794439) A. V. Blinder, A. S. Bolgar, Heat capacity and enthalpy of transition-metal borides in a broad range of temperatures, Powder Metall Met Ceram 30, 1053-1056 (1991).  
_cited as the source of values for this phase_

## NBB2_C32 (B–Nb)

- Id: `phase:b-nb:nbb2-c32`; status `needs_review`
- No structure assigned. Why: assessment_declared_blocked_by:site_ratios_contradict_C32; site_ratios_contradict_C32:NbB-09Nak.tdb
- Candidate (literature_printed): AlB2 · hP3 — printed with a label mapped to this phase
- Candidate (name_token): AlB2 · C32 · hP3 · P6/mmm (191) — Strukturbericht/word 'C32' in the TDB name
- Candidate (sgte_mmc2): AlB2 · C32 · hP3 · P6/mmm (191) — Hallstedt 2025 mmc2 row for NBB2_C32: NbB2
- Candidate (tdb_comment): AlB2 · hP3 · P6/mmm — NbB-07Pec.tdb: 'Prototype AlB2 (hP3, P6/mmm)'
- Candidate (tdb_comment): AlB2 · hP3 · P6/mmm — NbB-08Wit.tdb: 'Prototype AlB2 (hP3, P6/mmm)'
- Candidate (tdb_comment): AlB2 · hP3 · P6/mmm — NbB-08Yos.tdb: 'Prototype AlB2 (hP3, P6/mmm)'
- Candidate (tdb_comment): AlB2 · hP3 · P6/mmm — NbB-09Nak.tdb: 'Prototype AlB2 (hP3, P6/mmm)'
- Candidate (tdb_comment): AlB2 · hP3 · P6/mmm — NbB-23Pan.tdb: 'Prototype AlB2 (hP3, P6/mmm)'
- Stability: stable in 5 of 5 calculated diagram(s): 300–3320.66 K, x(B) 0.60952–0.72082
- Literature: 15 values (15 accepted) from 2 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:b-nb:nbb2-c32)

Names (8): _corpus: _corpus:phase:b-nb:nbb2-c32  
_paper: _paper:10.1016/j.intermet.2006.10.054:NbB2, paper:10.1016/j.jallcom.2006.10.034:NbB2  
_tdb: _tdb:NbB-07Pec.tdb:NBB2_C32, tdb:NbB-08Wit.tdb:NBB2_C32, tdb:NbB-08Yos.tdb:NBB2_C32, tdb:NbB-09Nak.tdb:NBB2_C32, tdb:NbB-23Pan.tdb:NBB2_C32  


### TDB models of NBB2_C32 (5): PHASE and CONSTITUENT statements as written

[NbB-07Pec.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-07Pec.tdb): NBB2_C32, type code %, sha256 `69bb1b9f802ec19a…`

~~~~text
71: PHASE NBB2_C32 % 2 1 2 !
72: CONST NBB2_C32 : NB VA : B VA : !
~~~~

[NbB-08Wit.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Wit.tdb): NBB2_C32, type code %, sha256 `2bc2c38fb45e540c…`

~~~~text
75: PHASE NBB2_C32 % 2 1 2 !
76: CONST NBB2_C32 : B NB% : B% NB : !
~~~~

[NbB-08Yos.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-08Yos.tdb): NBB2_C32, type code %, sha256 `3dfd7add5bd6f596…`

~~~~text
74: PHASE NBB2_C32 % 2 1 2 !
75: CONST NBB2_C32 : NB VA : B VA : !
~~~~

[NbB-09Nak.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-09Nak.tdb): NBB2_C32, type code %, sha256 `a5b39b98692d5b70…`

~~~~text
76: PHASE NBB2_C32 % 2 0.333 0.667 !
77: CONST NBB2_C32 : NB VA : B VA : !
~~~~

[NbB-23Pan.tdb](https://orchid-project.org/data/databases/sgte-binary/NbB-23Pan.tdb): NBB2_C32, type code %, sha256 `71523b86a3d618ea…`

~~~~text
76: PHASE NBB2_C32 % 2 1 2 !
77: CONST NBB2_C32 : B NB% : B% NB : !
~~~~

Example references (7 of 7; assessments first): 

- [doi:10.1016/j.jallcom.2006.10.034](https://doi.org/10.1016/j.jallcom.2006.10.034) V.T. Witusiewicz, A.A. Bondar, U. Hecht, S. Rex, T.Ya. Velikanova, The Al–B–Nb–Ti system, Journal of Alloys and Compounds 448, 185-194 (2008).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.intermet.2006.10.054](https://doi.org/10.1016/j.intermet.2006.10.054) Rockfeller Maciel Peçanha, Flávio Ferreira, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Bo Sundman, Thermodynamic modeling of the Nb–B system, Intermetallics 15, 999-1005 (2007).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.calphad.2023.102602](https://doi.org/10.1016/j.calphad.2023.102602) Y. Pan, X. Yang, Z. Fan, A. Liu, J. Zhang, F. Luo, Y. Du, L. Huang, Calphad, 82, 102602(2023).  
_assessment that models this phase_
- [doi:10.2320/matertrans.MC200820](https://doi.org/10.2320/matertrans.MC200820) Y. Nakama, H. Ohtani, M. Hasebe, Mater. Trans. (JIM), 50, 984-93(2009).  
_assessment that models this phase_
- [doi:10.2355/isijinternational.48.835](https://doi.org/10.2355/isijinternational.48.835) K. Yoshitomi, Y. Nakama, H. Ohtani, M. Hasebe, ISIJ Int., 48, 835-44(2008).  
_assessment that models this phase_
- [doi:10.1016/0364-5916(84)90026-9](https://doi.org/10.1016/0364-5916%2884%2990026-9) L. Kaufman, B. Uhrenius, D. Birnie, K. Taylor, Calphad 8 (1984) 25–66.  
_cited as the source of values for this phase_
- [doi:10.1021/j100805a030](https://doi.org/10.1021/j100805a030) Edgar F. Westrum, NbB\<sub>1.963\</sub>: THE HEAT CAPACITY AND THERMODYNAMIC PROPERTIES FROM 5 TO 350°K., J. Phys. Chem. 67, 2385-2387 (1963).  
_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). https://doi.org/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). https://doi.org/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.

```bibtex
@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}
}
```

---

Derived data CC BY 4.0 ([licence](https://creativecommons.org/licenses/by/4.0/)): cite the ORCHID phase registry and the sources named on the page (TDB assessments, Hallstedt 2025, Materials Project, OQMD). TDB statements are quoted as written; parameter expressions are not reproduced. Field reference: [SCHEMA.md](https://data.orchid-project.org/phases/SCHEMA.md). Machine-readable guide: [llms.txt](https://data.orchid-project.org/llms.txt).