Co–Hf phases

11 phases (tier A 7, tier C 1, liquid 1, needs_review 2); 11 stable in a calculated diagram. Structure types are assigned only when the stored evidence supports an assignment under the stated tier rules (tier A: standard phase name; tier B: unique Materials Project + OQMD on-hull match, DFT-supported; tier C: one structure stated by the assessment's crystallographic table, assessor-stated); other phases list candidates and are marked needs_review. Stability is from phase diagrams calculated with pycalphad from the SGTE binary collection (evidence class: model).

Data: interactive registry · full JSON · Co–Hf system page · Markdown · field reference

Phases of the Co–Hf system (11)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BCC_A2 phase:co-hf:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 3 of 3 calculated diagram(s): 1480–3999.74 K, x(Hf) 0.84811–1	5	5
B2_BCC phase:co-hf:bcc-b2	CsCl · B2 · cP2 · Pm-3m (221)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–3531.03 K, x(Hf) 0.48209–1	8	2
C15_LAVES phase:co-hf:c15-laves	Cu2Mg · C15 · cF24 · Fd-3m (227)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–1895.96 K, x(Hf) 0.25028–0.34687	20	2
CO11HF2 phase:co-hf:co11hf2		needs_review	stable in 2 of 2 calculated diagram(s): 928.48–1545.8 K, x(Hf) 0.15385–0.15385	9	2
CO23HF6_D8A phase:co-hf:co23hf6-d8a	Mn23Th6 · D8_a · cF116 · Fm-3m (225)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–1600 K, x(Hf) 0.2069–0.2069	11	2
CO2HF_C15 phase:co-hf:co2hf-c15	Cu2Mg · C15 · cF24 · Fd-3m (227)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–2065.65 K, x(Hf) 0.33333–0.33333	0	1
COHF_B2 phase:co-hf:cohf-b2		needs_review	stable in 1 of 1 calculated diagram(s): 300–2028.18 K, x(Hf) 0.5–0.5	0	1
COHF2 phase:co-hf:cohf2	NiTi2 · cF96 · Fd-3m (227)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 3 of 3 calculated diagram(s): 300–1699.29 K, x(Hf) 0.65937–0.68042	20	3
FCC_A1 phase:co-hf:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 3 of 3 calculated diagram(s): 694.96–1773.17 K, x(Hf) 0–0.01466	8	3
HCP_A3 phase:co-hf:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	stable in 3 of 3 calculated diagram(s): 300–2500.33 K, x(Hf) 0–1	4	3
LIQUID phase:co-hf:liquid	liquid	liquid	stable in 3 of 3 calculated diagram(s): 1516.31–4000 K, x(Hf) 0–1	25	3

BCC_A2 (Co–Hf)

Id: phase:co-hf:bcc-a2; status assigned
Structure: W · A2 · cI2 · Im-3m (229); type st:a2-w-ci2; tier A: standard phase name; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 1480–3999.74 K, x(Hf) 0.84811–1
Literature: 5 values (5 accepted) from 1 papers
Interactive: phase registry entry

Names (7): corpus: corpus:phase:co-hf:bcc-a2
paper: paper:10.1016/j.tca.2015.04.004:(βHf)
tdb: tdb:CoHf-06Bra.tdb:BCC_A2, tdb:CoHf-15Lu.tdb:A2_BCC, tdb:CoHf-15Lu.tdb:BCC_A2, tdb:CoHf-18Hua.tdb:A2_BCC, tdb:CoHf-18Hua.tdb:BCC_A2

TDB models of BCC_A2 (5): PHASE and CONSTITUENT statements as written

CoHf-06Bra.tdb: BCC_A2, type code %B, sha256 046d63a555f58b79…

34: PHASE BCC_A2 %B 2 1 3 !
35: CONST BCC_A2 : CO HF% : VA : !

CoHf-15Lu.tdb: A2_BCC, type code %B, sha256 dffa8495cab9319c…

40: PHASE A2_BCC %B 2 1 3 !
41: CONST A2_BCC : CO HF VA : VA : !

CoHf-15Lu.tdb: BCC_A2, type code %B, sha256 dffa8495cab9319c…

35: PHASE BCC_A2 %B 2 1 3 !
36: CONST BCC_A2 : CO HF% : VA : !

CoHf-18Hua.tdb: A2_BCC, type code %B, sha256 065a8d8f49f9e2c1…

37: PHASE A2_BCC %B 2 1 3 !
38: CONST A2_BCC : CO HF VA : VA : !

CoHf-18Hua.tdb: BCC_A2, type code %B, sha256 065a8d8f49f9e2c1…

32: PHASE BCC_A2 %B 2 1 3 !
33: CONST BCC_A2 : CO HF% : VA : !

Example references (4 of 4; assessments first):

doi:10.1016/j.tca.2015.04.004 Xingxu Lu, Shuhong Liu, Kaiming Cheng, Ying Tang, Pengfei Ou, Philip Nash et al., Thermodynamic modeling of the Co–Hf system supported by key experiments and first-principles calculations, Thermochimica Acta 608, 49-58 (2015).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.06.002 X.M. Huang, W.J. Zeng, J.L. Liu, G.M. Cai, S.H. Liu, H.S. Liu, Z.P. Jin, Calphad, 62, 128-40(2018).
assessment that models this phase
doi:10.1361/154770306X109746 J. Bratberg, B. Jansson, J. Phase Equilib. Diffus., 27, 213-19(2006).
assessment that models this phase
doi:10.1016/j.jallcom.2014.11.206 Xingxu Lu, Kaiming Cheng, Shuhong Liu, Kai Li, Feng Zheng, Yong Du, Experimental investigation of phase equilibria in the Co–Hf system, Journal of Alloys and Compounds 627, 251-260 (2015).
cited as the source of values for this phase

B2_BCC (Co–Hf)

Id: phase:co-hf:bcc-b2; status assigned
Structure: CsCl · B2 · cP2 · Pm-3m (221); type st:b2-cscl-cp2; tier A: standard phase name; confidence high
Caveat: CoHf-15Lu.tdb: ordered phase with disordered part A2_BCC (order/disorder model)
Caveat: CoHf-18Hua.tdb: ordered phase with disordered part A2_BCC (order/disorder model)
Caveat: partitioned order/disorder model in CoHf-15Lu.tdb also describes the disordered state
Caveat: partitioned order/disorder model in CoHf-18Hua.tdb also describes the disordered state
Stability: stable in 2 of 2 calculated diagram(s): 300–3531.03 K, x(Hf) 0.48209–1
Literature: 8 values (8 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:co-hf:bcc-b2, corpus:phase:co-hf:b2-bcc
paper: paper:10.1016/j.tca.2015.04.004:CoHf
tdb: tdb:CoHf-15Lu.tdb:B2_BCC, tdb:CoHf-18Hua.tdb:B2_BCC

TDB models of B2_BCC (2): PHASE and CONSTITUENT statements as written

CoHf-15Lu.tdb: B2_BCC, type code %BO, sha256 dffa8495cab9319c…

45: PHASE B2_BCC %BO 3 0.5 0.5 3 !
46: CONST B2_BCC : CO% HF VA : CO HF% VA : VA : !

CoHf-18Hua.tdb: B2_BCC, type code %BO, sha256 065a8d8f49f9e2c1…

42: PHASE B2_BCC %BO 3 0.5 0.5 3 !
43: CONST B2_BCC : CO% HF VA : CO HF% VA : VA : !

Example references (3 of 3; assessments first):

doi:10.1016/j.tca.2015.04.004 Xingxu Lu, Shuhong Liu, Kaiming Cheng, Ying Tang, Pengfei Ou, Philip Nash et al., Thermodynamic modeling of the Co–Hf system supported by key experiments and first-principles calculations, Thermochimica Acta 608, 49-58 (2015).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.06.002 X.M. Huang, W.J. Zeng, J.L. Liu, G.M. Cai, S.H. Liu, H.S. Liu, Z.P. Jin, Calphad, 62, 128-40(2018).
assessment that models this phase
doi:10.1016/j.jallcom.2014.11.206 Xingxu Lu, Kaiming Cheng, Shuhong Liu, Kai Li, Feng Zheng, Yong Du, Experimental investigation of phase equilibria in the Co–Hf system, Journal of Alloys and Compounds 627, 251-260 (2015).
cited as the source of values for this phase

C15_LAVES (Co–Hf)

Id: phase:co-hf:c15-laves; status assigned
Structure: Cu2Mg · C15 · cF24 · Fd-3m (227); type st:c15-cu2mg-cf24; tier A: standard phase name; confidence high
Caveat: partitioned order/disorder model in CoHf-15Lu.tdb also describes the disordered state
Caveat: partitioned order/disorder model in CoHf-18Hua.tdb also describes the disordered state
Stability: stable in 2 of 2 calculated diagram(s): 300–1895.96 K, x(Hf) 0.25028–0.34687
Literature: 20 values (20 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:co-hf:c15-laves
paper: paper:10.1016/j.tca.2015.04.004:Co2Hf
tdb: tdb:CoHf-15Lu.tdb:C15_LAVES, tdb:CoHf-18Hua.tdb:C15_LAVES

TDB models of C15_LAVES (2): PHASE and CONSTITUENT statements as written

CoHf-15Lu.tdb: C15_LAVES, type code %, sha256 dffa8495cab9319c…

65: PHASE C15_LAVES % 2 2 1 !
66: CONST C15_LAVES : CO% HF : CO HF% : !

CoHf-18Hua.tdb: C15_LAVES, type code %, sha256 065a8d8f49f9e2c1…

62: PHASE C15_LAVES % 2 2 1 !
63: CONST C15_LAVES : CO% HF : CO HF% : !

Example references (4 of 4; assessments first):

doi:10.1016/j.tca.2015.04.004 Xingxu Lu, Shuhong Liu, Kaiming Cheng, Ying Tang, Pengfei Ou, Philip Nash et al., Thermodynamic modeling of the Co–Hf system supported by key experiments and first-principles calculations, Thermochimica Acta 608, 49-58 (2015).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.06.002 X.M. Huang, W.J. Zeng, J.L. Liu, G.M. Cai, S.H. Liu, H.S. Liu, Z.P. Jin, Calphad, 62, 128-40(2018).
assessment that models this phase
doi:10.1016/0022-5088(78)90111-x K.H.J. Buschow, J.H. Wernick, G.Y. Chin, Note on the Hf-Co phase diagram, Journal of the Less Common Metals 59, 61-67 (1978).
cited as the source of values for this phase
doi:10.1016/j.jallcom.2014.11.206 Xingxu Lu, Kaiming Cheng, Shuhong Liu, Kai Li, Feng Zheng, Yong Du, Experimental investigation of phase equilibria in the Co–Hf system, Journal of Alloys and Compounds 627, 251-260 (2015).
cited as the source of values for this phase

CO11HF2 (Co–Hf)

Id: phase:co-hf:co11hf2; status needs_review
No structure assigned. Why: no_on_hull_entry_in_both; no_structure_token; sgte_mmc2_row_incomplete
Candidate (literature_printed): (Co11Hf2) · oP* — printed with a label mapped to this phase
Candidate (sgte_mmc2): (Co11Hf2) · Pban (50) — Hallstedt 2025 mmc2 row for CO11HF2: Co11Hf2
Stoichiometry: Co 0.8462, Hf 0.1538
Stability: stable in 2 of 2 calculated diagram(s): 928.48–1545.8 K, x(Hf) 0.15385–0.15385
Literature: 9 values (9 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:co-hf:co11hf2
paper: paper:10.1016/j.tca.2015.04.004:Co11Hf2
tdb: tdb:CoHf-15Lu.tdb:CO11HF2, tdb:CoHf-18Hua.tdb:CO11HF2

TDB models of CO11HF2 (2): PHASE and CONSTITUENT statements as written

CoHf-15Lu.tdb: CO11HF2, type code %, sha256 dffa8495cab9319c…

55: PHASE CO11HF2 % 2 11 2 !
56: CONST CO11HF2 : CO : HF : !

CoHf-18Hua.tdb: CO11HF2, type code %, sha256 065a8d8f49f9e2c1…

52: PHASE CO11HF2 % 2 11 2 !
53: CONST CO11HF2 : CO : HF : !

Example references (4 of 4; assessments first):

doi:10.1016/j.tca.2015.04.004 Xingxu Lu, Shuhong Liu, Kaiming Cheng, Ying Tang, Pengfei Ou, Philip Nash et al., Thermodynamic modeling of the Co–Hf system supported by key experiments and first-principles calculations, Thermochimica Acta 608, 49-58 (2015).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.06.002 X.M. Huang, W.J. Zeng, J.L. Liu, G.M. Cai, S.H. Liu, H.S. Liu, Z.P. Jin, Calphad, 62, 128-40(2018).
assessment that models this phase
doi:10.1016/j.jallcom.2014.11.206 Xingxu Lu, Kaiming Cheng, Shuhong Liu, Kai Li, Feng Zheng, Yong Du, Experimental investigation of phase equilibria in the Co–Hf system, Journal of Alloys and Compounds 627, 251-260 (2015).
cited as the source of values for this phase
doi:10.1016/0022-5088(78)90111-x K.H.J. Buschow, J.H. Wernick, G.Y. Chin, Note on the Hf-Co phase diagram, Journal of the Less Common Metals 59, 61-67 (1978).
cited as the source of values for this phase

CO23HF6_D8A (Co–Hf)

Id: phase:co-hf:co23hf6-d8a; status assigned
Structure: Mn23Th6 · D8_a · cF116 · Fm-3m (225); type st:d8-a-mn23th6-cf116; tier A: standard phase name; confidence high
Caveat: DFT agrees: on-hull mp-aaacpwmt and oqmd-29361, space group 225
Stoichiometry: Co 0.7931, Hf 0.2069
Stability: stable in 2 of 2 calculated diagram(s): 300–1600 K, x(Hf) 0.2069–0.2069
Literature: 11 values (11 accepted) from 1 papers
Interactive: phase registry entry

Names (6): corpus: corpus:phase:co-hf:co23hf6-d8a
mp: mp:mp-aaacpwmt
oqmd: oqmd:oqmd-29361
paper: paper:10.1016/j.tca.2015.04.004:Co23Hf6
tdb: tdb:CoHf-15Lu.tdb:CO23HF6_D8A, tdb:CoHf-18Hua.tdb:CO23HF6_D8A

TDB models of CO23HF6_D8A (2): PHASE and CONSTITUENT statements as written

CoHf-15Lu.tdb: CO23HF6_D8A, type code %, sha256 dffa8495cab9319c…

60: PHASE CO23HF6_D8A % 2 23 6 !
61: CONST CO23HF6_D8A : CO : HF : !

CoHf-18Hua.tdb: CO23HF6_D8A, type code %, sha256 065a8d8f49f9e2c1…

57: PHASE CO23HF6_D8A % 2 23 6 !
58: CONST CO23HF6_D8A : CO : HF : !

Example references (4 of 4; assessments first):

doi:10.1016/j.tca.2015.04.004 Xingxu Lu, Shuhong Liu, Kaiming Cheng, Ying Tang, Pengfei Ou, Philip Nash et al., Thermodynamic modeling of the Co–Hf system supported by key experiments and first-principles calculations, Thermochimica Acta 608, 49-58 (2015).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.06.002 X.M. Huang, W.J. Zeng, J.L. Liu, G.M. Cai, S.H. Liu, H.S. Liu, Z.P. Jin, Calphad, 62, 128-40(2018).
assessment that models this phase
doi:10.1016/j.jallcom.2014.11.206 Xingxu Lu, Kaiming Cheng, Shuhong Liu, Kai Li, Feng Zheng, Yong Du, Experimental investigation of phase equilibria in the Co–Hf system, Journal of Alloys and Compounds 627, 251-260 (2015).
cited as the source of values for this phase
doi:10.1016/0022-5088(78)90111-x K.H.J. Buschow, J.H. Wernick, G.Y. Chin, Note on the Hf-Co phase diagram, Journal of the Less Common Metals 59, 61-67 (1978).
cited as the source of values for this phase

CO2HF_C15 (Co–Hf)

Id: phase:co-hf:co2hf-c15; status assigned
Structure: Cu2Mg · C15 · cF24 · Fd-3m (227); type st:c15-cu2mg-cf24; tier A: standard phase name; confidence high
Stoichiometry: Co 0.6667, Hf 0.3333
Stability: stable in 1 of 1 calculated diagram(s): 300–2065.65 K, x(Hf) 0.33333–0.33333
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:co-hf:co2hf-c15
tdb: tdb:CoHf-06Bra.tdb:CO2HF_C15

TDB models of CO2HF_C15 (1): PHASE and CONSTITUENT statements as written

CoHf-06Bra.tdb: CO2HF_C15, type code %, sha256 046d63a555f58b79…

44: PHASE CO2HF_C15 % 2 2 1 !
45: CONST CO2HF_C15 : CO : HF : !

Example references (1 of 1; assessments first):

doi:10.1361/154770306X109746 J. Bratberg, B. Jansson, J. Phase Equilib. Diffus., 27, 213-19(2006).
assessment that models this phase

COHF_B2 (Co–Hf)

Id: phase:co-hf:cohf-b2; status needs_review
No structure assigned. Why: name_suggests_B2_but_dft_space_group_63
Candidate (dft_mp): Cmcm (63) — on-hull MP HfCo at x(HF)=0.5000
Candidate (dft_oqmd): Cmcm (63) — on-hull OQMD Co1 Hf1 at x(HF)=0.5000
Candidate (name_token): CsCl · B2 · cP2 · Pm-3m (221) — Strukturbericht/word 'B2' in the TDB name
Candidate (tdb_comment): CsCl · cP2 · Pm-3m — CoHf-06Bra.tdb: 'Prototype CsCl (cP2, Pm-3m)'
Stoichiometry: Co 0.5000, Hf 0.5000
Stability: stable in 1 of 1 calculated diagram(s): 300–2028.18 K, x(Hf) 0.5–0.5
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:co-hf:cohf-b2
tdb: tdb:CoHf-06Bra.tdb:COHF_B2

TDB models of COHF_B2 (1): PHASE and CONSTITUENT statements as written

CoHf-06Bra.tdb: COHF_B2, type code %, sha256 046d63a555f58b79…

49: PHASE COHF_B2 % 2 1 1 !
50: CONST COHF_B2 : CO : HF : !

Example references (1 of 1; assessments first):

doi:10.1361/154770306X109746 J. Bratberg, B. Jansson, J. Phase Equilib. Diffus., 27, 213-19(2006).
assessment that models this phase

COHF2 (Co–Hf)

Id: phase:co-hf:cohf2; status assigned
Structure: NiTi2 · cF96 · Fd-3m (227); type st:niti2-cf96; tier C: assessor-stated (Hallstedt 2025 crystallographic table); confidence assessor-stated
Structure source: B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, supplementary crystallographic table (mmc2) doi:10.1016/j.calphad.2025.102833
Caveat: not certain from the name or DFT alone (no_structure_token, off_stoichiometric_model); structure as stated in the SGTE crystallographic table for this phase name and system
Stability: stable in 3 of 3 calculated diagram(s): 300–1699.29 K, x(Hf) 0.65937–0.68042
Literature: 20 values (20 accepted) from 2 papers
Interactive: phase registry entry

Names (6): corpus: corpus:phase:co-hf:cohf2
paper: paper:10.1016/j.tca.2015.04.004:CoHf2, paper:10.1361/154770306x109746:CoHf2
tdb: tdb:CoHf-06Bra.tdb:COHF2, tdb:CoHf-15Lu.tdb:COHF2, tdb:CoHf-18Hua.tdb:COHF2

TDB models of COHF2 (3): PHASE and CONSTITUENT statements as written

CoHf-06Bra.tdb: COHF2, type code %, sha256 046d63a555f58b79…

54: PHASE COHF2 % 2 1 2 !
55: CONST COHF2 : CO : HF : !

CoHf-15Lu.tdb: COHF2, type code %, sha256 dffa8495cab9319c…

70: PHASE COHF2 % 2 1 2 !
71: CONST COHF2 : CO% HF : CO HF% : !

CoHf-18Hua.tdb: COHF2, type code %, sha256 065a8d8f49f9e2c1…

67: PHASE COHF2 % 2 1 2 !
68: CONST COHF2 : CO% HF : CO HF% : !

Example references (4 of 4; assessments first):

doi:10.1016/j.tca.2015.04.004 Xingxu Lu, Shuhong Liu, Kaiming Cheng, Ying Tang, Pengfei Ou, Philip Nash et al., Thermodynamic modeling of the Co–Hf system supported by key experiments and first-principles calculations, Thermochimica Acta 608, 49-58 (2015).
assessment that models this phase; reports values for this phase
doi:10.1361/154770306X109746 J. Bratberg, B. Jansson, J. Phase Equilib. Diffus., 27, 213-19(2006).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.06.002 X.M. Huang, W.J. Zeng, J.L. Liu, G.M. Cai, S.H. Liu, H.S. Liu, Z.P. Jin, Calphad, 62, 128-40(2018).
assessment that models this phase
doi:10.1016/j.jallcom.2014.11.206 Xingxu Lu, Kaiming Cheng, Shuhong Liu, Kai Li, Feng Zheng, Yong Du, Experimental investigation of phase equilibria in the Co–Hf system, Journal of Alloys and Compounds 627, 251-260 (2015).
cited as the source of values for this phase

FCC_A1 (Co–Hf)

Id: phase:co-hf:fcc-a1; status assigned
Structure: Cu · A1 · cF4 · Fm-3m (225); type st:a1-cu-cf4; tier A: standard phase name; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 694.96–1773.17 K, x(Hf) 0–0.01466
Literature: 8 values (8 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:co-hf:fcc-a1
paper: paper:10.1016/j.tca.2015.04.004:(αCo)
tdb: tdb:CoHf-06Bra.tdb:FCC_A1, tdb:CoHf-15Lu.tdb:FCC_A1, tdb:CoHf-18Hua.tdb:FCC_A1

TDB models of FCC_A1 (3): PHASE and CONSTITUENT statements as written

CoHf-06Bra.tdb: FCC_A1, type code %A, sha256 046d63a555f58b79…

29: PHASE FCC_A1 %A 2 1 1 !
30: CONST FCC_A1 : CO% HF : VA : !

CoHf-15Lu.tdb: FCC_A1, type code %A, sha256 dffa8495cab9319c…

30: PHASE FCC_A1 %A 2 1 1 !
31: CONST FCC_A1 : CO% HF : VA : !

CoHf-18Hua.tdb: FCC_A1, type code %A, sha256 065a8d8f49f9e2c1…

27: PHASE FCC_A1 %A 2 1 1 !
28: CONST FCC_A1 : CO% HF : VA : !

Example references (5 of 5; assessments first):

doi:10.1016/j.tca.2015.04.004 Xingxu Lu, Shuhong Liu, Kaiming Cheng, Ying Tang, Pengfei Ou, Philip Nash et al., Thermodynamic modeling of the Co–Hf system supported by key experiments and first-principles calculations, Thermochimica Acta 608, 49-58 (2015).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.06.002 X.M. Huang, W.J. Zeng, J.L. Liu, G.M. Cai, S.H. Liu, H.S. Liu, Z.P. Jin, Calphad, 62, 128-40(2018).
assessment that models this phase
doi:10.1361/154770306X109746 J. Bratberg, B. Jansson, J. Phase Equilib. Diffus., 27, 213-19(2006).
assessment that models this phase
doi:10.1016/j.jallcom.2014.11.206 Xingxu Lu, Kaiming Cheng, Shuhong Liu, Kai Li, Feng Zheng, Yong Du, Experimental investigation of phase equilibria in the Co–Hf system, Journal of Alloys and Compounds 627, 251-260 (2015).
cited as the source of values for this phase
doi:10.1016/0022-5088(78)90111-x K.H.J. Buschow, J.H. Wernick, G.Y. Chin, Note on the Hf-Co phase diagram, Journal of the Less Common Metals 59, 61-67 (1978).
cited as the source of values for this phase

HCP_A3 (Co–Hf)

Id: phase:co-hf:hcp-a3; status assigned
Structure: Mg · A3 · hP2 · P6_3/mmc (194); type st:a3-mg-hp2; tier A: standard phase name; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 300–2500.33 K, x(Hf) 0–1
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (6): corpus: corpus:phase:co-hf:hcp-a3
paper: paper:10.1016/j.tca.2015.04.004:(αHf), paper:10.1016/j.tca.2015.04.004:(εCo)
tdb: tdb:CoHf-06Bra.tdb:HCP_A3, tdb:CoHf-15Lu.tdb:HCP_A3, tdb:CoHf-18Hua.tdb:HCP_A3

TDB models of HCP_A3 (3): PHASE and CONSTITUENT statements as written

CoHf-06Bra.tdb: HCP_A3, type code %A, sha256 046d63a555f58b79…

39: PHASE HCP_A3 %A 2 1 0.5 !
40: CONST HCP_A3 : CO% HF% : VA : !

CoHf-15Lu.tdb: HCP_A3, type code %A, sha256 dffa8495cab9319c…

50: PHASE HCP_A3 %A 2 1 0.5 !
51: CONST HCP_A3 : CO% HF% : VA : !

CoHf-18Hua.tdb: HCP_A3, type code %A, sha256 065a8d8f49f9e2c1…

47: PHASE HCP_A3 %A 2 1 0.5 !
48: CONST HCP_A3 : CO% HF% : VA : !

Example references (3 of 3; assessments first):

doi:10.1016/j.tca.2015.04.004 Xingxu Lu, Shuhong Liu, Kaiming Cheng, Ying Tang, Pengfei Ou, Philip Nash et al., Thermodynamic modeling of the Co–Hf system supported by key experiments and first-principles calculations, Thermochimica Acta 608, 49-58 (2015).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.06.002 X.M. Huang, W.J. Zeng, J.L. Liu, G.M. Cai, S.H. Liu, H.S. Liu, Z.P. Jin, Calphad, 62, 128-40(2018).
assessment that models this phase
doi:10.1361/154770306X109746 J. Bratberg, B. Jansson, J. Phase Equilib. Diffus., 27, 213-19(2006).
assessment that models this phase

LIQUID (Co–Hf)

Id: phase:co-hf:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 1516.31–4000 K, x(Hf) 0–1
Literature: 25 values (25 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:co-hf:liquid
paper: paper:10.1016/j.tca.2015.04.004:Liquid
tdb: tdb:CoHf-06Bra.tdb:LIQUID, tdb:CoHf-15Lu.tdb:LIQUID, tdb:CoHf-18Hua.tdb:LIQUID

TDB models of LIQUID (3): PHASE and CONSTITUENT statements as written

CoHf-06Bra.tdb: LIQUID, type code %, sha256 046d63a555f58b79…

24: PHASE LIQUID:L % 1 1 !
25: CONST LIQUID:L : CO HF : !

CoHf-15Lu.tdb: LIQUID, type code %, sha256 dffa8495cab9319c…

25: PHASE LIQUID:L % 1 1 !
26: CONST LIQUID:L : CO HF : !

CoHf-18Hua.tdb: LIQUID, type code %, sha256 065a8d8f49f9e2c1…

22: PHASE LIQUID:L % 1 1 !
23: CONST LIQUID:L : CO HF : !

Example references (5 of 5; assessments first):

doi:10.1016/j.tca.2015.04.004 Xingxu Lu, Shuhong Liu, Kaiming Cheng, Ying Tang, Pengfei Ou, Philip Nash et al., Thermodynamic modeling of the Co–Hf system supported by key experiments and first-principles calculations, Thermochimica Acta 608, 49-58 (2015).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.06.002 X.M. Huang, W.J. Zeng, J.L. Liu, G.M. Cai, S.H. Liu, H.S. Liu, Z.P. Jin, Calphad, 62, 128-40(2018).
assessment that models this phase
doi:10.1361/154770306X109746 J. Bratberg, B. Jansson, J. Phase Equilib. Diffus., 27, 213-19(2006).
assessment that models this phase
doi:10.1016/j.jallcom.2014.11.206 Xingxu Lu, Kaiming Cheng, Shuhong Liu, Kai Li, Feng Zheng, Yong Du, Experimental investigation of phase equilibria in the Co–Hf system, Journal of Alloys and Compounds 627, 251-260 (2015).
cited as the source of values for this phase
doi:10.1016/0022-5088(78)90111-x K.H.J. Buschow, J.H. Wernick, G.Y. Chin, Note on the Hf-Co phase diagram, Journal of the Less Common Metals 59, 61-67 (1978).
cited as the source of values for this phase

Please cite

R. Arróyave, J. Saal, D. Shin, ORCHID-Registry: phase registry of binary systems (version 2026.10; Version 1, machine-extracted), Zenodo (2026). doi:10.5281/zenodo.23735970
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 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); the original source of every value you use (paper_citation / paper_doi, and cited_dois for values the paper cites from earlier work). 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_phase_registry_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Registry: phase registry of binary systems}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735970},
  url       = {https://doi.org/10.5281/zenodo.23735970},
  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}
}