# O–U–Zr system

> O–U–Zr system: 42 accepted literature values (phase transition 41, phase equilibrium 1) and 0 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote.

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

42 accepted literature values from 3 paper(s) (experimental 24, model 18); 0 calculated phase diagram(s).

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

Table: Accepted values by evidence class

| Evidence class | Values |
|---|---:|
| experimental | 24 |
| model | 18 |

Table: Accepted values by property group

| Property group | Values |
|---|---:|
| phase transition | 41 |
| phase equilibrium | 1 |

## Other properties

### Phase transition (41)

Table: Phase transition, O–U–Zr system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Phase transition | 2470 K | 2470 | other: (U0.65Zr0.35)O2.098 | model | [1] Barrachin 2008 | Table 5, p. 7, row 12; `ORC-XPLW3Z3X4S` |  |
| Phase transition | 2472 K | 2472 | other: N° 8 (BWR, 30% ox.); _alloy: O 0.53974, U 0.18797, Zr 0.27229_ | experimental | [2] Chevalier 2004; _cites Farmer 1999_ | Table 5, p. 25, row 7; `ORC-5S5IM6NSXZ` |  |
| Phase transition | 2498 K | 2498 | other: N° 8 (BWR, 30% ox.); _alloy: O 0.53974, U 0.18797, Zr 0.27229_ | model | [2] Chevalier 2004 | Table 5, p. 25, row 8; `ORC-SBEPMUIHWC` |  |
| Phase transition | 2598 K | 2598 | other: N° 7 (BWR, 50% ox.); _alloy: O 0.58438, U 0.16977, Zr 0.24585_ | model | [2] Chevalier 2004 | Table 5, p. 25, row 10; `ORC-CL6ZNAEOLV` |  |
| Phase transition | 2603 K | 2603 | other: N° 7 (BWR, 50% ox.); _alloy: O 0.58438, U 0.16977, Zr 0.24585_ | experimental | [2] Chevalier 2004; _cites Farmer 1999_ | Table 5, p. 25, row 9; `ORC-AXLSIDKYCG` |  |
| Phase transition | 2660 K | 2660 | other: (U0.65Zr0.35)O2.052 | model | [1] Barrachin 2008 | Table 5, p. 7, row 8; `ORC-CPH53QCRL4` |  |
| Phase transition | 2714 K | 2714 | other: N° 5 (PWR, 30% ox.); _alloy: O 0.59535, U 0.25165, Zr 0.153_ | model | [2] Chevalier 2004 | Table 5, p. 25, row 2; `ORC-HG6E3RJ6UM` |  |
| Phase transition | 2738 K | 2738 | other: N° 5 (PWR, 30% ox.); _alloy: O 0.59535, U 0.25165, Zr 0.153_ | experimental | [2] Chevalier 2004; _cites Farmer 1999_ | Table 5, p. 25, row 1; `ORC-GAOTNRJOLP` |  |
| Phase transition | 2740 K | 2740 | other: N° 9 (BWR, 70% ox.); _alloy: O 0.622, U 0.15462, Zr 0.22338_ | model | [2] Chevalier 2004 | Table 5, p. 25, row 12; `ORC-S6F7UEATDM` |  |
| Phase transition | 2748 K | 2748 | other: N° 9 (BWR, 70% ox.); _alloy: O 0.622, U 0.15462, Zr 0.22338_ | experimental | [2] Chevalier 2004; _cites Farmer 1999_ | Table 5, p. 25, row 11; `ORC-CDMF6AMDUR` |  |
| Phase transition | 2755 K | 2755 | other: (U0.65Zr0.35)O2.098 | experimental | [1] Barrachin 2008; _cites Punni 2001_ | Table 5, p. 7, row 11; `ORC-S5D3GIK7FW` |  |
| Phase transition | 2755 K | 2755 | other: U0.65Zr0.35O2.098; _alloy: O 0.677211, U 0.20981, Zr 0.11297_ | experimental | [2] Chevalier 2004; _cites Punni 2001_ | Table 5, p. 25, row 24; `ORC-6ZEBDL75ZL` |  |
| Phase transition | 2771 K | 2771 | other: (U0.228Zr0.772)O2 | experimental | [1] Barrachin 2008; _cites Lambertson 1953_ | Table 3, p. 4, row 4; `ORC-AQ33M4TEM3` |  |
| Phase transition | 2773 K | 2773 | other: N° 4 (PWR, 50% ox.); _alloy: O 0.61844, U 0.23696, Zr 0.1446_ | experimental | [2] Chevalier 2004; _cites Farmer 1999_ | Table 5, p. 25, row 3; `ORC-WG4PR6CRRK` |  |
| Phase transition | 2789 K | 2789 | other: U0.65Zr0.35O2.098; _alloy: O 0.677211, U 0.20981, Zr 0.11297_ | model | [2] Chevalier 2004 | Table 5, p. 25, row 25; `ORC-UE7EFC7OB7` |  |
| Phase transition | 2790 K | 2790 | other: (U0.486Zr0.514)O2 | experimental | [1] Barrachin 2008; _cites Lambertson 1953_ | Table 3, p. 4, row 3; `ORC-VFOX2WQCO2` |  |
| Phase transition | 2790 K | 2790 | other: U0.65Zr0.35O2.052; _alloy: O 0.67235, U 0.21297, Zr 0.11468_ | model | [2] Chevalier 2004 | Table 5, p. 25, row 21; `ORC-SG2AGJPBDR` |  |
| Phase transition | 2793 K | 2793 | other: N° 6 (PWR, 70% ox.); _alloy: O 0.63945, U 0.2241, Zr 0.13645_ | experimental | [2] Chevalier 2004; _cites Farmer 1999_ | Table 5, p. 25, row 5; `ORC-IJIESMJ5ZI` |  |
| Phase transition | 2804 K | 2804 | other: U0.65Zr0.35O2.098; _alloy: O 0.677211, U 0.20981, Zr 0.11297_ | model | [2] Chevalier 2004 | Table 5, p. 25, row 23; `ORC-B5K732U6FG` |  |
| Phase transition | 2805 K | 2805 | other: (U0.5Zr0.5)O2 | experimental | [1] Barrachin 2008; _cites Ronchi 2002_ [doi](https://doi.org/10.1023/a:1013929816337) | Table 3, p. 4, row 1; `ORC-3TPAK2C7DH` |  |
| Phase transition | 2810 K | 2810 | other: (U0.2Zr0.8)O2 | experimental | [1] Barrachin 2008; _cites Ronchi 2002_ [doi](https://doi.org/10.1023/a:1013929816337) | Table 3, p. 4, row 2; `ORC-GPOJ55WZHS` |  |
| Phase transition | 2812 K | 2812 | other: N° 4 (PWR, 50% ox.); _alloy: O 0.61844, U 0.23696, Zr 0.1446_ | model | [2] Chevalier 2004 | Table 5, p. 25, row 4; `ORC-G3QV6VBJKC` |  |
| Phase transition | 2820 K | 2820 | other: (U0.65Zr0.35)O2.098 | model | [1] Barrachin 2008 | Table 5, p. 7, row 10; `ORC-YSQVFCFN4B` |  |
| Phase transition | 2823 K | 2823 | other: (U0.65Zr0.35)O2.052 | experimental | [1] Barrachin 2008; _cites Punni 2001_ | Table 5, p. 7, row 7; `ORC-WOBZUUO7UP` |  |
| Phase transition | 2823 K | 2823 | other: U0.65Zr0.35O2.052; _alloy: O 0.67235, U 0.21297, Zr 0.11468_ | experimental | [2] Chevalier 2004; _cites Punni 2001_ | Table 5, p. 25, row 20; `ORC-HIEXUXTLWJ` |  |
| Phase transition | 2826 K | 2826 | other: (U0.162Zr0.838)O2 | experimental | [1] Barrachin 2008; _cites Lambertson 1953_ | Table 3, p. 4, row 5; `ORC-CWNZ7E4MSY` |  |
| Phase transition | 2834 K | 2834 | other: (U0.65Zr0.35)O2.098 | experimental | [1] Barrachin 2008; _cites Punni 2001_ | Table 5, p. 7, row 9; `ORC-UZMHPZR6ZB` |  |
| Phase transition | 2834 K | 2834 | other: U0.65Zr0.35O2.098; _alloy: O 0.677211, U 0.20981, Zr 0.11297_ | experimental | [2] Chevalier 2004; _cites Punni 2001_ | Table 5, p. 25, row 22; `ORC-OWQMZLDPQX` |  |
| Phase transition | 2858 K | 2858 | other: U0.65Zr0.35O2.052; _alloy: O 0.67235, U 0.21297, Zr 0.11468_ | model | [2] Chevalier 2004 | Table 5, p. 25, row 19; `ORC-T7GJKN6QYZ` |  |
| Phase transition | 2863 K | 2863 | other: (U0.65Zr0.35)O2.000 | experimental | [1] Barrachin 2008; _cites Punni 2001_ | Table 5, p. 7, row 3; `ORC-UI6Q7DECSF` |  |
| Phase transition | 2863 K | 2863 | other: U0.65Zr0.35O2.000; _alloy: O 0.66667, U 0.21667, Zr 0.11667_ | experimental | [2] Chevalier 2004; _cites Punni 2001_ | Table 5, p. 25, row 16; `ORC-NSMIKWIOZA` |  |
| Phase transition | 2877 K | 2877 | other: U0.65Zr0.35O2.000; _alloy: O 0.66667, U 0.21667, Zr 0.11667_ | model | [2] Chevalier 2004 | Table 5, p. 25, row 17; `ORC-TOGNH3DDY5` |  |
| Phase transition | 2880 K | 2880 | other: (U0.65Zr0.35)O2.052 | model | [1] Barrachin 2008 | Table 5, p. 7, row 6; `ORC-M7R4EJMJ6M` |  |
| Phase transition | 2890 K | 2890 | other: (U0.65Zr0.35)O2.000 | model | [1] Barrachin 2008 | Table 5, p. 7, row 4; `ORC-QWXJDKEGQS` |  |
| Phase transition | 2898 K | 2898 | other: N° 6 (PWR, 70% ox.); _alloy: O 0.63945, U 0.2241, Zr 0.13645_ | model | [2] Chevalier 2004 | Table 5, p. 25, row 6; `ORC-L3IY2R66BG` |  |
| Phase transition | 2911 K | 2911 | other: (U0.65Zr0.35)O2.052 | experimental | [1] Barrachin 2008; _cites Punni 2001_ | Table 5, p. 7, row 5; `ORC-AF2OAHRXME` |  |
| Phase transition | 2911 K | 2911 | other: U0.65Zr0.35O2.052; _alloy: O 0.67235, U 0.21297, Zr 0.11468_ | experimental | [2] Chevalier 2004; _cites Punni 2001_ | Table 5, p. 25, row 18; `ORC-B23EKEQG3E` |  |
| Phase transition | 2936 K | 2936 | other: U0.65Zr0.35O2.000; _alloy: O 0.66667, U 0.21667, Zr 0.11667_ | model | [2] Chevalier 2004 | Table 5, p. 25, row 15; `ORC-E22XRMPVV5` |  |
| Phase transition | 2950 K | 2950 | other: (U0.65Zr0.35)O2.000 | model | [1] Barrachin 2008 | Table 5, p. 7, row 2; `ORC-3L5CLB735A` |  |
| Phase transition | 2951 K | 2951 | other: (U0.65Zr0.35)O2.000 | experimental | [1] Barrachin 2008; _cites Punni 2001_ | Table 5, p. 7, row 1; `ORC-GTAGQNBRQH` |  |
| Phase transition | 2951 K | 2951 | other: U0.65Zr0.35O2.000; _alloy: O 0.66667, U 0.21667, Zr 0.11667_ | experimental | [2] Chevalier 2004; _cites Punni 2001_ | Table 5, p. 25, row 14; `ORC-WYJHG33SZI` |  |

### Phase equilibrium (1)

Table: Phase equilibrium, O–U–Zr system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Phase composition |  | 1519 | (U,Zr)O2-x + α-Zr + U-Zr alloy; _(U,Zr)O2-x: O 0.662, U 0.324, Zr 0.014; α-Zr: O 0.285, U 0.008, Zr 0.707; U-Zr alloy: O 0, U 0.901, Zr 0.099_ | experimental | [3] Quaini 2018 | Table 5, p. 13, row 1; `ORC-ZPOWZG7GU5` |  |

## Sources

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

1. M. Barrachin, P.Y. Chevalier, B. Cheynet, E. Fischer, New modelling of the U–O–Zr phase diagram in the hyper-stoichiometric region and consequences for the fuel rod liquefaction in oxidising conditions, Journal of Nuclear Materials 375, 397-409 (2008). [doi:10.1016/j.jnucmat.2008.02.003](https://doi.org/10.1016/j.jnucmat.2008.02.003)
2. Pierre-Yves Chevalier, Evelyne Fischer, Bertrand Cheynet, Progress in the thermodynamic modelling of the O–U–Zr ternary system, Calphad 28, 15-40 (2004). [doi:10.1016/j.calphad.2004.03.005](https://doi.org/10.1016/j.calphad.2004.03.005)
3. A. Quaini, C. Guéneau, S. Gossé, N. Dupin, B. Sundman, E. Brackx et al., Contribution to the thermodynamic description of the corium – The U-Zr-O system, Journal of Nuclear Materials 501, 104-131 (2018). [doi:10.1016/j.jnucmat.2018.01.023](https://doi.org/10.1016/j.jnucmat.2018.01.023)

## 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/).