Al–N phases

9 phases (tier A 5, liquid 2, gas 2); 6 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 · Al–N system page · Markdown · field reference

Phases of the Al–N system (9)
Phase	Structure	Basis	Stability (calculated)	TDB models
ALN_B3 phase:al-n:aln-b3	ZnS (sphalerite) · B3 · cF8 · F-43m (216)	tier A: standard phase name	not stable in 1 calculated diagram(s)	1
ALN_B4 phase:al-n:aln-b4	ZnS (wurtzite) · B4 · hP4 · P6_3mc (186)	tier A: standard phase name	stable in 4 of 4 calculated diagram(s): 300–2500 K, x(N) 0.5–0.5	4
BCC_A2 phase:al-n:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	not stable in 4 calculated diagram(s)	4
FCC_A1 phase:al-n:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 4 of 4 calculated diagram(s): 300–962.34 K, x(N) 0–5e-05	4
GAS phase:al-n:gas	gas	gas	stable in 4 of 4 calculated diagram(s): 300–2500 K, x(N) 0.98019–1	4
HCP_A3 phase:al-n:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	not stable in 4 calculated diagram(s)	4
ION phase:al-n:ion	liquid	liquid	stable in 3 of 3 calculated diagram(s): 933.34–2500 K, x(N) 0–0.0049	3
LIQUID phase:al-n:liquid	liquid	liquid	stable in 2 of 2 calculated diagram(s): 933.31–2500 K, x(N) 0–0.00148	2
N2GAS phase:al-n:n2gas	gas	gas	stable in 3 of 4 calculated diagram(s): 300–1715 K, x(N) 1–1	4

ALN_B3 (Al–N)

Id: phase:al-n:aln-b3; status assigned
Structure: ZnS (sphalerite) · B3 · cF8 · F-43m (216); type st:b3-zns-sphalerite-cf8; tier A: standard phase name; confidence high
Stoichiometry: Al 0.5000, N 0.5000
Stability: not stable in 1 calculated diagram(s)
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:al-n:aln-b3
tdb: tdb:AlN-19Sri.tdb:ALN_B3

TDB models of ALN_B3 (1): PHASE and CONSTITUENT statements as written

AlN-19Sri.tdb: ALN_B3, type code %, sha256 5663a4eb05e34e21…

62: PHASE ALN_B3 % 2 1 1 !
63: CONST ALN_B3 : AL : N : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2019.03.008 S. Sridar, R. Kumar, K.C. Hari Kumar, Calphad, 65, 298-98(2019).
assessment that models this phase

ALN_B4 (Al–N)

Id: phase:al-n:aln-b4; status assigned
Structure: ZnS (wurtzite) · B4 · hP4 · P6_3mc (186); type st:b4-zns-wurtzite-hp4; tier A: standard phase name; confidence high
Stability: stable in 4 of 4 calculated diagram(s): 300–2500 K, x(N) 0.5–0.5
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:al-n:aln-b4
tdb: tdb:AlN-12Pav.tdb:ALN_B4, tdb:AlN-19Sri.tdb:ALN_B4, tdb:AlN-92Hil.tdb:ALN_B4, tdb:AlN-98Luk-LB.tdb:ALN_B4

TDB models of ALN_B4 (4): PHASE and CONSTITUENT statements as written

AlN-12Pav.tdb: ALN_B4, type code %, sha256 b71f53ed66e8ec4d…

75: PHASE ALN_B4:I % 2 2 2 !
76: CONST ALN_B4:I : AL+3 : N-3 : !

AlN-19Sri.tdb: ALN_B4, type code %, sha256 5663a4eb05e34e21…

57: PHASE ALN_B4 % 2 1 1 !
58: CONST ALN_B4 : AL : N : !

AlN-92Hil.tdb: ALN_B4, type code %, sha256 982fcadf622909c3…

71: PHASE ALN_B4 % 2 1 1 !
72: CONST ALN_B4 : AL : N : !

AlN-98Luk-LB.tdb: ALN_B4, type code %, sha256 ffaef9c6915723a0…

49: PHASE ALN_B4 % 2 1 1 !
50: CONST ALN_B4 : AL : N : !

Example references (3 of 3; assessments first):

doi:10.1007/BF02646133 M. Hillert, S. Jonsson, Metall. Trans. A, 23A, 3141-49(1992).
assessment that models this phase
doi:10.1007/s11669-012-0073-5 D. Pavlyuchkov, O. Fabrichnaya, M. Herrmann, H. J. Seifert, Thermodynamic Assessments of the Al2O3-Al4C3-AlN and Al4C3-AlN-SiC Systems, J. Phase Equilib. Diffus. 33, 357-368 (2012).
assessment that models this phase
doi:10.1016/j.calphad.2019.03.008 S. Sridar, R. Kumar, K.C. Hari Kumar, Calphad, 65, 298-98(2019).
assessment that models this phase

BCC_A2 (Al–N)

Id: phase:al-n:bcc-a2; status assigned
Structure: W · A2 · cI2 · Im-3m (229); type st:a2-w-ci2; tier A: standard phase name; confidence high
Stability: not stable in 4 calculated diagram(s)
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:al-n:bcc-a2
tdb: tdb:AlN-12Pav.tdb:BCC_A2, tdb:AlN-19Sri.tdb:BCC_A2, tdb:AlN-92Hil.tdb:BCC_A2, tdb:AlN-98Luk-LB.tdb:BCC_A2

TDB models of BCC_A2 (4): PHASE and CONSTITUENT statements as written

AlN-12Pav.tdb: BCC_A2, type code %B, sha256 b71f53ed66e8ec4d…

64: PHASE BCC_A2 %B 2 1 3 !
65: CONST BCC_A2 : AL : N VA% : !

AlN-19Sri.tdb: BCC_A2, type code %B, sha256 5663a4eb05e34e21…

47: PHASE BCC_A2 %B 2 1 3 !
48: CONST BCC_A2 : AL : N VA% : !

AlN-92Hil.tdb: BCC_A2, type code %B, sha256 982fcadf622909c3…

61: PHASE BCC_A2 %B 2 1 3 !
62: CONST BCC_A2 : AL : VA% N : !

AlN-98Luk-LB.tdb: BCC_A2, type code %B, sha256 ffaef9c6915723a0…

39: PHASE BCC_A2 %B 2 1 3 !
40: CONST BCC_A2 : AL : VA% N : !

Example references (3 of 3; assessments first):

doi:10.1007/BF02646133 M. Hillert, S. Jonsson, Metall. Trans. A, 23A, 3141-49(1992).
assessment that models this phase
doi:10.1007/s11669-012-0073-5 D. Pavlyuchkov, O. Fabrichnaya, M. Herrmann, H. J. Seifert, Thermodynamic Assessments of the Al2O3-Al4C3-AlN and Al4C3-AlN-SiC Systems, J. Phase Equilib. Diffus. 33, 357-368 (2012).
assessment that models this phase
doi:10.1016/j.calphad.2019.03.008 S. Sridar, R. Kumar, K.C. Hari Kumar, Calphad, 65, 298-98(2019).
assessment that models this phase

FCC_A1 (Al–N)

Id: phase:al-n: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 4 of 4 calculated diagram(s): 300–962.34 K, x(N) 0–5e-05
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:al-n:fcc-a1
tdb: tdb:AlN-12Pav.tdb:FCC_A1, tdb:AlN-19Sri.tdb:FCC_A1, tdb:AlN-92Hil.tdb:FCC_A1, tdb:AlN-98Luk-LB.tdb:FCC_A1

TDB models of FCC_A1 (4): PHASE and CONSTITUENT statements as written

AlN-12Pav.tdb: FCC_A1, type code %A, sha256 b71f53ed66e8ec4d…

59: PHASE FCC_A1 %A 2 1 1 !
60: CONST FCC_A1 : AL : N VA% : !

AlN-19Sri.tdb: FCC_A1, type code %A, sha256 5663a4eb05e34e21…

42: PHASE FCC_A1 %A 2 1 1 !
43: CONST FCC_A1 : AL : N VA% : !

AlN-92Hil.tdb: FCC_A1, type code %A, sha256 982fcadf622909c3…

56: PHASE FCC_A1 %A 2 1 1 !
57: CONST FCC_A1 : AL% : N VA% : !

AlN-98Luk-LB.tdb: FCC_A1, type code %A, sha256 ffaef9c6915723a0…

34: PHASE FCC_A1 %A 2 1 1 !
35: CONST FCC_A1 : AL% : N VA% : !

Example references (3 of 3; assessments first):

doi:10.1007/BF02646133 M. Hillert, S. Jonsson, Metall. Trans. A, 23A, 3141-49(1992).
assessment that models this phase
doi:10.1007/s11669-012-0073-5 D. Pavlyuchkov, O. Fabrichnaya, M. Herrmann, H. J. Seifert, Thermodynamic Assessments of the Al2O3-Al4C3-AlN and Al4C3-AlN-SiC Systems, J. Phase Equilib. Diffus. 33, 357-368 (2012).
assessment that models this phase
doi:10.1016/j.calphad.2019.03.008 S. Sridar, R. Kumar, K.C. Hari Kumar, Calphad, 65, 298-98(2019).
assessment that models this phase

GAS (Al–N)

Id: phase:al-n:gas; status assigned
Structure: gas; type st:gas; gas; confidence high
Stability: stable in 4 of 4 calculated diagram(s): 300–2500 K, x(N) 0.98019–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:al-n:gas
tdb: tdb:AlN-12Pav.tdb:GAS, tdb:AlN-19Sri.tdb:GAS, tdb:AlN-92Hil.tdb:GAS, tdb:AlN-98Luk-LB.tdb:GAS

TDB models of GAS (4): PHASE and CONSTITUENT statements as written

AlN-12Pav.tdb: GAS, type code %, sha256 b71f53ed66e8ec4d…

78: PHASE GAS:G % 1 1 !
79: CONST GAS:G : AL% AL2 ALN N N2 N3 : !

AlN-19Sri.tdb: GAS, type code %, sha256 5663a4eb05e34e21…

65: PHASE GAS:G % 1 1 !
66: CONST GAS:G : AL% AL2 ALN N N2 N3 : !

AlN-92Hil.tdb: GAS, type code %, sha256 982fcadf622909c3…

77: PHASE GAS:G % 1 1 !
78: CONST GAS:G : AL AL2 ALN N N2 N3 : !

AlN-98Luk-LB.tdb: GAS, type code %, sha256 ffaef9c6915723a0…

55: PHASE GAS:G % 1 1 !
56: CONST GAS:G : AL AL2 ALN N N2 N3 : !

Example references (3 of 3; assessments first):

doi:10.1007/BF02646133 M. Hillert, S. Jonsson, Metall. Trans. A, 23A, 3141-49(1992).
assessment that models this phase
doi:10.1007/s11669-012-0073-5 D. Pavlyuchkov, O. Fabrichnaya, M. Herrmann, H. J. Seifert, Thermodynamic Assessments of the Al2O3-Al4C3-AlN and Al4C3-AlN-SiC Systems, J. Phase Equilib. Diffus. 33, 357-368 (2012).
assessment that models this phase
doi:10.1016/j.calphad.2019.03.008 S. Sridar, R. Kumar, K.C. Hari Kumar, Calphad, 65, 298-98(2019).
assessment that models this phase

HCP_A3 (Al–N)

Id: phase:al-n: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: not stable in 4 calculated diagram(s)
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:al-n:hcp-a3
tdb: tdb:AlN-12Pav.tdb:HCP_A3, tdb:AlN-19Sri.tdb:HCP_A3, tdb:AlN-92Hil.tdb:HCP_A3, tdb:AlN-98Luk-LB.tdb:HCP_A3

TDB models of HCP_A3 (4): PHASE and CONSTITUENT statements as written

AlN-12Pav.tdb: HCP_A3, type code %A, sha256 b71f53ed66e8ec4d…

69: PHASE HCP_A3 %A 2 1 0.5 !
70: CONST HCP_A3 : AL : N VA% : !

AlN-19Sri.tdb: HCP_A3, type code %A, sha256 5663a4eb05e34e21…

52: PHASE HCP_A3 %A 2 1 0.5 !
53: CONST HCP_A3 : AL : N VA% : !

AlN-92Hil.tdb: HCP_A3, type code %, sha256 982fcadf622909c3…

66: PHASE HCP_A3 % 2 1 0.5 !
67: CONST HCP_A3 : AL : VA% N : !

AlN-98Luk-LB.tdb: HCP_A3, type code %, sha256 ffaef9c6915723a0…

44: PHASE HCP_A3 % 2 1 0.5 !
45: CONST HCP_A3 : AL : VA% N : !

Example references (3 of 3; assessments first):

doi:10.1007/BF02646133 M. Hillert, S. Jonsson, Metall. Trans. A, 23A, 3141-49(1992).
assessment that models this phase
doi:10.1007/s11669-012-0073-5 D. Pavlyuchkov, O. Fabrichnaya, M. Herrmann, H. J. Seifert, Thermodynamic Assessments of the Al2O3-Al4C3-AlN and Al4C3-AlN-SiC Systems, J. Phase Equilib. Diffus. 33, 357-368 (2012).
assessment that models this phase
doi:10.1016/j.calphad.2019.03.008 S. Sridar, R. Kumar, K.C. Hari Kumar, Calphad, 65, 298-98(2019).
assessment that models this phase

ION (Al–N)

Id: phase:al-n:ion; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 933.34–2500 K, x(N) 0–0.0049
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:al-n:ion
tdb: tdb:AlN-12Pav.tdb:ION, tdb:AlN-19Sri.tdb:ION, tdb:AlN-92Hil.tdb:ION

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

AlN-12Pav.tdb: ION, type code %, sha256 b71f53ed66e8ec4d…

54: PHASE ION:Y % 2 1 1 !
55: CONST ION:Y : AL+3 : VA ALN N : !

AlN-19Sri.tdb: ION, type code %, sha256 5663a4eb05e34e21…

37: PHASE ION:Y % 2 1 1 !
38: CONST ION:Y : AL+3 : VA ALN N : !

AlN-92Hil.tdb: ION, type code %, sha256 982fcadf622909c3…

51: PHASE ION:Y % 2 1 1 !
52: CONST ION:Y : AL+3 : N-3 VA N : !

Example references (3 of 3; assessments first):

doi:10.1007/BF02646133 M. Hillert, S. Jonsson, Metall. Trans. A, 23A, 3141-49(1992).
assessment that models this phase
doi:10.1007/s11669-012-0073-5 D. Pavlyuchkov, O. Fabrichnaya, M. Herrmann, H. J. Seifert, Thermodynamic Assessments of the Al2O3-Al4C3-AlN and Al4C3-AlN-SiC Systems, J. Phase Equilib. Diffus. 33, 357-368 (2012).
assessment that models this phase
doi:10.1016/j.calphad.2019.03.008 S. Sridar, R. Kumar, K.C. Hari Kumar, Calphad, 65, 298-98(2019).
assessment that models this phase

LIQUID (Al–N)

Id: phase:al-n:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 2 of 2 calculated diagram(s): 933.31–2500 K, x(N) 0–0.00148
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:al-n:liquid
tdb: tdb:AlN-92Hil.tdb:LIQUID, tdb:AlN-98Luk-LB.tdb:LIQUID

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

AlN-92Hil.tdb: LIQUID, type code %, sha256 982fcadf622909c3…

48: PHASE LIQUID:L % 1 1 !
49: CONST LIQUID:L : AL ALN N : !

AlN-98Luk-LB.tdb: LIQUID, type code %, sha256 ffaef9c6915723a0…

29: PHASE LIQUID:L % 1 1 !
30: CONST LIQUID:L : AL N : !

Example references (1 of 1; assessments first):

doi:10.1007/BF02646133 M. Hillert, S. Jonsson, Metall. Trans. A, 23A, 3141-49(1992).
assessment that models this phase

N2GAS (Al–N)

Id: phase:al-n:n2gas; status assigned
Structure: gas; type st:gas; gas; confidence high
Stability: stable in 3 of 4 calculated diagram(s): 300–1715 K, x(N) 1–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:al-n:n2gas
tdb: tdb:AlN-12Pav.tdb:N2GAS, tdb:AlN-19Sri.tdb:N2GAS, tdb:AlN-92Hil.tdb:N2GAS, tdb:AlN-98Luk-LB.tdb:N2GAS

TDB models of N2GAS (4): PHASE and CONSTITUENT statements as written

AlN-12Pav.tdb: N2GAS, type code %, sha256 b71f53ed66e8ec4d…

81: PHASE N2GAS % 1 1 !
82: CONST N2GAS : N2 : !

AlN-19Sri.tdb: N2GAS, type code %, sha256 5663a4eb05e34e21…

68: PHASE N2GAS % 1 1 !
69: CONST N2GAS : N2 : !

AlN-92Hil.tdb: N2GAS, type code %, sha256 982fcadf622909c3…

74: PHASE N2GAS % 1 1 !
75: CONST N2GAS : N2 : !

AlN-98Luk-LB.tdb: N2GAS, type code %, sha256 ffaef9c6915723a0…

52: PHASE N2GAS % 1 1 !
53: CONST N2GAS : N2 : !

Example references (3 of 3; assessments first):

doi:10.1007/BF02646133 M. Hillert, S. Jonsson, Metall. Trans. A, 23A, 3141-49(1992).
assessment that models this phase
doi:10.1007/s11669-012-0073-5 D. Pavlyuchkov, O. Fabrichnaya, M. Herrmann, H. J. Seifert, Thermodynamic Assessments of the Al2O3-Al4C3-AlN and Al4C3-AlN-SiC Systems, J. Phase Equilib. Diffus. 33, 357-368 (2012).
assessment that models this phase
doi:10.1016/j.calphad.2019.03.008 S. Sridar, R. Kumar, K.C. Hari Kumar, Calphad, 65, 298-98(2019).
assessment that models 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}
}