# C–Y phases

> C–Y system: 13 phases (tier A 9, tier C 1, liquid 1, needs_review 2); 11 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/C-Y.html · Markdown: https://data.orchid-project.org/phases/pages/C-Y.md

13 phases (tier A 9, tier C 1, 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](https://orchid-project.org/phases/?q=C-Y) · [full JSON](https://data.orchid-project.org/phases/systems/C-Y.json) · [C–Y system page](https://data.orchid-project.org/systems/C-Y.html) · [Markdown](https://data.orchid-project.org/phases/pages/C-Y.md) · [field reference](https://data.orchid-project.org/phases/SCHEMA.md)

Table: Phases of the C–Y system (13)

| Phase | Structure | Basis | Stability (calculated) | Literature values | TDB models |
|---|---|---|---|---:|---:|
| [DIAMOND_A4](#phase-c-y-a4-diamond); _phase:c-y:a4-diamond_ | C (diamond) · A4 · cF8 · Fd-3m (227) | tier A: standard phase name | not stable in 2 calculated diagram(s) | 0 | 2 |
| [GRAPHITE_A9](#phase-c-y-a9-graphite); _phase:c-y:a9-graphite_ | C (graphite) · A9 · hP4 · P6_3/mmc (194) | tier A: standard phase name | stable in 1 of 1 calculated diagram(s): 300–4000 K, x(C) 1–1 | 0 | 1 |
| [BCC_A2](#phase-c-y-bcc-a2); _phase:c-y:bcc-a2_ | W · A2 · cI2 · Im-3m (229) | tier A: standard phase name | stable in 2 of 2 calculated diagram(s): 1759.19–1860 K, x(C) 0–0.0645 | 0 | 2 |
| [FCC_A1](#phase-c-y-fcc-a1); _phase:c-y:fcc-a1_ | Cu · A1 · cF4 · Fm-3m (225) | tier A: standard phase name | not stable in 2 calculated diagram(s) | 0 | 2 |
| [GRAPHITE](#phase-c-y-graphite); _phase:c-y:graphite_ | C (graphite) · A9 · hP4 · P6_3/mmc (194) | tier A: standard phase name | stable in 1 of 1 calculated diagram(s): 300–4000 K, x(C) 1–1 | 0 | 1 |
| [HCP_A3](#phase-c-y-hcp-a3); _phase:c-y:hcp-a3_ | Mg · A3 · hP2 · P6_3/mmc (194) | tier A: standard phase name | stable in 2 of 2 calculated diagram(s): 300–1863.42 K, x(C) 0–0.06942 | 0 | 2 |
| [LIQUID](#phase-c-y-liquid); _phase:c-y:liquid_ | liquid | liquid | stable in 2 of 2 calculated diagram(s): 1783.77–4000 K, x(C) 0–0.86706 | 0 | 2 |
| [Y15C19_ALPHA](#phase-c-y-y15c19-alpha); _phase:c-y:y15c19-alpha_ | alpha-Y15C19 · oP18 · Pbam (55) | tier C: assessor-stated (Hallstedt 2025 crystallographic table) | stable in 2 of 2 calculated diagram(s): 300–1577.78 K, x(C) 0.54024–0.55882 | 0 | 2 |
| [Y15C19_BETA](#phase-c-y-y15c19-beta); _phase:c-y:y15c19-beta_ |  | needs_review | stable in 2 of 2 calculated diagram(s): 1577–1802.7 K, x(C) 0.55247–0.55882 | 0 | 2 |
| [Y2C3_BETA](#phase-c-y-y2c3-beta); _phase:c-y:y2c3-beta_ |  | needs_review | stable in 2 of 2 calculated diagram(s): 1419.06–1939.61 K, x(C) 0.5625–0.59934 | 0 | 2 |
| [Y2C3_D5C](#phase-c-y-y2c3-d5c); _phase:c-y:y2c3-d5c_ | Pu2C3 · D5_c · cI40 · I-43d (220) | tier A: standard phase name | stable in 2 of 2 calculated diagram(s): 300–1458.9 K, x(C) 0.56893–0.6 | 0 | 2 |
| [YC_B1](#phase-c-y-yc-b1); _phase:c-y:yc-b1_ | NaCl · B1 · cF8 · Fm-3m (225) | tier A: standard phase name | stable in 2 of 2 calculated diagram(s): 362.2–2671.34 K, x(C) 0.17039–0.66533 | 6 | 2 |
| [YC2_C11A](#phase-c-y-yc2-c11a); _phase:c-y:yc2-c11a_ | CaC2 · C11_a · tI6 · I4/mmm (139) | tier A: standard phase name | stable in 2 of 2 calculated diagram(s): 300–1614.54 K, x(C) 0.66667–0.66667 | 0 | 2 |

## DIAMOND_A4 (C–Y)

- Id: `phase:c-y:a4-diamond`; status `assigned`
- Structure: C (diamond) · A4 · cF8 · Fd-3m (227); type `st:a4-c-diamond-cf8`; tier A: standard phase name; confidence high
- Stoichiometry: C 1.0000
- Stability: not stable in 2 calculated diagram(s)
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:c-y:a4-diamond)

Names (3): _corpus: _corpus:phase:c-y:a4-diamond  
_tdb: _tdb:YC-19Xu.tdb:DIAMOND_A4, tdb:YC-95Gro-LB.tdb:DIAMOND_A4  


### TDB models of DIAMOND_A4 (2): PHASE and CONSTITUENT statements as written

[YC-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-19Xu.tdb): DIAMOND_A4, type code %, sha256 `12bad06794b6d2f9…`

~~~~text
48: PHASE DIAMOND_A4 % 1 1 !
49: CONST DIAMOND_A4 : C : !
~~~~

[YC-95Gro-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-95Gro-LB.tdb): DIAMOND_A4, type code %, sha256 `4de222c3b8683308…`

~~~~text
56: PHASE DIAMOND_A4 % 1 1 !
57: CONST DIAMOND_A4 : C : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/0925-8388(94)06028-2](https://doi.org/10.1016/0925-8388%2894%2906028-2) J. Gröbner, H.-L. Lukas, F. Aldinger, Thermodynamic calculations in the YAlC system, Journal of Alloys and Compounds 220, 8-14 (1995).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## GRAPHITE_A9 (C–Y)

- Id: `phase:c-y:a9-graphite`; status `assigned`
- Structure: C (graphite) · A9 · hP4 · P6_3/mmc (194); type `st:a9-c-graphite-hp4`; tier A: standard phase name; confidence high
- Stoichiometry: C 1.0000
- Stability: stable in 1 of 1 calculated diagram(s): 300–4000 K, x(C) 1–1
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:c-y:a9-graphite)

Names (2): _corpus: _corpus:phase:c-y:a9-graphite  
_tdb: _tdb:YC-95Gro-LB.tdb:GRAPHITE_A9  


### TDB models of GRAPHITE_A9 (1): PHASE and CONSTITUENT statements as written

[YC-95Gro-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-95Gro-LB.tdb): GRAPHITE_A9, type code %, sha256 `4de222c3b8683308…`

~~~~text
61: PHASE GRAPHITE_A9 % 1 1 !
62: CONST GRAPHITE_A9 : C : !
~~~~

Example references (1 of 1; assessments first): 

- [doi:10.1016/0925-8388(94)06028-2](https://doi.org/10.1016/0925-8388%2894%2906028-2) J. Gröbner, H.-L. Lukas, F. Aldinger, Thermodynamic calculations in the YAlC system, Journal of Alloys and Compounds 220, 8-14 (1995).  
_assessment that models this phase_

## BCC_A2 (C–Y)

- Id: `phase:c-y: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): 1759.19–1860 K, x(C) 0–0.0645
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:c-y:bcc-a2)

Names (3): _corpus: _corpus:phase:c-y:bcc-a2  
_tdb: _tdb:YC-19Xu.tdb:BCC_A2, tdb:YC-95Gro-LB.tdb:BCC_A2  


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

[YC-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-19Xu.tdb): BCC_A2, type code %B, sha256 `12bad06794b6d2f9…`

~~~~text
38: PHASE BCC_A2 %B 2 1 3 !
39: CONST BCC_A2 : Y : C VA% : !
~~~~

[YC-95Gro-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-95Gro-LB.tdb): BCC_A2, type code %B, sha256 `4de222c3b8683308…`

~~~~text
46: PHASE BCC_A2 %B 2 1 3 !
47: CONST BCC_A2 : Y : C VA% : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/0925-8388(94)06028-2](https://doi.org/10.1016/0925-8388%2894%2906028-2) J. Gröbner, H.-L. Lukas, F. Aldinger, Thermodynamic calculations in the YAlC system, Journal of Alloys and Compounds 220, 8-14 (1995).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## FCC_A1 (C–Y)

- Id: `phase:c-y: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](https://orchid-project.org/phases/#phase:c-y:fcc-a1)

Names (3): _corpus: _corpus:phase:c-y:fcc-a1  
_tdb: _tdb:YC-19Xu.tdb:FCC_A1, tdb:YC-95Gro-LB.tdb:FCC_A1  


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

[YC-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-19Xu.tdb): FCC_A1, type code %A, sha256 `12bad06794b6d2f9…`

~~~~text
33: PHASE FCC_A1 %A 2 1 1 !
34: CONST FCC_A1 : Y : C% VA : !
~~~~

[YC-95Gro-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-95Gro-LB.tdb): FCC_A1, type code %A, sha256 `4de222c3b8683308…`

~~~~text
41: PHASE FCC_A1 %A 2 1 1 !
42: CONST FCC_A1 : Y : C% VA : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/0925-8388(94)06028-2](https://doi.org/10.1016/0925-8388%2894%2906028-2) J. Gröbner, H.-L. Lukas, F. Aldinger, Thermodynamic calculations in the YAlC system, Journal of Alloys and Compounds 220, 8-14 (1995).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## GRAPHITE (C–Y)

- Id: `phase:c-y:graphite`; status `assigned`
- Structure: C (graphite) · A9 · hP4 · P6_3/mmc (194); type `st:a9-c-graphite-hp4`; tier A: standard phase name; confidence high
- Stoichiometry: C 1.0000
- Stability: stable in 1 of 1 calculated diagram(s): 300–4000 K, x(C) 1–1
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:c-y:graphite)

Names (2): _corpus: _corpus:phase:c-y:graphite  
_tdb: _tdb:YC-19Xu.tdb:GRAPHITE  


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

[YC-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-19Xu.tdb): GRAPHITE, type code %, sha256 `12bad06794b6d2f9…`

~~~~text
53: PHASE GRAPHITE % 1 1 !
54: CONST GRAPHITE : C : !
~~~~

Example references (1 of 1; assessments first): 

- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## HCP_A3 (C–Y)

- Id: `phase:c-y: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 2 of 2 calculated diagram(s): 300–1863.42 K, x(C) 0–0.06942
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:c-y:hcp-a3)

Names (3): _corpus: _corpus:phase:c-y:hcp-a3  
_tdb: _tdb:YC-19Xu.tdb:HCP_A3, tdb:YC-95Gro-LB.tdb:HCP_A3  


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

[YC-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-19Xu.tdb): HCP_A3, type code %A, sha256 `12bad06794b6d2f9…`

~~~~text
43: PHASE HCP_A3 %A 2 1 0.5 !
44: CONST HCP_A3 : Y : C VA% : !
~~~~

[YC-95Gro-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-95Gro-LB.tdb): HCP_A3, type code %A, sha256 `4de222c3b8683308…`

~~~~text
51: PHASE HCP_A3 %A 2 1 0.5 !
52: CONST HCP_A3 : Y : C VA% : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/0925-8388(94)06028-2](https://doi.org/10.1016/0925-8388%2894%2906028-2) J. Gröbner, H.-L. Lukas, F. Aldinger, Thermodynamic calculations in the YAlC system, Journal of Alloys and Compounds 220, 8-14 (1995).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## LIQUID (C–Y)

- Id: `phase:c-y:liquid`; status `assigned`
- Structure: liquid; type `st:liquid`; liquid; confidence high
- Stability: stable in 2 of 2 calculated diagram(s): 1783.77–4000 K, x(C) 0–0.86706
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:c-y:liquid)

Names (3): _corpus: _corpus:phase:c-y:liquid  
_tdb: _tdb:YC-19Xu.tdb:LIQUID, tdb:YC-95Gro-LB.tdb:LIQUID  


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

[YC-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-19Xu.tdb): LIQUID, type code %, sha256 `12bad06794b6d2f9…`

~~~~text
28: PHASE LIQUID:L % 1 1 !
29: CONST LIQUID:L : C Y : !
~~~~

[YC-95Gro-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-95Gro-LB.tdb): LIQUID, type code %, sha256 `4de222c3b8683308…`

~~~~text
36: PHASE LIQUID:L % 1 1 !
37: CONST LIQUID:L : C Y : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/0925-8388(94)06028-2](https://doi.org/10.1016/0925-8388%2894%2906028-2) J. Gröbner, H.-L. Lukas, F. Aldinger, Thermodynamic calculations in the YAlC system, Journal of Alloys and Compounds 220, 8-14 (1995).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## Y15C19_ALPHA (C–Y)

- Id: `phase:c-y:y15c19-alpha`; status `assigned`
- Structure: alpha-Y15C19 · oP18 · Pbam (55); type `st:alpha-y15c19-op18`; 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 as stated in the SGTE crystallographic table for this phase name and system
- Stability: stable in 2 of 2 calculated diagram(s): 300–1577.78 K, x(C) 0.54024–0.55882
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:c-y:y15c19-alpha)

Names (3): _corpus: _corpus:phase:c-y:y15c19-alpha  
_tdb: _tdb:YC-19Xu.tdb:Y15C19_ALPHA, tdb:YC-95Gro-LB.tdb:Y15C19_ALPHA  


### TDB models of Y15C19_ALPHA (2): PHASE and CONSTITUENT statements as written

[YC-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-19Xu.tdb): Y15C19_ALPHA, type code %, sha256 `12bad06794b6d2f9…`

~~~~text
63: PHASE Y15C19_ALPHA % 2 15 19 !
64: CONST Y15C19_ALPHA : Y : C% VA : !
~~~~

[YC-95Gro-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-95Gro-LB.tdb): Y15C19_ALPHA, type code %, sha256 `4de222c3b8683308…`

~~~~text
71: PHASE Y15C19_ALPHA % 2 15 19 !
72: CONST Y15C19_ALPHA : Y : C : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/0925-8388(94)06028-2](https://doi.org/10.1016/0925-8388%2894%2906028-2) J. Gröbner, H.-L. Lukas, F. Aldinger, Thermodynamic calculations in the YAlC system, Journal of Alloys and Compounds 220, 8-14 (1995).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## Y15C19_BETA (C–Y)

- Id: `phase:c-y:y15c19-beta`; status `needs_review`
- No structure assigned. Why: no_structure_token; off_stoichiometric_model; sgte_mmc2_row_incomplete
- Candidate (sgte_mmc2): (beta-Y15C19) — Hallstedt 2025 mmc2 row for Y15C19_BETA: beta-Y15C19
- Stability: stable in 2 of 2 calculated diagram(s): 1577–1802.7 K, x(C) 0.55247–0.55882
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:c-y:y15c19-beta)

Names (3): _corpus: _corpus:phase:c-y:y15c19-beta  
_tdb: _tdb:YC-19Xu.tdb:Y15C19_BETA, tdb:YC-95Gro-LB.tdb:Y15C19_BETA  


### TDB models of Y15C19_BETA (2): PHASE and CONSTITUENT statements as written

[YC-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-19Xu.tdb): Y15C19_BETA, type code %, sha256 `12bad06794b6d2f9…`

~~~~text
68: PHASE Y15C19_BETA % 2 15 19 !
69: CONST Y15C19_BETA : Y : C% VA : !
~~~~

[YC-95Gro-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-95Gro-LB.tdb): Y15C19_BETA, type code %, sha256 `4de222c3b8683308…`

~~~~text
76: PHASE Y15C19_BETA % 2 15 19 !
77: CONST Y15C19_BETA : Y : C : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/0925-8388(94)06028-2](https://doi.org/10.1016/0925-8388%2894%2906028-2) J. Gröbner, H.-L. Lukas, F. Aldinger, Thermodynamic calculations in the YAlC system, Journal of Alloys and Compounds 220, 8-14 (1995).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## Y2C3_BETA (C–Y)

- Id: `phase:c-y:y2c3-beta`; status `needs_review`
- No structure assigned. Why: no_structure_token; off_stoichiometric_model; sgte_mmc2_row_incomplete
- Candidate (sgte_mmc2): (beta-Y2C3) — Hallstedt 2025 mmc2 row for Y2C3_BETA: beta-Y2C3
- Stability: stable in 2 of 2 calculated diagram(s): 1419.06–1939.61 K, x(C) 0.5625–0.59934
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:c-y:y2c3-beta)

Names (3): _corpus: _corpus:phase:c-y:y2c3-beta  
_tdb: _tdb:YC-19Xu.tdb:Y2C3_BETA, tdb:YC-95Gro-LB.tdb:Y2C3_BETA  


### TDB models of Y2C3_BETA (2): PHASE and CONSTITUENT statements as written

[YC-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-19Xu.tdb): Y2C3_BETA, type code %, sha256 `12bad06794b6d2f9…`

~~~~text
78: PHASE Y2C3_BETA % 3 2 2 1 !
79: CONST Y2C3_BETA : Y% VA : C : C% VA : !
~~~~

[YC-95Gro-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-95Gro-LB.tdb): Y2C3_BETA, type code %, sha256 `4de222c3b8683308…`

~~~~text
86: PHASE Y2C3_BETA % 3 2 2 1 !
87: CONST Y2C3_BETA : Y : C : C VA : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/0925-8388(94)06028-2](https://doi.org/10.1016/0925-8388%2894%2906028-2) J. Gröbner, H.-L. Lukas, F. Aldinger, Thermodynamic calculations in the YAlC system, Journal of Alloys and Compounds 220, 8-14 (1995).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## Y2C3_D5C (C–Y)

- Id: `phase:c-y:y2c3-d5c`; status `assigned`
- Structure: Pu2C3 · D5_c · cI40 · I-43d (220); type `st:d5-c-pu2c3-ci40`; tier A: standard phase name; confidence high
- Stability: stable in 2 of 2 calculated diagram(s): 300–1458.9 K, x(C) 0.56893–0.6
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:c-y:y2c3-d5c)

Names (3): _corpus: _corpus:phase:c-y:y2c3-d5c  
_tdb: _tdb:YC-19Xu.tdb:Y2C3_D5C, tdb:YC-95Gro-LB.tdb:Y2C3_D5C  


### TDB models of Y2C3_D5C (2): PHASE and CONSTITUENT statements as written

[YC-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-19Xu.tdb): Y2C3_D5C, type code %, sha256 `12bad06794b6d2f9…`

~~~~text
73: PHASE Y2C3_D5C % 3 2 2 1 !
74: CONST Y2C3_D5C : Y% VA : C : C% VA : !
~~~~

[YC-95Gro-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-95Gro-LB.tdb): Y2C3_D5C, type code %, sha256 `4de222c3b8683308…`

~~~~text
81: PHASE Y2C3_D5C % 3 2 2 1 !
82: CONST Y2C3_D5C : Y : C : C VA : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/0925-8388(94)06028-2](https://doi.org/10.1016/0925-8388%2894%2906028-2) J. Gröbner, H.-L. Lukas, F. Aldinger, Thermodynamic calculations in the YAlC system, Journal of Alloys and Compounds 220, 8-14 (1995).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_

## YC_B1 (C–Y)

- Id: `phase:c-y:yc-b1`; status `assigned`
- Structure: NaCl · B1 · cF8 · Fm-3m (225); type `st:b1-nacl-cf8`; tier A: standard phase name; confidence high
- Stability: stable in 2 of 2 calculated diagram(s): 362.2–2671.34 K, x(C) 0.17039–0.66533
- Literature: 6 values (6 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:c-y:yc-b1)

Names (4): _corpus: _corpus:phase:c-y:yc-b1  
_paper: _paper:10.1016/0925-8388(94)06028-2:γ  
_tdb: _tdb:YC-19Xu.tdb:YC_B1, tdb:YC-95Gro-LB.tdb:YC_B1  


### TDB models of YC_B1 (2): PHASE and CONSTITUENT statements as written

[YC-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-19Xu.tdb): YC_B1, type code %, sha256 `12bad06794b6d2f9…`

~~~~text
58: PHASE YC_B1 % 2 1 1 !
59: CONST YC_B1 : Y : C C2 VA : !
~~~~

[YC-95Gro-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-95Gro-LB.tdb): YC_B1, type code %, sha256 `4de222c3b8683308…`

~~~~text
66: PHASE YC_B1 % 2 1 1 !
67: CONST YC_B1 : Y : C C2 VA : !
~~~~

Example references (5 of 5; assessments first): 

- [doi:10.1016/0925-8388(94)06028-2](https://doi.org/10.1016/0925-8388%2894%2906028-2) J. Gröbner, H.-L. Lukas, F. Aldinger, Thermodynamic calculations in the YAlC system, Journal of Alloys and Compounds 220, 8-14 (1995).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_assessment that models this phase_
- [doi:10.1016/0925-8388(94)90783-8](https://doi.org/10.1016/0925-8388%2894%2990783-8) S.V. Meschel, O.J. Kleppa, Standard enthalpies of formation of some rare earth carbides by direct synthesis calorimetry, Journal of Alloys and Compounds 205, 165-168 (1994).  
_cited as the source of values for this phase_
- [doi:10.1063/1.1672942](https://doi.org/10.1063/1.1672942) Fred J. Kohl, Carl A. Stearns, Vaporization Thermodynamics of Yttrium Dicarbide–Carbon System and Dissociation Energy of Yttrium Dicarbide and Tetracarbide, The Journal of Chemical Physics 52, 6310-6315 (1970).  
_cited as the source of values for this phase_
- [doi:10.1063/1.1696715](https://doi.org/10.1063/1.1696715) G. De Maria, M. Guido, L. Malaspina, B. Pesce, Mass-Spectrometric Study of the Yttrium—Carbon System, The Journal of Chemical Physics 43, 4449-4452 (1965).  
_cited as the source of values for this phase_

## YC2_C11A (C–Y)

- Id: `phase:c-y:yc2-c11a`; status `assigned`
- Structure: CaC2 · C11_a · tI6 · I4/mmm (139); type `st:c11-a-cac2-ti6`; tier A: standard phase name; confidence high
- Stoichiometry: C 0.6667, Y 0.3333
- Stability: stable in 2 of 2 calculated diagram(s): 300–1614.54 K, x(C) 0.66667–0.66667
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:c-y:yc2-c11a)

Names (3): _corpus: _corpus:phase:c-y:yc2-c11a  
_tdb: _tdb:YC-19Xu.tdb:YC2_C11A, tdb:YC-95Gro-LB.tdb:YC2_C11A  


### TDB models of YC2_C11A (2): PHASE and CONSTITUENT statements as written

[YC-19Xu.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-19Xu.tdb): YC2_C11A, type code %, sha256 `12bad06794b6d2f9…`

~~~~text
83: PHASE YC2_C11A % 2 1 2 !
84: CONST YC2_C11A : Y : C : !
~~~~

[YC-95Gro-LB.tdb](https://orchid-project.org/data/databases/sgte-binary/YC-95Gro-LB.tdb): YC2_C11A, type code %, sha256 `4de222c3b8683308…`

~~~~text
91: PHASE YC2_C11A % 2 1 2 !
92: CONST YC2_C11A : Y : C : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/0925-8388(94)06028-2](https://doi.org/10.1016/0925-8388%2894%2906028-2) J. Gröbner, H.-L. Lukas, F. Aldinger, Thermodynamic calculations in the YAlC system, Journal of Alloys and Compounds 220, 8-14 (1995).  
_assessment that models this phase_
- [doi:10.1016/j.jeurceramsoc.2019.07.012](https://doi.org/10.1016/j.jeurceramsoc.2019.07.012) Kai Xu, Houke Zou, Keke Chang, Zixuan Deng, Xiaobing Zhou, Yeyan Huang et al., Thermodynamic description of the sintering aid system in silicon carbide ceramics with the addition of yttrium, Journal of the European Ceramic Society 39, 4510-4519 (2019).  
_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).