B–C system

26 accepted literature values from 3 paper(s) (experimental 11, model 6, DFT 1, unspecified 8); 5 calculated phase diagram(s). 2 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	11
model	6
DFT	1
unspecified	8

Accepted values by property group
Property group	Values
invariant reaction	6
phase transition	4
crystal structure	16

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
BC-12Sae.tdb	A. Saengdeejing, J.E. Saal, V.R. Manga, Z.-K. Liu, Acta Mater., 60, 7207-15(2012). doi:10.1016/j.actamat.2012.09.029	`290e26418cf735dd70704dac68cd7a0fce5ebcbae022dae8e6564cf4428d4443`	viewer · TDB · JSON
BC-14Rog.tdb	P.F. Rogl, J. Vrestal, T. Tanaka, S. Takenouchi, Calphad, 44, 3-9(2014). doi:10.1016/j.calphad.2013.07.016	`61f54c7a828b16dd1b5f97b5d6347435c4e3f12f18c2e1fb107711a3f01c50fd`	viewer · TDB · JSON
BC-24Eno.tdb	M. Enoki, K. Takahashi, H. Ohtani, J. Phase Equilib. Diffus., 45, 1244-59(2024). doi:10.1007/s11669-024-01162-3	`2105df9640f51822c3c2136103639fa17207e940e11619555415087de090b04b`	viewer · TDB · JSON
BC-94Kas.tdb	B. Kasper, PhD Thesis, Stuttgart, Germany, 1994.	`178cb3073b3b2693468b4728a05ac774749084a7bc39cab3beca920705d1a77d`	viewer · TDB · JSON
BC-98Kas-LB.tdb	B. Kasper, COST 507, Final report round 2, 1998.	`953024537b05421efafa226f8e8c54f9faa82b3221cdef0e2468e32e5d63606f`	viewer · TDB · JSON

Calculated three-phase invariants (model, mole fraction of the second component)
TDB file	T (K)	Phases at the invariant
BC-12Sae.tdb	2718.71	B4C_D1G#2 (x(C) 0.15548) + LIQUID (x(C) 0.16366) + B4C_D1G (x(C) 0.18135)
BC-12Sae.tdb	2660	B4C_D1G (x(C) 0.19193) + LIQUID (x(C) 0.29217) + GRAPHITE_A9 (x(C) 0.97897)
BC-12Sae.tdb	2408.12	LIQUID (x(C) 0.00156) + BETA_RHOMBO_B (x(C) 0.0123) + B4C_D1G (x(C) 0.08905)
BC-12Sae.tdb	348.6	B4C_D1G (x(C) 0.1764) + B4C_D1G#2 (x(C) 0.18033) + GRAPHITE_A9 (x(C) 1)
BC-14Rog.tdb	2624.09	B4C_D1G (x(C) 0.19557) + LIQUID (x(C) 0.29373) + GRAPHITE_A9 (x(C) 0.9781)
BC-14Rog.tdb	2373.84	LIQUID (x(C) 0.00758) + BETA_RHOMBO_B (x(C) 0.01427) + B4C_D1G (x(C) 0.0986)
BC-24Eno.tdb	2713.09	B4C_D1G#2 (x(C) 0.15556) + LIQUID (x(C) 0.16694) + B4C_D1G (x(C) 0.18132)
BC-24Eno.tdb	2668.64	B4C_D1G (x(C) 0.19194) + LIQUID (x(C) 0.27825) + GRAPHITE_A9 (x(C) 0.97882)
BC-24Eno.tdb	2407.88	LIQUID (x(C) 0.00179) + BETA_RHOMBO_B (x(C) 0.0123) + B4C_D1G (x(C) 0.08905)
BC-24Eno.tdb	348.6	B4C_D1G (x(C) 0.1764) + B4C_D1G#2 (x(C) 0.18033) + GRAPHITE_A9 (x(C) 1)
BC-94Kas.tdb	2647.86	B4C_D1G (x(C) 0.18517) + LIQUID (x(C) 0.29053) + GRAPHITE_A9 (x(C) 0.98175)
BC-94Kas.tdb	2346.16	BETA_RHOMBO_B (x(C) 0) + LIQUID (x(C) 0.00198) + B4C_D1G (x(C) 0.08128)
BC-98Kas-LB.tdb	2663.41	B4C_D1G (x(C) 0.19535) + LIQUID (x(C) 0.2925) + GRAPHITE_A9 (x(C) 0.97686)
BC-98Kas-LB.tdb	2375.87	LIQUID (x(C) 0.00566) + BETA_RHOMBO_B (x(C) 0.01428) + B4C_D1G (x(C) 0.09862)

Convex hulls: Materials Project DFT hull · OQMD DFT hull · CALPHAD hull BC-12Sae · CALPHAD hull BC-14Rog · CALPHAD hull BC-94Kas · CALPHAD hull BC-98Kas-LB

Invariant reactions (literature)

Invariant reactions reported in the literature for the B–C system (6)
T (K)	Reaction / phases	Compositions (mole fraction)	Class	Source	Location
2663.4	eutectic: Liquid -> B4C + graphite	Liquid: C 0.292; B4C: C 0.195; graphite: C 0.977	model	[1] (ed.) 1998	Table I, p. 135, row 1 report
2648	Liquid -> B4+xC + Graphite	Liquid: C 0.29; B4+xC: C 0.188	model	[2] Saengdeejing 2012	Table 5, p. 7, row 3 report
2648	Liquid -> B4+xC + Graphite	Liquid: C 0.29; B4+xC: C 0.199	experimental	[2] Saengdeejing 2012 cites Elliott 1961	Table 5, p. 7, row 4 report
2408	Liquid + B4+xC -> β-boron	Liquid: C 9.000e-4; B4+xC: C 0.089	model	[2] Saengdeejing 2012	Table 5, p. 7, row 5 report
2375.9	peritectic: Liquid + B4C -> β-rhombo-B	Liquid: C 0.0056; B4C: C 0.099; β-rhombo-B: C 0.01	model	[1] (ed.) 1998	Table I, p. 135, row 2 report
2348	Liquid + B4+xC -> β-boron	Liquid: C 0.001; B4+xC: C 0.095	experimental	[2] Saengdeejing 2012 cites Elliott 1961	Table 5, p. 7, row 6 report

Other properties

Phase transition (4)

Phase transition, B–C system
Property	Value	T (K)	Phases / composition	Class	Source	Location	Quote
Phase transition	1388 K	1388	a-boron = b-boron	DFT	[2] Saengdeejing 2012 cites Shang 2007 doi	p. 2 report	Using density functional theory, Shang et al. [20] showed that a-boron is more stable than bboron at low temperatures in the defect-free structure and predicted the a to b transition temperature at 1388 K.
Phase transition	2720 K	2720	Liquid -> B4+xC Liquid: C 0.2; B4+xC: C 0.2	model	[2] Saengdeejing 2012	Table 5, p. 7, row 1 report
Phase transition	2723 K	2723	Liquid -> B4+xC Liquid: C 0.2; B4+xC: C 0.2	experimental	[2] Saengdeejing 2012 cites Beauvy 1983 doi	Table 5, p. 7, row 2 report
Phase transition	2725.3 K	2725.3	congruent melting: B4C -> Liquid B4C: C 0.184; Liquid: C 0.184	model	[1] (ed.) 1998	Table I, p. 135, row 3 report

Crystal structure (16)

Crystal structure, B–C system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Lattice a	5.607 Å	298.15	B4C alloy: C 0.2	experimental	[3] Duschanek 1995 cites ref. 85Vil	Table 3, p. 5, row 35 report
Lattice a	5.651 Å	298.15	B4C alloy: C 0.2	unspecified	[3] Duschanek 1995 cites ref. 85Vil	Table 3, p. 4, row 62 report
Lattice a	5.651 Å	298.15	B4C alloy: C 0.2	experimental	[3] Duschanek 1995 cites ref. 85Vil	Table 3, p. 5, row 34 report
Lattice a	5.607 Å	298.15	B4C alloy: C 0.2	unspecified	[3] Duschanek 1995 cites ref. 85Vil	Table 3, p. 4, row 63 report
Lattice a	5.597 Å	2673.15	B4C alloy: C 0.2	unspecified	[3] Duschanek 1995 cites ref. 86Ord	Table 3, p. 4, row 65 report
Lattice a	5.597 Å	2673.15	B4C alloy: C 0.2	experimental	[3] Duschanek 1995 cites ref. 86Ord	Table 3, p. 5, row 37 report
Lattice a	5.598 Å	2723.15	B4C alloy: C 0.2	unspecified	[3] Duschanek 1995 cites ref. 86Ord	Table 3, p. 4, row 64 report
Lattice a	5.598 Å	2723.15	B4C alloy: C 0.2	experimental	[3] Duschanek 1995 cites ref. 86Ord	Table 3, p. 5, row 36 report
Lattice c	12.095 Å	298.15	B4C alloy: C 0.2	experimental	[3] Duschanek 1995 cites ref. 85Vil	Table 3, p. 5, row 35 report
Lattice c	12.196 Å	298.15	B4C alloy: C 0.2	unspecified	[3] Duschanek 1995 cites ref. 85Vil	Table 3, p. 4, row 62 report
Lattice c	12.196 Å	298.15	B4C alloy: C 0.2	experimental	[3] Duschanek 1995 cites ref. 85Vil	Table 3, p. 5, row 34 report
Lattice c	12.095 Å	298.15	B4C alloy: C 0.2	unspecified	[3] Duschanek 1995 cites ref. 85Vil	Table 3, p. 4, row 63 report
Lattice c	12.12 Å	2673.15	B4C alloy: C 0.2	unspecified	[3] Duschanek 1995 cites ref. 86Ord	Table 3, p. 4, row 65 report
Lattice c	12.12 Å	2673.15	B4C alloy: C 0.2	experimental	[3] Duschanek 1995 cites ref. 86Ord	Table 3, p. 5, row 37 report
Lattice c	12.12 Å	2723.15	B4C alloy: C 0.2	unspecified	[3] Duschanek 1995 cites ref. 86Ord	Table 3, p. 4, row 64 report
Lattice c	12.12 Å	2723.15	B4C alloy: C 0.2	experimental	[3] Duschanek 1995 cites ref. 86Ord	Table 3, p. 5, row 36 report

Sources

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

I. Ansara, A. T. Dinsdale, M. H. Rand (eds.), COST 507: Thermochemical database for light metal alloys, Volume 2, EUR 18499 EN, Office for Official Publications of the European Communities, Luxembourg (1998), ISBN 92-828-3902-8.
Arkapol Saengdeejing, James E. Saal, Venkateswara Rao Manga, Zi-Kui Liu, Defects in boron carbide: First-principles calculations and CALPHAD modeling, Acta Materialia 60, 7207-7215 (2012). doi:10.1016/j.actamat.2012.09.029
H. Duschanek, P. Rogl, H. L. Lukas, A critical assessment and thermodynamic calculation of the boron-carbon-titanium (B-C-Ti) ternary system, JPE 16, 46-60 (1995). doi:10.1007/bf02646248

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}
}