Hf–V system

24 accepted literature values from 1 paper(s) (experimental 8, model 16); 1 calculated phase diagram(s). 15 further extracted value(s) not accepted by the reader-agreement checks are only in the JSON/CSV.

Data: JSON · CSV · interactive explorer · interactive phase diagram · phases (5) · papers (bibliography) · Markdown

Accepted values by evidence class
Evidence class	Values
experimental	8
model	16

Accepted values by property group
Property group	Values
invariant reaction	12
phase transition	4
formation	4
mixing / partial	4

Calculated phase diagrams

Binary phase diagrams calculated with pycalphad 0.11.2 from the SGTE binary collection (Hallstedt 2025, CC BY 4.0). Evidence class: model.

Assessments with a calculated phase diagram
TDB file	Assessment	SHA-256	Links
HfV-05Ser.tdb	C. Servant, J. Phase Equilib. Diffus., 26, 39-49(2005). doi:10.1361/15477030522464	`5eb8c7c45b64d39e5506d60ca92a8105b8ab1252eeccf8f392652a2363f392fc`	viewer · TDB · JSON

Calculated three-phase invariants (model, mole fraction of the second component)
TDB file	T (K)	Phases at the invariant
HfV-05Ser.tdb	1807.52	C15_LAVES (x(V) 0.67472) + LIQUID (x(V) 0.6923) + BCC_A2 (x(V) 0.97334)
HfV-05Ser.tdb	1733.12	BCC_A2 (x(V) 0.24261) + LIQUID (x(V) 0.46083) + C15_LAVES (x(V) 0.64035)
HfV-05Ser.tdb	1466.17	HCP_A3 (x(V) 0.02651) + BCC_A2 (x(V) 0.18619) + C15_LAVES (x(V) 0.64465)

Convex hulls: Materials Project DFT hull · OQMD DFT hull

Invariant reactions (literature)

Invariant reactions reported in the literature for the Hf–V system (12)
T (K)	Reaction / phases	Class	Source	Location
2266.15	eutectoid: bcc_A2 -> C15-Laves + cph_A3	experimental	[1] Servant 2005 cites Rudy 1968 doi	Table 3, p. 3, row 15 report
1808.15	eutectic: L -> bcc_A2 + C15-Laves	model	[1] Servant 2005	Table 3, p. 3, row 5 report
1804.15	eutectic: L -> bcc_A2 + C15-Laves	model	[1] Servant 2005	Table 2, p. 3, row 6 report
1793.15	eutectic: L -> bcc_A2 + C15-Laves	experimental	[1] Servant 2005 cites Rudy 1968 doi	Table 3, p. 3, row 7 report
1793.15	eutectic: L -> bcc_A2 + C15-Laves	experimental	[1] Servant 2005 cites Smith 1990	Table 3, p. 3, row 8 report
1733.15	eutectic: L -> bcc_A2 + C15-Laves	model	[1] Servant 2005	Table 3, p. 3, row 9 report
1731.15	eutectic: L -> bcc_A2 + C15-Laves	model	[1] Servant 2005	Table 2, p. 3, row 10 report
1729.15	eutectic: L -> bcc_A2 + C15-Laves	experimental	[1] Servant 2005 cites Smith 1990	Table 3, p. 3, row 12 report
1726.15	eutectic: L -> bcc_A2 + C15-Laves	experimental	[1] Servant 2005 cites Rudy 1968 doi	Table 2, p. 3, row 11 report
1473.15	eutectoid: bcc_A2 -> C15-Laves + cph_A3	model	[1] Servant 2005	Table 3, p. 3, row 14 report
1466.15	eutectoid: bcc_A2 -> C15-Laves + cph_A3	model	[1] Servant 2005	Table 3, p. 3, row 13 report
1463.15	eutectoid: bcc_A2 -> C15-Laves + cph_A3	experimental	[1] Servant 2005 cites Smith 1990	Table 3, p. 3, row 16 report

Formation enthalpies

Literature values in kJ/mol-atom where the per-atom basis is known. DFT columns: the lowest-energy entry at the same composition (Materials Project 2026.04.13, OQMD v1.8; different energy references, never averaged), from dft_parity.json.

Enthalpies of formation, Hf–V system (4)
Phase	Value	T (K)	Class	Source	Location
Laves	-3.344 kJ/mol (basis unstated)	298.15	model	[1] Servant 2005	Table 1, p. 2, row 2 report
Laves	-3.204 kJ/mol (basis unstated)	298.15	model	[1] Servant 2005	Table 1, p. 2, row 4 report
Laves phase	-3.5 kJ/mol (basis unstated)	298.15	model	[1] Servant 2005	Table 1, p. 2, row 3 report
Laves phase	-2.813 kJ/mol (basis unstated)	298.15	model	[1] Servant 2005	Table 1, p. 2, row 5 report

Other properties

Phase transition (4)

Phase transition, Hf–V system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Phase transition	1805.65 K	1805.65	congruent melting: L -> C15 Laves	model	[1] Servant 2005	Table 3, p. 3, row 2 report
Phase transition	1809.15 K	1809.15	congruent melting: L -> C15 Laves	model	[1] Servant 2005	Table 3, p. 3, row 1 report
Phase transition	1823.15 K	1823.15	congruent melting: L -> C15 Laves	experimental	[1] Servant 2005 cites Smith 1990	Table 3, p. 3, row 4 report
Phase transition	1825.15 K	1825.15	congruent melting: L -> C15 Laves	experimental	[1] Servant 2005 cites Rudy 1968 doi	Table 3, p. 3, row 3 report

Mixing / partial (4)

Mixing / partial, Hf–V system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Enthalpy of mixing printed: ΔHmelting	-5.528 kJ/mol (basis unstated)	298.15	liquid alloy: Hf 0.5, V 0.5	model	[1] Servant 2005	Table 1, p. 2, row 2 report
Enthalpy of mixing printed: ΔHmelting	-4.67 kJ/mol (basis unstated)	298.15	liquid alloy: Hf 0.5, V 0.5	model	[1] Servant 2005	Table 1, p. 2, row 4 report
Enthalpy of mixing printed: ΔHmelting	-4.42 kJ/mol (basis unstated)	298.15	liquid alloy: Hf 0.5, V 0.5	model	[1] Servant 2005	Table 1, p. 2, row 3 report
Enthalpy of mixing printed: ΔHmelting	-4.692 kJ/mol (basis unstated)	298.15	liquid alloy: Hf 0.5, V 0.5	model	[1] Servant 2005	Table 1, p. 2, row 5 report

Sources

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

C. Servant, Thermodynamic Assessments of the Phase Diagrams of the Hafnium-Vanadium and Vanadium-Zirconium Systems, Journal of Phase Equilibria & Diffusion 26, 39-49 (2005). doi:10.1361/15477030522464

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). doi:10.5281/zenodo.23735569
R. Arróyave, J. Saal, D. Shin, ORCHID-Diagrams: calculated binary phase diagrams (version 2026.10), Zenodo (2026). doi:10.5281/zenodo.23735859
R. Arróyave, J. Saal, D. Shin, ORCHID-Hulls: binary convex hulls (Materials Project, OQMD, assessed CALPHAD) (version 2026.10), Zenodo (2026). doi:10.5281/zenodo.23735891
R. Arróyave, J. Saal, D. Shin, ORCHID data: umbrella record of the ORCHID datasets (version 2026.10; Version 1, machine-extracted), Zenodo (2026). doi: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.

@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_phase_diagrams_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Diagrams: calculated binary phase diagrams}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735859},
  url       = {https://doi.org/10.5281/zenodo.23735859}
}

@misc{orchid_hulls_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Hulls: binary convex hulls (Materials Project, OQMD, assessed CALPHAD)}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735891},
  url       = {https://doi.org/10.5281/zenodo.23735891}
}

@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}
}