# Al–Hf–Ni system

> Al–Hf–Ni system: 22 accepted literature values (invariant reaction 9, formation 8, phase equilibrium 5) and 0 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote.

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

22 accepted literature values from 2 paper(s) (experimental 5, model 17); 0 calculated phase diagram(s).

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

Table: Accepted values by evidence class

| Evidence class | Values |
|---|---:|
| experimental | 5 |
| model | 17 |

Table: Accepted values by property group

| Property group | Values |
|---|---:|
| invariant reaction | 9 |
| phase equilibrium | 5 |
| formation | 8 |

## Invariant reactions (literature)

Table: Invariant reactions reported in the literature for the Al–Hf–Ni system (9)

| T (K) | Reaction / phases | Compositions (mole fraction) | Class | Source | Location | Quote |
|---:|---|---|---|---|---|---|
| 1390 | eutectic: L/Ni2AlHf + Ni64Al20Hf16 | L: Hf 0.18, Ni 0.61 | model | [1] Kaufman 1975 | Table IX, p. 10, row 1; `ORC-FML2UDFJWX` |  |
| 1330 | eutectic: L/Ni3Al + Ni64Al20Hf16 | L: Hf 0.1, Ni 0.68 | model | [1] Kaufman 1975 | Table IX, p. 10, row 2; `ORC-FJGC2WFY72` |  |
| 1320 | eutectic: L/Ni7Hf2 + Ni64Al20Hf16 | L: Hf 0.18, Ni 0.68; Ni7Hf2: Hf 0.222222, Ni 0.777778 | model | [1] Kaufman 1975 | Table IX, p. 10, row 3; `ORC-QUWKCZDA7K` |  |
| 1300 | eutectic: L/Ni2AlHf + Ni7Hf | L: Hf 0.24, Ni 0.64 | model | [1] Kaufman 1975 | Table IX, p. 10, row 4; `ORC-V75H4II3UK` |  |
| 1290 | eutectic: L/Ni7Hf2 + Ni3Al | L: Hf 0.1, Ni 0.76; Ni7Hf2: Hf 0.222222, Ni 0.777778 | model | [1] Kaufman 1975 | Table IX, p. 10, row 5; `ORC-BJMZP3SWUR` |  |
| 1280 | eutectic: L/Ni7Hf2 + fcc + Ni3Al | L: Hf 0.09, Ni 0.79; Ni7Hf2: Hf 0.222222, Ni 0.777778 | model | [1] Kaufman 1975 | Table IX, p. 10, row 7; `ORC-6EYYS6LR2C` |  |
| 1280 | eutectic: L/Ni7Hf2 + Ni3Al + Ni64Al20Hf16 | L: Hf 0.11, Ni 0.74; Ni7Hf2: Hf 0.222222, Ni 0.777778 | model | [1] Kaufman 1975 | Table IX, p. 10, row 8; `ORC-SI7DYYNSP2` |  |
| 1280 | eutectic: L/Ni2AlHf + bcc | L: Hf 0.08, Ni 0.57 | model | [1] Kaufman 1975 | Table IX, p. 10, row 6; `ORC-VSWZXSYRHJ` |  |
| 1260 | eutectic: L/Ni2AlHf + bcc + Ni64Al20Hf16 | L: Hf 0.08, Ni 0.6 | model | [1] Kaufman 1975 | Table IX, p. 10, row 9; `ORC-HBMBBMXXUR` |  |

## Other properties

### Phase equilibrium (5)

Table: Phase equilibrium, Al–Hf–Ni system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Phase composition |  | 1433 | γ + Ni5Hf; _γ: Al 0.0799, Hf 0.0114, Ni 0.9087; Ni5Hf: Al 0.0031, Hf 0.1581, Ni 0.8388_ | experimental | [2] Zhang 2008 | Table 2, p. 4, row 2; `ORC-WYYQ47UN24` |  |
| Phase composition |  | 1433 | γ + γ′; _γ: Al 0.137, Hf 0.0076, Ni 0.8554; γ′: Al 0.1855, Hf 0.0435, Ni 0.771_ | experimental | [2] Zhang 2008 | Table 2, p. 4, row 1; `ORC-2F4QRH644D` |  |
| Phase composition |  | 1433 | γ + γ′ + Ni7Hf2; _γ: Al 0.1228, Hf 0.0114, Ni 0.8658; γ′: Al 0.1689, Hf 0.0588, Ni 0.7723; Ni7Hf2: Al 0.0037, Hf 0.2055, Ni 0.7909_ | experimental | [2] Zhang 2008 | Table 2, p. 4, row 4; `ORC-HIE6VXRNYH` |  |
| Phase composition |  | 1433 | γ + γ′ + Ni7Hf2; _γ: Al 0.1245, Hf 0.0103, Ni 0.8652; γ′: Al 0.1693, Hf 0.0584, Ni 0.7723; Ni7Hf2: Al 0.0036, Hf 0.2042, Ni 0.7922_ | experimental | [2] Zhang 2008 | Table 2, p. 4, row 3; `ORC-Q7QMCOYLY3` |  |
| Phase composition |  | 1433 | γ′ + Ni7Hf2; _γ′: Al 0.1753, Hf 0.0667, Ni 0.758; Ni7Hf2: Al 0.0036, Hf 0.2114, Ni 0.785_ | experimental | [2] Zhang 2008 | Table 2, p. 4, row 5; `ORC-MPAVILG4ON` |  |

### Formation (8)

Table: Formation, Al–Hf–Ni system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Gibbs energy of formation; _printed: Free Energy of Formation_ | -73.6384 kJ/mol (basis unstated) | 300 | Ni2AlHf; _alloy: Hf 0.25, Ni 0.5_ | model | [1] Kaufman 1975 | Table VIII, p. 10, row 6; `ORC-WCJNN3QUKX.306ccc` |  |
| Gibbs energy of formation; _printed: Free Energy of Formation_ | -67.1532 kJ/mol (basis unstated) | 300 | Ni64Al20Hf16; _alloy: Hf 0.16, Ni 0.64_ | model | [1] Kaufman 1975 | Table VIII, p. 10, row 6; `ORC-WCJNN3QUKX.6a400f` |  |
| Gibbs energy of formation; _printed: Free Energy of Formation_ | -75.1028 kJ/mol (basis unstated) | 500 | Ni2AlHf; _alloy: Hf 0.25, Ni 0.5_ | model | [1] Kaufman 1975 | Table VIII, p. 10, row 5; `ORC-ENE2FVGTWM.49a8ef` |  |
| Gibbs energy of formation; _printed: Free Energy of Formation_ | -67.3624 kJ/mol (basis unstated) | 500 | Ni64Al20Hf16; _alloy: Hf 0.16, Ni 0.64_ | model | [1] Kaufman 1975 | Table VIII, p. 10, row 5; `ORC-ENE2FVGTWM.565f15` |  |
| Gibbs energy of formation; _printed: Free Energy of Formation_ | -74.6844 kJ/mol (basis unstated) | 1000 | Ni2AlHf; _alloy: Hf 0.25, Ni 0.5_ | model | [1] Kaufman 1975 | Table VIII, p. 10, row 4; `ORC-F3UOLU6KYH.fa145a` |  |
| Gibbs energy of formation; _printed: Free Energy of Formation_ | -65.6888 kJ/mol (basis unstated) | 1000 | Ni64Al20Hf16; _alloy: Hf 0.16, Ni 0.64_ | model | [1] Kaufman 1975 | Table VIII, p. 10, row 4; `ORC-F3UOLU6KYH.f9224a` |  |
| Gibbs energy of formation; _printed: Free Energy of Formation_ | -73.4292 kJ/mol (basis unstated) | 1200 | Ni2AlHf; _alloy: Hf 0.25, Ni 0.5_ | model | [1] Kaufman 1975 | Table VIII, p. 10, row 3; `ORC-XXKTO7XXIQ.837a08` |  |
| Gibbs energy of formation; _printed: Free Energy of Formation_ | -63.806 kJ/mol (basis unstated) | 1200 | Ni64Al20Hf16; _alloy: Hf 0.16, Ni 0.64_ | model | [1] Kaufman 1975 | Table VIII, p. 10, row 3; `ORC-XXKTO7XXIQ.9aaff3` |  |

## Sources

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

1. L. Kaufman, H. Nesor, Calculation of the Ni-Al-W, Ni-Al-Hf and Ni-Cr-Hf systems, Canadian Metallurgical Quarterly 14, 221-232 (1975). [doi:10.1179/000844375795050157](https://doi.org/10.1179/000844375795050157)
2. C. Zhang, J. Zhu, Y. Yang, H.-B. Cao, F. Zhang, W.-S. Cao et al., Thermodynamic modeling and experimental investigation of the Ni-rich corner of the Ni–Al–Hf system, Intermetallics 16, 139-147 (2008). [doi:10.1016/j.intermet.2007.08.009](https://doi.org/10.1016/j.intermet.2007.08.009)

## 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/).