B–Ta system

74 accepted literature values from 2 paper(s) (experimental 32, model 17, DFT 18, unspecified 7); 0 calculated phase diagram(s). 10 further extracted value(s) not accepted by the reader-agreement checks are only in the JSON/CSV.

Data: JSON · CSV · interactive explorer · phases (13) · papers (bibliography) · Markdown

Accepted values by evidence class
Evidence class	Values
experimental	32
model	17
DFT	18
unspecified	7

Accepted values by property group
Property group	Values
invariant reaction	60
formation	14

Convex hulls: Materials Project DFT hull · OQMD DFT hull · CALPHAD hull TaB-17OuY

Invariant reactions (literature)

Invariant reactions reported in the literature for the B–Ta system (60)
T (K)	Reaction / phases	Compositions (mole fraction)	Class	Source	Location
3303.15	L + TaB -> Ta3B4	L: Ta 0.41; TaB: Ta 0.483; Ta3B4: Ta 0.431	experimental	[1] OuYang 2017 cites Okamoto 1993 doi	Table 2, p. 5, row 1 report
3303	L + TaB(ht) -> Ta3B4	L: B 0.59; TaB(ht): B 0.52; Ta3B4: B 0.56	experimental	[2] Silva 2018 cites Rudy 1969	Table 3, p. 19, row 30 report
3303	L + TaB(ht) -> Ta3B4	L: B 0.57; TaB(ht): B 0.52; Ta3B4: B 0.55	experimental	[2] Silva 2018 cites 393–394 1993	Table 3, p. 19, row 29 report
3300.15	L + TaB -> Ta3B4	L: Ta 0.407; TaB: Ta 0.5; Ta3B4: Ta 0.437	model	[1] OuYang 2017	Table 2, p. 5, row 3 report
3300	L + TaB(ht) -> Ta3B4	L: B 0.593; TaB(ht): B 0.5; Ta3B4: B 0.563	DFT	[2] Silva 2018 cites Zhang 2015 doi	Table 3, p. 19, row 28 report
3284	L + TaB(ht) -> Ta3B4	L: B 0.595; TaB(ht): B 0.495; Ta3B4: B 0.571	model	[2] Silva 2018	Table 3, p. 19, row 27 report
3282.15	eutectic: L -> TaB2 + Ta3B4	L: Ta 0.372; TaB2: Ta 0.334; Ta3B4: Ta 0.437	model	[1] OuYang 2017	Table 2, p. 5, row 6 report
3282	eutectic: L -> TaB2 + Ta3B4	L: B 0.628; TaB2: B 0.666; Ta3B4: B 0.563	DFT	[2] Silva 2018 cites Zhang 2015 doi	Table 3, p. 19, row 32 report
3276	eutectic: L -> TaB2 + Ta3B4	L: B 0.616; TaB2: B 0.673; Ta3B4: B 0.571	model	[2] Silva 2018	Table 3, p. 19, row 31 report
3263.15	eutectic: L -> TaB2 + Ta3B4	L: Ta 0.39; TaB2: Ta 0.381; Ta3B4: Ta 0.422	experimental	[1] OuYang 2017 cites Okamoto 1993 doi	Table 2, p. 5, row 4 report
3263	eutectic: L -> TaB2 + Ta3B4	L: B 0.61; TaB2: B 0.61; Ta3B4: B 0.58	experimental	[2] Silva 2018 cites 393–394 1993	Table 3, p. 19, row 33 report
3263	eutectic: L -> TaB2 + Ta3B4	L: B 0.61; TaB2: B 0.63; Ta3B4: B 0.59	experimental	[2] Silva 2018 cites Rudy 1969	Table 3, p. 19, row 34 report
3253.15	L + TaB -> Ta3B4	L: Ta 0.437; TaB: Ta 0.5; Ta3B4: Ta 0.439	unspecified	[1] OuYang 2017 cites Kaufman 1991 doi	Table 2, p. 5, row 2 report
3223.15	eutectic: L -> TaB2 + Ta3B4	L: Ta 0.419; TaB2: Ta 0.333; Ta3B4: Ta 0.437	unspecified	[1] OuYang 2017 cites Kaufman 1991 doi	Table 2, p. 5, row 5 report
3168	Ta3B4 + TaB(ht) -> TaB(rt)	Ta3B4: B 0.571; TaB(ht): B 0.496	model	[2] Silva 2018	Table 3, p. 19, row 25 report
3008	TaB(ht) -> TaB(rt) + L	TaB(ht): B 0.487; TaB(rt): B 0.5; L: B 0.285	model	[2] Silva 2018	Table 3, p. 19, row 24 report
2848	Ta3B4 + TaB(rt) -> Ta5B6	Ta3B4: B 0.571; TaB(rt): B 0.5; Ta5B6: B 0.545	model	[2] Silva 2018	Table 3, p. 19, row 26 report
2748.15	L + TaB -> Ta2B	L: Ta 0.758; TaB: Ta 0.5; Ta2B: Ta 0.667	unspecified	[1] OuYang 2017 cites Kaufman 1991 doi	Table 2, p. 5, row 8 report
2718.15	eutectic: L -> Ta2B + (Ta)	L: Ta 0.785; Ta2B: Ta 0.667; (Ta): Ta 0.988	unspecified	[1] OuYang 2017 cites Kaufman 1991 doi	Table 2, p. 5, row 11 report
2691	L + TaB(rt) -> Ta2B	L: B 0.212; TaB(rt): B 0.5; Ta2B: B 0.295	model	[2] Silva 2018	Table 3, p. 19, row 7 report
2690.15	L + TaB -> Ta2B	L: Ta 0.731; TaB: Ta 0.501; Ta2B: Ta 0.712	experimental	[1] OuYang 2017 cites Okamoto 1993 doi	Table 2, p. 5, row 7 report
2690	L + TaB(rt) -> Ta2B	L: B 0.27; TaB(rt): B 0.49; Ta2B: B 0.3	experimental	[2] Silva 2018 cites Rudy 1969	Table 3, p. 19, row 12 report
2658	eutectic: L -> Ta2B + BCC	L: B 0.23; Ta2B: B 0.28; BCC: B 0.02	experimental	[2] Silva 2018 cites Rudy 1969	Table 3, p. 19, row 6 report
2657.15	L + TaB -> Ta2B	L: Ta 0.821; TaB: Ta 0.5; Ta2B: Ta 0.667	model	[1] OuYang 2017	Table 2, p. 5, row 9 report
2657	L + TaB(rt) -> Ta2B	L: B 0.179; TaB(rt): B 0.5; Ta2B: B 0.333	DFT	[2] Silva 2018 cites Zhang 2015 doi	Table 3, p. 19, row 8 report
2653	L + TaB(rt) -> Ta2B	L: B 0.27; TaB(rt): B 0.49; Ta2B: B 0.29	experimental	[2] Silva 2018 cites 393–394 1993	Table 3, p. 19, row 10 report
2653	L + TaB(rt) -> Ta2B	TaB(rt): B 0.5, Ta 0.5; Ta2B: B 0.333333, Ta 0.666667	experimental	[2] Silva 2018 cites System 1971	Table 3, p. 19, row 11 report
2638	eutectic: L -> Ta2B + BCC	L: B 0.187; Ta2B: B 0.279; BCC: B 0.026	model	[2] Silva 2018	Table 3, p. 19, row 1 report
2633.15	eutectic: L -> Ta2B + (Ta)	L: Ta 0.77; Ta2B: Ta 0.701; (Ta): Ta 0.98	experimental	[1] OuYang 2017 cites Okamoto 1993 doi	Table 2, p. 5, row 10 report
2633	eutectic: L -> Ta2B + BCC	L: B 0.23; Ta2B: B 0.28; BCC: B 0.02	experimental	[2] Silva 2018 cites 393–394 1993	Table 3, p. 19, row 4 report
2633	eutectic: L -> Ta2B + BCC	Ta2B: B 0.333333, Ta 0.666667	experimental	[2] Silva 2018 cites System 1971	Table 3, p. 19, row 5 report
2630.15	eutectic: L -> Ta2B + (Ta)	L: Ta 0.829; Ta2B: Ta 0.667; (Ta): Ta 0.967	model	[1] OuYang 2017	Table 2, p. 5, row 13 report
2630	eutectic: L -> Ta2B + BCC	L: B 0.171; Ta2B: B 0.333; BCC: B 0.033	DFT	[2] Silva 2018 cites Zhang 2015 doi	Table 3, p. 19, row 2 report
2503.15	TaB + Ta2B -> Ta3B2	TaB: Ta 0.5; Ta2B: Ta 0.667; Ta3B2: Ta 0.6	unspecified	[1] OuYang 2017 cites Kaufman 1991 doi	Table 2, p. 5, row 15 report
2453.15	TaB + Ta2B -> Ta3B2	TaB: Ta 0.505; Ta2B: Ta 0.667; Ta3B2: Ta 0.59	experimental	[1] OuYang 2017 cites Okamoto 1993 doi	Table 2, p. 5, row 14 report
2453.15	TaB + Ta2B -> Ta3B2	TaB: Ta 0.5; Ta2B: Ta 0.667; Ta3B2: Ta 0.6	model	[1] OuYang 2017	Table 2, p. 5, row 16 report
2453	TaB(rt) + Ta2B -> Ta3B2	TaB(rt): B 0.495; Ta2B: B 0.31; Ta3B2: B 0.41	experimental	[2] Silva 2018 cites 393–394 1993	Table 3, p. 19, row 21 report
2453	TaB(rt) + Ta2B -> Ta3B2	TaB(rt): B 0.5; Ta2B: B 0.32; Ta3B2: B 0.4	experimental	[2] Silva 2018 cites Rudy 1969	Table 3, p. 19, row 23 report
2453	TaB(rt) + Ta2B -> Ta3B2	TaB(rt): B 0.5; Ta2B: B 0.333; Ta3B2: B 0.4	DFT	[2] Silva 2018 cites Zhang 2015 doi	Table 3, p. 19, row 20 report
2445	TaB(rt) + Ta2B -> Ta3B2	TaB(rt): B 0.5; Ta2B: B 0.306; Ta3B2: B 0.4	model	[2] Silva 2018	Table 3, p. 19, row 19 report
2343.15	eutectic: L -> (B) + TaB2	L: Ta 0.02; (B): Ta 0; TaB2: Ta 0.26	experimental	[1] OuYang 2017 cites Okamoto 1993 doi	Table 2, p. 5, row 19 report
2343	eutectic: L -> (βB) + TaB2	TaB2: B 0.666667, Ta 0.333333	experimental	[2] Silva 2018 cites System 1971	Table 3, p. 19, row 38 report
2343	eutectic: L -> (βB) + TaB2	L: B 0.98; (βB): B 0.99; TaB2: B 0.74	experimental	[2] Silva 2018 cites 393–394 1993	Table 3, p. 19, row 37 report
2329.15	eutectic: L -> (B) + TaB2	L: Ta 0.0179; (B): Ta 0; TaB2: Ta 0.256	model	[1] OuYang 2017	Table 2, p. 5, row 20 report
2329	eutectic: L -> (βB) + TaB2	L: B 0.982; (βB): B 1; TaB2: B 0.744	DFT	[2] Silva 2018 cites Zhang 2015 doi	Table 3, p. 19, row 36 report
2328.15	eutectic: L -> (B) + TaB2	L: Ta 0.035; (B): Ta 9.000e-4; TaB2: Ta 0.261	experimental	[1] OuYang 2017 cites Leitnaker 1961 doi	Table 2, p. 5, row 17 report
2328	eutectic: L -> (βB) + TaB2	L: B 0.98; (βB): B 1; TaB2: B 0.74	experimental	[2] Silva 2018 cites Rudy 1969	Table 3, p. 19, row 39 report
2325	eutectic: L -> (βB) + TaB2	L: B 0.978; (βB): B 1; TaB2: B 0.728	model	[2] Silva 2018	Table 3, p. 19, row 35 report
2313.15	Ta2B -> Ta3B2 + (Ta)	Ta2B: Ta 0.7; Ta3B2: Ta 0.61; (Ta): Ta 1	experimental	[1] OuYang 2017 cites Okamoto 1993 doi	Table 2, p. 5, row 21 report
2313	Ta2B -> BCC + Ta3B2	Ta2B: B 0.3; BCC: B 0; Ta3B2: B 0.39	experimental	[2] Silva 2018 cites 393–394 1993	Table 3, p. 19, row 16 report
2313	Ta2B -> BCC + Ta3B2	Ta2B: B 0.3; BCC: B 0.01; Ta3B2: B 0.38	experimental	[2] Silva 2018 cites Rudy 1969	Table 3, p. 19, row 18 report
2313	Ta2B -> BCC + Ta3B2	Ta2B: B 0.333333, Ta 0.666667; Ta3B2: B 0.4, Ta 0.6	experimental	[2] Silva 2018 cites System 1971	Table 3, p. 19, row 17 report
2243	TaB(rt) + Ta2B -> Ta3B2	TaB(rt): B 0.5, Ta 0.5; Ta2B: B 0.333333, Ta 0.666667; Ta3B2: B 0.4, Ta 0.6	experimental	[2] Silva 2018 cites System 1971	Table 3, p. 19, row 22 report
2219.15	Ta2B -> Ta3B2 + (Ta)	Ta2B: Ta 0.667; Ta3B2: Ta 0.6; (Ta): Ta 0.992	model	[1] OuYang 2017	Table 2, p. 5, row 24 report
2219	Ta2B -> BCC + Ta3B2	Ta2B: B 0.333; BCC: B 0.008; Ta3B2: B 0.4	DFT	[2] Silva 2018 cites Zhang 2015 doi	Table 3, p. 19, row 14 report
2206	Ta2B -> BCC + Ta3B2	Ta2B: B 0.303; BCC: B 0.006; Ta3B2: B 0.4	model	[2] Silva 2018	Table 3, p. 19, row 13 report
2198	Ta2B -> BCC + Ta3B2	Ta2B: B 0.333333, Ta 0.666667; Ta3B2: B 0.4, Ta 0.6	experimental	[2] Silva 2018 cites Chad 2006 doi	Table 3, p. 19, row 15 report
2193.15	Ta2B -> Ta3B2 + (Ta)	Ta2B: Ta 0.667; Ta3B2: Ta 0.6; (Ta): Ta 0.987	unspecified	[1] OuYang 2017 cites Kaufman 1991 doi	Table 2, p. 5, row 22 report
2183.15	eutectic: L -> (B) + TaB2	L: Ta 0.062; (B): Ta 0; TaB2: Ta 0.333	unspecified	[1] OuYang 2017 cites Kaufman 1991 doi	Table 2, p. 5, row 18 report
2173.15	Ta2B -> Ta3B2 + (Ta)	Ta2B: B 0.333333, Ta 0.666667; Ta3B2: B 0.4, Ta 0.6	experimental	[1] OuYang 2017 cites Chad 2006 doi	Table 2, p. 5, row 23 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, B–Ta system (14)
Phase	Compound	Value	T (K)	Class	MP DFT (kJ/mol-atom)	OQMD DFT (kJ/mol-atom)	Source	Location
Ta2B		-63.842 kJ/mol-atom	0	DFT			[1] OuYang 2017	Table 1, p. 4, row 1 report
Ta2B		-51.973 kJ/mol-atom	0	DFT			[1] OuYang 2017 cites Zhang 2015 doi	Table 1, p. 4, row 3 report
Ta3B2		-71.3 kJ/mol-atom	0	DFT			[1] OuYang 2017 cites Qi 2014	Table 1, p. 4, row 6 report
Ta3B2		-67.647 kJ/mol-atom	0	DFT			[1] OuYang 2017	Table 1, p. 4, row 4 report
Ta3B4		-80.055 kJ/mol-atom	0	DFT			[1] OuYang 2017 cites Zhang 2015 doi	Table 1, p. 4, row 13 report
Ta3B4		-76.212 kJ/mol-atom	0	DFT			[1] OuYang 2017	Table 1, p. 4, row 11 report
TaB		-83.5 kJ/mol-atom	0	DFT			[1] OuYang 2017 cites Qi 2013	Table 1, p. 4, row 10 report
TaB		-83.218 kJ/mol-atom	0	DFT			[1] OuYang 2017 cites Zhang 2015 doi	Table 1, p. 4, row 9 report
TaB		-81.007 kJ/mol-atom	0	DFT			[1] OuYang 2017	Table 1, p. 4, row 7 report
TaB2		-67.7 kJ/mol-atom	0	DFT			[1] OuYang 2017 cites Zhang 2015 doi	Table 1, p. 4, row 16 report
TaB2	TaB2	-64.9 kJ/mol-atom	298.15	experimental	-62.64 (mp-aaaaabqq)	-62.619 (oqmd-5807)	[1] OuYang 2017 cites Kirpichev 1979	Table 1, p. 4, row 17 report
TaB2		-64.062 kJ/mol-atom	0	DFT			[1] OuYang 2017	Table 1, p. 4, row 14 report
TaB2	TaB2	-62.9 kJ/mol-atom	298.15	experimental	-62.64 (mp-aaaaabqq)	-62.619 (oqmd-5807)	[1] OuYang 2017 cites Johnson 1967 doi	Table 1, p. 4, row 18 report
TaB2	TaB2	-53.3 kJ/mol-atom	298.15	experimental	-62.64 (mp-aaaaabqq)	-62.619 (oqmd-5807)	[1] OuYang 2017 cites Meschel 1993 doi	Table 1, p. 4, row 19 report

Sources

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

Xuemei OuYang, Fucheng Yin, Jingxian Hu, Ye Liu, Zhaohui Long, Thermodynamic Modeling of B-Ta and B-C-Ta Systems, J. Phase Equilib. Diffus. 38, 874-886 (2017). doi:10.1007/s11669-017-0603-2
Antonio Augusto Araujo Pinto da Silva, Flavio Ferreira, Belmira Benedita de Lima-Kühn, Gilberto Carvalho Coelho, Carlos Angelo Nunes, Pauline Vilasi et al., The Ta-B system: Key experiments and thermodynamic modeling, Calphad 63, 107-115 (2018). doi:10.1016/j.calphad.2018.08.012

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-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); 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); 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. 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_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}
}