# C–Hf–Zr system

> C–Hf–Zr system: 51 accepted literature values (crystal structure 40, invariant reaction 11) and 0 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote.

HTML: https://data.orchid-project.org/systems/C-HF-ZR.html · Markdown: https://data.orchid-project.org/systems/C-HF-ZR.md

51 accepted literature values from 1 paper(s) (experimental 27, model 12, unspecified 12); 0 calculated phase diagram(s). 1 further extracted value(s) not accepted by the reader-agreement checks are only in the JSON/CSV.

Data: [JSON](https://data.orchid-project.org/literature/systems/C-HF-ZR.json) · [CSV](https://data.orchid-project.org/systems/C-HF-ZR.csv) · [interactive explorer](https://orchid-project.org/data-explorer/#C-HF-ZR) · [papers (bibliography)](https://data.orchid-project.org/bibliography/pages/systems/C-HF-ZR.html) · [Markdown](https://data.orchid-project.org/systems/C-HF-ZR.md)

Table: Accepted values by evidence class

| Evidence class | Values |
|---|---:|
| experimental | 27 |
| model | 12 |
| unspecified | 12 |

Table: Accepted values by property group

| Property group | Values |
|---|---:|
| invariant reaction | 11 |
| crystal structure | 40 |

## Invariant reactions (literature)

Table: Invariant reactions reported in the literature for the C–Hf–Zr system (11)

| T (K) | Reaction / phases | Compositions (mole fraction) | Class | Source | Location | Quote |
|---:|---|---|---|---|---|---|
| 4215 | congruent melting: l \<-> HfC1-x | HfC1-x: C 0.4844; l: C 0.4844; 1: C 0.4844; HfC1−x: C 0.4844 | model | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 2, p. 5, row 7; `ORC-4WLYZN74LS` |  |
| 3694 | congruent melting: l \<-> ZrC1-x | ZrC1-x: C 0.4597; l: C 0.4597; 1: C 0.4597; ZrC1−x: C 0.4597 | model | [1] Bittermann 2002; _cites Fernandez 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901310-e) | Table 2, p. 5, row 1; `ORC-U7I37H73YU` |  |
| 3446 | eutectic: l \<-> HfC1-x + C | HfC1-x: C 0.4987; C: C 1; l: C 0.6803; 1: C 0.6803; HfC1−x: C 0.4987 | model | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 2, p. 5, row 8; `ORC-V2ZJHMFLOF` |  |
| 3200 | eutectic: l \<-> ZrC1-x + C | ZrC1-x: C 0.4948; C: C 1; l: C 0.6757; 1: C 0.6757; ZrC1−x: C 0.4948 | model | [1] Bittermann 2002; _cites Fernandez 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901310-e) | Table 2, p. 5, row 2; `ORC-3YTCFE2MUA` |  |
| 2649 | peritectic: l + HfC1-x \<-> (αHf) | HfC1-x: C 0.3348; (αHf): C 0.1398; l: C 0.0602; 1: C 0.0602; HfC1−x: C 0.3348 | model | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 2, p. 5, row 9; `ORC-MUHFT6P7IH` |  |
| 2506 | congruent melting: l \<-> βHf | βHf: C 0; l: C 0; 1: C 0 | model | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 2, p. 5, row 10; `ORC-VHZCUZLZ6U` |  |
| 2480 | eutectic: l \<-> (βHf) + (αHf) | (βHf): C 0.005; (αHf): C 0.0293; l: C 0.0137; 1: C 0.0137 | model | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 2, p. 5, row 11; `ORC-OK244NDQGG` |  |
| 2324 | quasi-peritectic: α(Hf,Zr)(C) + L ↔ β(Hf,Zr)(C) + (Hf,Zr)C1−x | α(Hf,Zr)(C): C 0.0361, Hf 0.7301, Zr 0.2338; L: C 0.017, Hf 0.6426, Zr 0.3404; β(Hf,Zr)(C): C 0.0049, Hf 0.6914, Zr 0.3037; (Hf,Zr)C1−x: C 0.3355, Hf 0.5295, Zr 0.135; (Hf,Zr)C1-x: C 0.3355, Hf 0.5295, Zr 0.135 | model | [1] Bittermann 2002 | Table 3, p. 12, row 1; `ORC-PEUNBYYOPM` |  |
| 2303 | quasi-peritectic: α(Hf,Zr)(C) + L ↔ β(Hf,Zr)(C) + (Hf,Zr)C1−x | α(Hf,Zr)(C): C 0.085, Hf 0.685, Zr 0.23; L: C 0.015, Hf 0.635, Zr 0.35; β(Hf,Zr)(C): C 0.005, Hf 0.64, Zr 0.355; (Hf,Zr)C1−x: C 0.375, Hf 0.535, Zr 0.09; (Hf,Zr)C1-x: C 0.375, Hf 0.535, Zr 0.09 | experimental | [1] Bittermann 2002; _cites ref. 1996Bru_ | Table 3, p. 12, row 2; `ORC-NYGGQMRB4W` |  |
| 2128 | congruent melting: l \<-> βZr | βZr: C 0; l: C 0; 1: C 0 | model | [1] Bittermann 2002; _cites Fernandez 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901310-e) | Table 2, p. 5, row 3; `ORC-R5A76VARIK` |  |
| 2127 | eutectic: l \<-> (βZr) + ZrC1-x | (βZr): C 0.0053; ZrC1-x: C 0.3591; l: C 0.006; 1: C 0.006; ZrC1−x: C 0.3591 | model | [1] Bittermann 2002; _cites Fernandez 1995_ [doi](https://doi.org/10.1016/0925-8388%2894%2901310-e) | Table 2, p. 5, row 4; `ORC-WFTQ46XZZZ` |  |

## Other properties

### Crystal structure (40)

Table: Crystal structure, C–Hf–Zr system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Lattice a | 4.647 Å | 298.15 | (HfyZr1-y)C1-x; _alloy: Hf 0.274725, Zr 0.274725_ | unspecified | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 1, p. 5, row 4; `ORC-ABGOYDTRDS.949cce` |  |
| Lattice a | 4.668 Å | 298.15 | (HfyZr1-y)C1-x; _alloy: Hf 0.26738, Zr 0.26738_ | unspecified | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 1, p. 5, row 5; `ORC-CROCIW6V3J.929ffb` |  |
| Lattice a | 4.652 Å | 298.15 | (HfyZr1-y)C1-x; _alloy: Hf 0.408163, Zr 0.102041_ | unspecified | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 1, p. 5, row 3; `ORC-GICM5F7HFK.24646e` |  |
| Lattice a | 4.684 Å | 298.15 | (HfyZr1-y)C1-x; _alloy: Hf 0.10989, Zr 0.43956_ | unspecified | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 1, p. 5, row 7; `ORC-LBAHNSUMZO.6b6e8c` |  |
| Lattice a | 4.651 Å | 298.15 | (HfyZr1-y)C1-x; _alloy: Hf 0.427807, Zr 0.106952_ | unspecified | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 1, p. 5, row 2; `ORC-LDI6KCCMTS.6bc2bf` |  |
| Lattice a | 4.67 Å | 298.15 | (HfyZr1-y)C1-x; _alloy: Hf 0.255102, Zr 0.255102_ | unspecified | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 1, p. 5, row 6; `ORC-S46N4VCYTL.4c64bb` |  |
| Lattice a | 4.689 Å | 298.15 | (HfyZr1-y)C1-x; _alloy: Hf 0.106952, Zr 0.427807_ | unspecified | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 1, p. 5, row 8; `ORC-TIG6P6XRTJ.4fb15b` |  |
| Lattice a | 4.691 Å | 298.15 | (HfyZr1-y)C1-x; _alloy: Hf 0.102041, Zr 0.408163_ | unspecified | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 1, p. 5, row 9; `ORC-VOPGPN4EBC.9172ef` |  |
| Lattice a | 4.647 Å | 298.15 | (HfyZr1-y)C1-x; _alloy: Hf 0.43956, Zr 0.10989_ | unspecified | [1] Bittermann 2002; _cites Bittermann 2002_ | Table 1, p. 5, row 1; `ORC-XI3KUE75OX.0bd1e4` |  |
| Lattice a | 3.231 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.052_ | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 4, row 4; `ORC-3IGNYESDET.201269` |  |
| Lattice a | 3.209 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.429_ | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 4, row 6; `ORC-4KHKIMJEFV.bf371f` |  |
| Lattice a | 3.202 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.713_ | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 4, row 7; `ORC-DSPZ3CGHO7.87c0bb` |  |
| Lattice a | 3.219 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.211_ | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 4, row 5; `ORC-DV3PZWDRUG.97f216` |  |
| Lattice a | 3.211 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.618_ | experimental | [1] Bittermann 2002; _cites Russell 1953_ [doi](https://doi.org/10.1063/1.1721254) | Table 1, p. 4, row 11; `ORC-FWUSRWEVXY.b65fe1` |  |
| Lattice a | 3.199 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.965_ | experimental | [1] Bittermann 2002; _cites Russell 1953_ [doi](https://doi.org/10.1063/1.1721254) | Table 1, p. 4, row 12; `ORC-MOKBI7D6VI.a2b975` |  |
| Lattice a | 3.231 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.012_ | experimental | [1] Bittermann 2002; _cites Russell 1953_ [doi](https://doi.org/10.1063/1.1721254) | Table 1, p. 4, row 10; `ORC-NS6HH4YZFR.7a79fa` |  |
| Lattice a | 3.231 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0_ | experimental | [1] Bittermann 2002; _cites Russell 1953_ [doi](https://doi.org/10.1063/1.1721254) | Table 1, p. 4, row 9; `ORC-U6FHQIMDAM.9669e2` |  |
| Lattice a | 3.226 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0_ | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 4, row 3; `ORC-YXYBIPI3ST.eb84eb` |  |
| Lattice a | 5.008 Å | 298.15 | ω(HfxZr1−x) | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 5, row 12; `ORC-DT2PCWEDT5.4f02bf` |  |
| Lattice a | 5.021 Å | 298.15 | ω(HfxZr1−x) | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 5, row 11; `ORC-QWBMQ4JIVU.30882a` |  |
| Lattice a | 5.035 Å | 298.15 | ω(HfxZr1−x); _alloy: Hf 0_ | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 5, row 10; `ORC-UOQDHILTJN.042e38` |  |
| Lattice a | 4.991 Å | 298.15 | ω(HfxZr1−x) | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 5, row 13; `ORC-YP7IYGCY77.037f3d` |  |
| Lattice a | 4.691 Å | 3427 (\<) | ZrC1-x; _ZrC1-x: C 0.35_ | unspecified | [1] Bittermann 2002; _cites Storms 1967_ | Table 1, p. 4, row 18; `ORC-66QMJXOLCU` |  |
| Lattice a | 4.7017 Å | 3540 (\<) | ZrC1-x; _ZrC1-x: C 0.46_ | unspecified | [1] Bittermann 2002; _cites Storms 1967_ | Table 1, p. 4, row 17; `ORC-YSTXZ5VBDV` |  |
| Lattice a | 2.4612 Å | 3827 (\<) | (C); _alloy: Hf 0, Zr 0_ | model | [1] Bittermann 2002; _cites Massalski 1990_ | Table 1, p. 4, row 16; `ORC-DQC7TTSVJI.005471` |  |
| Lattice a | 4.606 Å | 3950 (\<) | HfC1-x; _HfC1-x: C 0.34_ | unspecified | [1] Bittermann 2002; _cites ref. 1969Rud_ | Table 1, p. 4, row 20; `ORC-UDMMRKUNXX` |  |
| Lattice c | 5.134 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.052_ | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 4, row 4; `ORC-3IGNYESDET.c89e75` |  |
| Lattice c | 5.126 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.429_ | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 4, row 6; `ORC-4KHKIMJEFV.d1e198` |  |
| Lattice c | 5.106 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.713_ | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 4, row 7; `ORC-DSPZ3CGHO7.4010fd` |  |
| Lattice c | 5.115 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.211_ | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 4, row 5; `ORC-DV3PZWDRUG.435c89` |  |
| Lattice c | 5.098 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.618_ | experimental | [1] Bittermann 2002; _cites Russell 1953_ [doi](https://doi.org/10.1063/1.1721254) | Table 1, p. 4, row 11; `ORC-FWUSRWEVXY.c37e09` |  |
| Lattice c | 5.066 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.965_ | experimental | [1] Bittermann 2002; _cites Russell 1953_ [doi](https://doi.org/10.1063/1.1721254) | Table 1, p. 4, row 12; `ORC-MOKBI7D6VI.831c72` |  |
| Lattice c | 5.146 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0.012_ | experimental | [1] Bittermann 2002; _cites Russell 1953_ [doi](https://doi.org/10.1063/1.1721254) | Table 1, p. 4, row 10; `ORC-NS6HH4YZFR.9cd0ef` |  |
| Lattice c | 5.148 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0_ | experimental | [1] Bittermann 2002; _cites Russell 1953_ [doi](https://doi.org/10.1063/1.1721254) | Table 1, p. 4, row 9; `ORC-U6FHQIMDAM.023509` |  |
| Lattice c | 5.146 Å | 298.15 | α(HfxZr1-x); _α(HfxZr1-x): Hf 0_ | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 4, row 3; `ORC-YXYBIPI3ST.37ed41` |  |
| Lattice c | 3.107 Å | 298.15 | ω(HfxZr1−x) | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 5, row 12; `ORC-DT2PCWEDT5.25d7cc` |  |
| Lattice c | 3.119 Å | 298.15 | ω(HfxZr1−x) | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 5, row 11; `ORC-QWBMQ4JIVU.466c8e` |  |
| Lattice c | 3.141 Å | 298.15 | ω(HfxZr1−x); _alloy: Hf 0_ | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 5, row 10; `ORC-UOQDHILTJN.685436` |  |
| Lattice c | 3.093 Å | 298.15 | ω(HfxZr1−x) | experimental | [1] Bittermann 2002; _cites Ming 1981_ [doi](https://doi.org/10.1063/1.329760) | Table 1, p. 5, row 13; `ORC-YP7IYGCY77.b90ca0` |  |
| Lattice c | 6.709 Å | 3827 (\<) | (C); _alloy: Hf 0, Zr 0_ | model | [1] Bittermann 2002; _cites Massalski 1990_ | Table 1, p. 4, row 16; `ORC-DQC7TTSVJI.f68c63` |  |

## Sources

Reporting papers the values were read from (a value cited from another work names that work in its row).

1. H. Bittermann, P. Rogl, Critical assessment and thermodynamic calculation of the ternary system C-Hf-Zr (Carbon-Zirconium-Hafnium), JPE 23, 218-235 (2002). [doi:10.1361/105497102770331703](https://doi.org/10.1361/105497102770331703)

## Please cite

- R. Arróyave, J. Saal, D. Shin, ORCHID-Values: thermodynamic and phase-equilibrium values read from the literature (version 2026.10; Version 1, machine-extracted), Zenodo (2026). https://doi.org/10.5281/zenodo.23735569
- 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 the original source of every value you use (paper_citation / paper_doi, and cited_dois for values the paper cites from earlier work); 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).

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_literature_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Values: thermodynamic and phase-equilibrium values read from the literature}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735569},
  url       = {https://doi.org/10.5281/zenodo.23735569},
  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 ORCHID ([CITATION.cff](https://data.orchid-project.org/CITATION.cff)) and the original sources. Quotes are short excerpts kept so that each value can be checked; they remain under the publishers' copyright and are not relicensed. Source papers, page images and full text are not redistributed. Field reference: [SCHEMA.md](https://data.orchid-project.org/literature/SCHEMA.md). Machine-readable guide: [llms.txt](https://data.orchid-project.org/llms.txt). Found an error? The report link of a value (Markdown: its id, ORC-..., in the Location column) opens a pre-filled GitHub issue, https://github.com/orchid-calphad/orchid-data/issues/new?template=report-value-error.yml&record_id=\<id>, carrying only the record id, source and value; [how to contribute](https://orchid-project.org/contribute/).