# Bi–Pb phases > Bi–Pb system: 5 phases (tier A 4, liquid 1); 4 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/BI-PB.html · Markdown: https://data.orchid-project.org/phases/pages/BI-PB.md 5 phases (tier A 4, liquid 1); 4 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=BI-PB) · [full JSON](https://data.orchid-project.org/phases/systems/BI-PB.json) · [Bi–Pb system page](https://data.orchid-project.org/systems/BI-PB.html) · [Markdown](https://data.orchid-project.org/phases/pages/BI-PB.md) · [field reference](https://data.orchid-project.org/phases/SCHEMA.md) Table: Phases of the Bi–Pb system (5) | Phase | Structure | Basis | Stability (calculated) | Literature values | TDB models | |---|---|---|---|---:|---:| | [RHOMBOHEDRAL_A7](#phase-bi-pb-a7-rhombohedral); _phase:bi-pb:a7-rhombohedral_ | alpha-As · A7 · hR2 · R-3m (166) | tier A: standard phase name | stable in 4 of 4 calculated diagram(s): 300–544.55 K, x(Pb) 0–0.0048 | 0 | 4 | | [BCC_A2](#phase-bi-pb-bcc-a2); _phase:bi-pb:bcc-a2_ | W · A2 · cI2 · Im-3m (229) | tier A: standard phase name | not stable in 4 calculated diagram(s) | 0 | 4 | | [FCC_A1](#phase-bi-pb-fcc-a1); _phase:bi-pb:fcc-a1_ | Cu · A1 · cF4 · Fm-3m (225) | tier A: standard phase name | stable in 4 of 4 calculated diagram(s): 300–2499.36 K, x(Pb) 0.76884–1 | 0 | 4 | | [HCP_A3](#phase-bi-pb-hcp-a3); _phase:bi-pb:hcp-a3_ | Mg · A3 · hP2 · P6_3/mmc (194) | tier A: standard phase name | stable in 4 of 4 calculated diagram(s): 300–459.3 K, x(Pb) 0.57133–0.75363 | 0 | 4 | | [LIQUID](#phase-bi-pb-liquid); _phase:bi-pb:liquid_ | liquid | liquid | stable in 4 of 4 calculated diagram(s): 398.14–2500 K, x(Pb) 0–1 | 0 | 4 | ## RHOMBOHEDRAL_A7 (Bi–Pb) - Id: `phase:bi-pb:a7-rhombohedral`; status `assigned` - Structure: alpha-As · A7 · hR2 · R-3m (166); type `st:a7-alpha-as-hr2`; tier A: standard phase name; confidence high - Stability: stable in 4 of 4 calculated diagram(s): 300–544.55 K, x(Pb) 0–0.0048 - Literature: 0 values (0 accepted) from 0 papers - Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:bi-pb:a7-rhombohedral) Names (5): _corpus: _corpus:phase:bi-pb:a7-rhombohedral _tdb: _tdb:BiPb-17Gie.tdb:RHOMBOHEDRAL_A7, tdb:BiPb-21Aga.tdb:RHOMBOHEDRAL_A7, tdb:BiPb-98Boa-LB.tdb:RHOMBOHEDRAL_A7, tdb:BiPb-98Yoo.tdb:RHOMBOHEDRAL_A7 ### TDB models of RHOMBOHEDRAL_A7 (4): PHASE and CONSTITUENT statements as written [BiPb-17Gie.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-17Gie.tdb): RHOMBOHEDRAL_A7, type code %, sha256 `9ba301ea84eb981a…` ~~~~text 42: PHASE RHOMBOHEDRAL_A7 % 1 1 ! 43: CONST RHOMBOHEDRAL_A7 : BI% PB : ! ~~~~ [BiPb-21Aga.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-21Aga.tdb): RHOMBOHEDRAL_A7, type code %, sha256 `767bd5aeaed33a7b…` ~~~~text 47: PHASE RHOMBOHEDRAL_A7 % 1 1 ! 48: CONST RHOMBOHEDRAL_A7 : BI% PB : ! ~~~~ [BiPb-98Boa-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-98Boa-LB.tdb): RHOMBOHEDRAL_A7, type code %, sha256 `c36b3e9ef4935609…` ~~~~text 44: PHASE RHOMBOHEDRAL_A7 % 1 1 ! 45: CONST RHOMBOHEDRAL_A7 : BI% PB : ! ~~~~ [BiPb-98Yoo.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-98Yoo.tdb): RHOMBOHEDRAL_A7, type code %, sha256 `a29e66212cd9bf01…` ~~~~text 40: PHASE RHOMBOHEDRAL_A7 % 1 1 ! 41: CONST RHOMBOHEDRAL_A7 : BI% PB : ! ~~~~ Example references (4 of 4; assessments first): - [doi:10.1007/s11669-017-0572-5](https://doi.org/10.1007/s11669-017-0572-5) Wojciech Gierlotka, Yi-Cheng Tung, A New Thermodynamic Description of the Bi-Pb-Sn System, J. Phase Equilib. Diffus. 38, 814-828 (2017). _assessment that models this phase_ - [doi:10.1016/j.tca.2021.178913](https://doi.org/10.1016/j.tca.2021.178913) Renu Agarwal, Understanding uranium interactions with bismuth and lead-bismuth eutectic: Using calorimetric measurements, Thermochimica Acta 699, 178913 (2021). _assessment that models this phase_ - [doi:10.1016/S0040-6031(98)00237-8](https://doi.org/10.1016/S0040-6031%2898%2900237-8) D. Boa, I. Ansara, Thermochim. Acta, 314, 79-86(1998). _assessment that models this phase_ - [doi:10.1016/S0364-5916(98)00022-4](https://doi.org/10.1016/S0364-5916%2898%2900022-4) S.W. Yoon, H.M. Lee, Calphad, 22, 167-78(1998). _assessment that models this phase_ ## BCC_A2 (Bi–Pb) - Id: `phase:bi-pb:bcc-a2`; status `assigned` - Structure: W · A2 · cI2 · Im-3m (229); type `st:a2-w-ci2`; tier A: standard phase name; confidence high - Stability: not stable in 4 calculated diagram(s) - Literature: 0 values (0 accepted) from 0 papers - Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:bi-pb:bcc-a2) Names (5): _corpus: _corpus:phase:bi-pb:bcc-a2 _tdb: _tdb:BiPb-17Gie.tdb:BCC_A2, tdb:BiPb-21Aga.tdb:BCC_A2, tdb:BiPb-98Boa-LB.tdb:BCC_A2, tdb:BiPb-98Yoo.tdb:BCC_A2 ### TDB models of BCC_A2 (4): PHASE and CONSTITUENT statements as written [BiPb-17Gie.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-17Gie.tdb): BCC_A2, type code %B, sha256 `9ba301ea84eb981a…` ~~~~text 32: PHASE BCC_A2 %B 2 1 3 ! 33: CONST BCC_A2 : BI PB : VA : ! ~~~~ [BiPb-21Aga.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-21Aga.tdb): BCC_A2, type code %B, sha256 `767bd5aeaed33a7b…` ~~~~text 37: PHASE BCC_A2 %B 2 1 3 ! 38: CONST BCC_A2 : BI PB : VA : ! ~~~~ [BiPb-98Boa-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-98Boa-LB.tdb): BCC_A2, type code %B, sha256 `c36b3e9ef4935609…` ~~~~text 34: PHASE BCC_A2 %B 2 1 3 ! 35: CONST BCC_A2 : BI PB : VA : ! ~~~~ [BiPb-98Yoo.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-98Yoo.tdb): BCC_A2, type code %B, sha256 `a29e66212cd9bf01…` ~~~~text 30: PHASE BCC_A2 %B 2 1 3 ! 31: CONST BCC_A2 : BI PB : VA : ! ~~~~ Example references (4 of 4; assessments first): - [doi:10.1007/s11669-017-0572-5](https://doi.org/10.1007/s11669-017-0572-5) Wojciech Gierlotka, Yi-Cheng Tung, A New Thermodynamic Description of the Bi-Pb-Sn System, J. Phase Equilib. Diffus. 38, 814-828 (2017). _assessment that models this phase_ - [doi:10.1016/j.tca.2021.178913](https://doi.org/10.1016/j.tca.2021.178913) Renu Agarwal, Understanding uranium interactions with bismuth and lead-bismuth eutectic: Using calorimetric measurements, Thermochimica Acta 699, 178913 (2021). _assessment that models this phase_ - [doi:10.1016/S0040-6031(98)00237-8](https://doi.org/10.1016/S0040-6031%2898%2900237-8) D. Boa, I. Ansara, Thermochim. Acta, 314, 79-86(1998). _assessment that models this phase_ - [doi:10.1016/S0364-5916(98)00022-4](https://doi.org/10.1016/S0364-5916%2898%2900022-4) S.W. Yoon, H.M. Lee, Calphad, 22, 167-78(1998). _assessment that models this phase_ ## FCC_A1 (Bi–Pb) - Id: `phase:bi-pb: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 4 of 4 calculated diagram(s): 300–2499.36 K, x(Pb) 0.76884–1 - Literature: 0 values (0 accepted) from 0 papers - Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:bi-pb:fcc-a1) Names (5): _corpus: _corpus:phase:bi-pb:fcc-a1 _tdb: _tdb:BiPb-17Gie.tdb:FCC_A1, tdb:BiPb-21Aga.tdb:FCC_A1, tdb:BiPb-98Boa-LB.tdb:FCC_A1, tdb:BiPb-98Yoo.tdb:FCC_A1 ### TDB models of FCC_A1 (4): PHASE and CONSTITUENT statements as written [BiPb-17Gie.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-17Gie.tdb): FCC_A1, type code %A, sha256 `9ba301ea84eb981a…` ~~~~text 27: PHASE FCC_A1 %A 2 1 1 ! 28: CONST FCC_A1 : BI PB : VA : ! ~~~~ [BiPb-21Aga.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-21Aga.tdb): FCC_A1, type code %A, sha256 `767bd5aeaed33a7b…` ~~~~text 32: PHASE FCC_A1 %A 2 1 1 ! 33: CONST FCC_A1 : BI PB : VA : ! ~~~~ [BiPb-98Boa-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-98Boa-LB.tdb): FCC_A1, type code %A, sha256 `c36b3e9ef4935609…` ~~~~text 29: PHASE FCC_A1 %A 2 1 1 ! 30: CONST FCC_A1 : BI PB : VA : ! ~~~~ [BiPb-98Yoo.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-98Yoo.tdb): FCC_A1, type code %A, sha256 `a29e66212cd9bf01…` ~~~~text 25: PHASE FCC_A1 %A 2 1 1 ! 26: CONST FCC_A1 : BI PB : VA : ! ~~~~ Example references (4 of 4; assessments first): - [doi:10.1007/s11669-017-0572-5](https://doi.org/10.1007/s11669-017-0572-5) Wojciech Gierlotka, Yi-Cheng Tung, A New Thermodynamic Description of the Bi-Pb-Sn System, J. Phase Equilib. Diffus. 38, 814-828 (2017). _assessment that models this phase_ - [doi:10.1016/j.tca.2021.178913](https://doi.org/10.1016/j.tca.2021.178913) Renu Agarwal, Understanding uranium interactions with bismuth and lead-bismuth eutectic: Using calorimetric measurements, Thermochimica Acta 699, 178913 (2021). _assessment that models this phase_ - [doi:10.1016/S0040-6031(98)00237-8](https://doi.org/10.1016/S0040-6031%2898%2900237-8) D. Boa, I. Ansara, Thermochim. Acta, 314, 79-86(1998). _assessment that models this phase_ - [doi:10.1016/S0364-5916(98)00022-4](https://doi.org/10.1016/S0364-5916%2898%2900022-4) S.W. Yoon, H.M. Lee, Calphad, 22, 167-78(1998). _assessment that models this phase_ ## HCP_A3 (Bi–Pb) - Id: `phase:bi-pb: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 4 of 4 calculated diagram(s): 300–459.3 K, x(Pb) 0.57133–0.75363 - Literature: 0 values (0 accepted) from 0 papers - Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:bi-pb:hcp-a3) Names (5): _corpus: _corpus:phase:bi-pb:hcp-a3 _tdb: _tdb:BiPb-17Gie.tdb:HCP_A3, tdb:BiPb-21Aga.tdb:HCP_A3, tdb:BiPb-98Boa-LB.tdb:HCP_A3, tdb:BiPb-98Yoo.tdb:HCP_A3 ### TDB models of HCP_A3 (4): PHASE and CONSTITUENT statements as written [BiPb-17Gie.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-17Gie.tdb): HCP_A3, type code %A, sha256 `9ba301ea84eb981a…` ~~~~text 37: PHASE HCP_A3 %A 2 1 0.5 ! 38: CONST HCP_A3 : BI PB : VA: ! ~~~~ [BiPb-21Aga.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-21Aga.tdb): HCP_A3, type code %A, sha256 `767bd5aeaed33a7b…` ~~~~text 42: PHASE HCP_A3 %A 2 1 0.5 ! 43: CONST HCP_A3 : BI PB : VA: ! ~~~~ [BiPb-98Boa-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-98Boa-LB.tdb): HCP_A3, type code %A, sha256 `c36b3e9ef4935609…` ~~~~text 39: PHASE HCP_A3 %A 2 1 0.5 ! 40: CONST HCP_A3 : BI PB : VA: ! ~~~~ [BiPb-98Yoo.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-98Yoo.tdb): HCP_A3, type code %A, sha256 `a29e66212cd9bf01…` ~~~~text 35: PHASE HCP_A3 %A 2 1 0.5 ! 36: CONST HCP_A3 : BI PB : VA: ! ~~~~ Example references (4 of 4; assessments first): - [doi:10.1007/s11669-017-0572-5](https://doi.org/10.1007/s11669-017-0572-5) Wojciech Gierlotka, Yi-Cheng Tung, A New Thermodynamic Description of the Bi-Pb-Sn System, J. Phase Equilib. Diffus. 38, 814-828 (2017). _assessment that models this phase_ - [doi:10.1016/j.tca.2021.178913](https://doi.org/10.1016/j.tca.2021.178913) Renu Agarwal, Understanding uranium interactions with bismuth and lead-bismuth eutectic: Using calorimetric measurements, Thermochimica Acta 699, 178913 (2021). _assessment that models this phase_ - [doi:10.1016/S0040-6031(98)00237-8](https://doi.org/10.1016/S0040-6031%2898%2900237-8) D. Boa, I. Ansara, Thermochim. Acta, 314, 79-86(1998). _assessment that models this phase_ - [doi:10.1016/S0364-5916(98)00022-4](https://doi.org/10.1016/S0364-5916%2898%2900022-4) S.W. Yoon, H.M. Lee, Calphad, 22, 167-78(1998). _assessment that models this phase_ ## LIQUID (Bi–Pb) - Id: `phase:bi-pb:liquid`; status `assigned` - Structure: liquid; type `st:liquid`; liquid; confidence high - Stability: stable in 4 of 4 calculated diagram(s): 398.14–2500 K, x(Pb) 0–1 - Literature: 0 values (0 accepted) from 0 papers - Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:bi-pb:liquid) Names (5): _corpus: _corpus:phase:bi-pb:liquid _tdb: _tdb:BiPb-17Gie.tdb:LIQUID, tdb:BiPb-21Aga.tdb:LIQUID, tdb:BiPb-98Boa-LB.tdb:LIQUID, tdb:BiPb-98Yoo.tdb:LIQUID ### TDB models of LIQUID (4): PHASE and CONSTITUENT statements as written [BiPb-17Gie.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-17Gie.tdb): LIQUID, type code %, sha256 `9ba301ea84eb981a…` ~~~~text 22: PHASE LIQUID:L % 1 1 ! 23: CONST LIQUID:L : BI PB : ! ~~~~ [BiPb-21Aga.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-21Aga.tdb): LIQUID, type code %, sha256 `767bd5aeaed33a7b…` ~~~~text 27: PHASE LIQUID:L % 1 1 ! 28: CONST LIQUID:L : BI PB : ! ~~~~ [BiPb-98Boa-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-98Boa-LB.tdb): LIQUID, type code %, sha256 `c36b3e9ef4935609…` ~~~~text 24: PHASE LIQUID:L % 1 1 ! 25: CONST LIQUID:L : BI PB : ! ~~~~ [BiPb-98Yoo.tdb](https://orchid-project.org/data/databases/sgte-binary/BiPb-98Yoo.tdb): LIQUID, type code %, sha256 `a29e66212cd9bf01…` ~~~~text 20: PHASE LIQUID:L % 1 1 ! 21: CONST LIQUID:L : BI PB : ! ~~~~ Example references (4 of 4; assessments first): - [doi:10.1007/s11669-017-0572-5](https://doi.org/10.1007/s11669-017-0572-5) Wojciech Gierlotka, Yi-Cheng Tung, A New Thermodynamic Description of the Bi-Pb-Sn System, J. Phase Equilib. Diffus. 38, 814-828 (2017). _assessment that models this phase_ - [doi:10.1016/j.tca.2021.178913](https://doi.org/10.1016/j.tca.2021.178913) Renu Agarwal, Understanding uranium interactions with bismuth and lead-bismuth eutectic: Using calorimetric measurements, Thermochimica Acta 699, 178913 (2021). _assessment that models this phase_ - [doi:10.1016/S0040-6031(98)00237-8](https://doi.org/10.1016/S0040-6031%2898%2900237-8) D. Boa, I. Ansara, Thermochim. Acta, 314, 79-86(1998). _assessment that models this phase_ - [doi:10.1016/S0364-5916(98)00022-4](https://doi.org/10.1016/S0364-5916%2898%2900022-4) S.W. Yoon, H.M. Lee, Calphad, 22, 167-78(1998). _assessment that models 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).