Si–W system

78 accepted literature values from 3 paper(s) (experimental 58, model 20); 4 calculated phase diagram(s). 3 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 (7) · papers (bibliography) · Markdown

Accepted values by evidence class
Evidence classValues
experimental58
model20
Accepted values by property group
Property groupValues
invariant reaction39
phase transition24
formation11
crystal structure4

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 fileAssessmentSHA-256Links
SiW-03Che-LB.tdbP.-Y. Chevalier, E. Fischer, unpublished, 2003.980d470108b9356014b6a28aedaff9d818a3785bf4b9d86044bce6c3fb688023viewer · TDB · JSON
SiW-09Guo.tdbZ. Guo, W. Yuan, Y. Sun, Z. Cai, Z. Qiao, J. Phase Equilib. Diffus., 30, 564-70(2009). doi:10.1007/s11669-009-9579-x5f6d911f9b50695896885bab52759251967d3aeb5536938d44554d602e33a85fviewer · TDB · JSON
SiW-13Li.tdbY. Li, C. Li, Z. Du, C. Guo, Calphad, 43, 112-23(2013). doi:10.1016/j.calphad.2013.04.0046cb14cc0019fd85687d871a41d2eadee3ed10a9f84d075558c911dca731f1d55viewer · TDB · JSON
SiW-89Vah.tdbC. Vahlas, P.-Y. Chevalier, E. Blanquet, Calphad, 13, 273-92(1989). doi:10.1016/0364-5916(89)90007-21b97c566f7b1735ce36c841c697dde9e201aeb64f8c5c00322f49c792b83ab23viewer · TDB · JSON
Calculated three-phase invariants (model, mole fraction of the second component)
TDB fileT (K)Phases at the invariant
SiW-03Che-LB.tdb2535.87SI3W5_D8M (x(W) 0.625) + LIQUID (x(W) 0.65046) + BCC_A2 (x(W) 0.93612)
SiW-03Che-LB.tdb2535.87SI3W5_D8M (x(W) 0.625) + LIQUID (x(W) 0.65049) + BCC_A2 (x(W) 0.93613)
SiW-03Che-LB.tdb2301.46SI2W_C11B (x(W) 0.33333) + LIQUID (x(W) 0.4442) + SI3W5_D8M (x(W) 0.625)
SiW-03Che-LB.tdb2301.46SI2W_C11B (x(W) 0.33333) + LIQUID (x(W) 0.44445) + SI3W5_D8M (x(W) 0.625)
SiW-03Che-LB.tdb1671.14DIAMOND_A4 (x(W) 0) + LIQUID (x(W) 0.02879) + SI2W_C11B (x(W) 0.33333)
SiW-03Che-LB.tdb1671.13DIAMOND_A4 (x(W) 0) + LIQUID (x(W) 0.02842) + SI2W_C11B (x(W) 0.33333)
SiW-09Guo.tdb2484.59SI3W5_D8M (x(W) 0.625) + LIQUID (x(W) 0.71224) + BCC_A2 (x(W) 0.94521)
SiW-09Guo.tdb2484.59SI3W5_D8M (x(W) 0.625) + LIQUID (x(W) 0.71226) + BCC_A2 (x(W) 0.94522)
SiW-09Guo.tdb2284.02SI2W_C11B (x(W) 0.33333) + LIQUID (x(W) 0.46847) + SI3W5_D8M (x(W) 0.625)
SiW-09Guo.tdb2284.02SI2W_C11B (x(W) 0.33333) + LIQUID (x(W) 0.46856) + SI3W5_D8M (x(W) 0.625)
SiW-09Guo.tdb1660.94DIAMOND_A4 (x(W) 0) + LIQUID (x(W) 0.04416) + SI2W_C11B (x(W) 0.33333)
SiW-09Guo.tdb1660.93DIAMOND_A4 (x(W) 0) + LIQUID (x(W) 0.0438) + SI2W_C11B (x(W) 0.33333)
SiW-13Li.tdb2352.03SI3W5_D8M (x(W) 0.6217) + LIQUID (x(W) 0.66752) + BCC_A2 (x(W) 0.96066)
SiW-13Li.tdb2230.71SI2W_C11B (x(W) 0.33333) + LIQUID (x(W) 0.46164) + SI3W5_D8M (x(W) 0.59955)
SiW-13Li.tdb1666.92DIAMOND_A4 (x(W) 0) + LIQUID (x(W) 0.03509) + SI2W_C11B (x(W) 0.33333)
SiW-13Li.tdb1666.92DIAMOND_A4 (x(W) 0) + LIQUID (x(W) 0.03487) + SI2W_C11B (x(W) 0.33333)
SiW-89Vah.tdb2353.53SI3W5_D8M (x(W) 0.625) + LIQUID (x(W) 0.6687) + BCC_A2 (x(W) 0.96946)
SiW-89Vah.tdb2353.53SI3W5_D8M (x(W) 0.625) + LIQUID (x(W) 0.66872) + BCC_A2 (x(W) 0.96946)
SiW-89Vah.tdb2213.37SI2W_C11B (x(W) 0.33333) + LIQUID (x(W) 0.47439) + SI3W5_D8M (x(W) 0.625)
SiW-89Vah.tdb2213.37SI2W_C11B (x(W) 0.33333) + LIQUID (x(W) 0.47441) + SI3W5_D8M (x(W) 0.625)
SiW-89Vah.tdb1662.09DIAMOND_A4 (x(W) 0) + LIQUID (x(W) 0.04134) + SI2W_C11B (x(W) 0.33333)
SiW-89Vah.tdb1662.09DIAMOND_A4 (x(W) 0) + LIQUID (x(W) 0.04132) + SI2W_C11B (x(W) 0.33333)

Convex hulls: Materials Project DFT hull · OQMD DFT hull · CALPHAD hull SiW-03Che-LB · CALPHAD hull SiW-09Guo · CALPHAD hull SiW-89Vah

Invariant reactions (literature)

Invariant reactions reported in the literature for the Si–W system (39)
T (K)Reaction / phasesCompositions (mole fraction)ClassSourceLocationQuote
2643(L)+bcc->Si3W5L: W 0.58; bcc: W 0.92; Si3W5: W 0.625experimental[1] Vahlas 1989
cites ref. 58
Table 8, p. 15, row 28
report
2594congruent melting: L <-> W5Si3W5Si3: Si 0.375model[2] Guo 2009Table 5, p. 5, row 4
report
2593congruent melting: L <-> W5Si3W5Si3: Si 0.375experimental[2] Guo 2009
cites Maksimov 1969
Table 5, p. 5, row 5
report
2523eutectic: (L)->Si3W5+bccL: W 0.8; Si3W5: W 0.625; bcc: W 0.95experimental[1] Vahlas 1989
cites ref. 18
Table 8, p. 15, row 30
report
2483eutectic: (L)->Si3W5+bccL: W 0.79; Si3W5: W 0.625; bcc: W 0.94experimental[1] Vahlas 1989
cites ref. 48
Table 8, p. 15, row 31
report
2460L <-> (W) + W5Si3L: Si 0.281; (W): Si 0.055; W5Si3: Si 0.375model[2] Guo 2009Table 5, p. 5, row 1
report
2453eutectic: L->Bcc+W5Si3W5Si3: W 0.625experimental[3] Li 2013
cites Maksimov 1969
Table 2, p. 3, row 3
report
2453eutectic: (L)->Si3W5+bccL: W 0.68; Si3W5: W 0.625; bcc: W 0.95experimental[1] Vahlas 1989
cites ref. 49
Table 8, p. 15, row 32
report
2453L <-> (W) + W5Si3L: Si 0.315; (W): Si 0.055; W5Si3: Si 0.375experimental[2] Guo 2009
cites Maksimov 1969
Table 5, p. 5, row 2
report
2433congruent melting: L <-> WSi2WSi2: Si 0.667model[2] Guo 2009Table 5, p. 5, row 10
report
2433congruent melting: L <-> WSi2WSi2: Si 0.667experimental[2] Guo 2009
cites Maksimov 1969
Table 5, p. 5, row 11
report
2368congruent melting: L <-> W5Si3W5Si3: Si 0.375experimental[2] Guo 2009
cites Yu 1973
Table 5, p. 5, row 6
report
2362eutectic: (L)->Si3W5+bccL: W 0.671; Si3W5: W 0.625; bcc: W 0.97model[1] Vahlas 1989Table 8, p. 15, row 29
report
2358eutectic: (L)->Si3W5+bccL: W 0.68; Si3W5: W 0.625; bcc: W 0.96experimental[1] Vahlas 1989
cites ref. 51
Table 8, p. 15, row 33
report
2358eutectic: L->Bcc+W5Si3W5Si3: W 0.625experimental[3] Li 2013
cites Kocherzhinskii 1973
Table 2, p. 3, row 8
report
2358L <-> (W) + W5Si3L: Si 0.32; (W): Si 0.05; W5Si3: Si 0.375experimental[2] Guo 2009
cites Yu 1973
Table 5, p. 5, row 3
report
2343eutectic: (L)->Si2W+Si3W5L: W 0.43; Si2W: W 0.333333; Si3W5: W 0.625experimental[1] Vahlas 1989
cites ref. 47
Table 8, p. 15, row 18
report
2333eutectic: (L)->Si2W+Si3W5L: W 0.41; Si2W: W 0.333333; Si3W5: W 0.625experimental[1] Vahlas 1989
cites ref. 18
Table 8, p. 15, row 19
report
2293congruent melting: L <-> WSi2WSi2: Si 0.667experimental[2] Guo 2009
cites Yu 1973
Table 5, p. 5, row 12
report
2284L <-> W5Si3 + WSi2L: Si 0.532; W5Si3: Si 0.375; WSi2: Si 0.667model[2] Guo 2009Table 5, p. 5, row 7
report
2283L <-> W5Si3 + WSi2L: Si 0.593; W5Si3: Si 0.4; WSi2: Si 0.667experimental[2] Guo 2009
cites Maksimov 1969
Table 5, p. 5, row 8
report
2283eutectic: (L)->Si2W+Si3W5L: W 0.405; Si2W: W 0.333333; Si3W5: W 0.625experimental[1] Vahlas 1989
cites ref. 53
Table 8, p. 15, row 22
report
2283eutectic: (L)->Si2W+Si3W5L: W 0.405; Si2W: W 0.333333; Si3W5: W 0.625experimental[1] Vahlas 1989
cites ref. 48
Table 8, p. 15, row 20
report
2283eutectic: L->W5Si3+WSi2W5Si3: W 0.625; WSi2: W 0.333333experimental[3] Li 2013
cites Maksimov 1969
Table 2, p. 3, row 4
report
2213eutectic: L->W5Si3+WSi2W5Si3: W 0.625; WSi2: W 0.333333experimental[3] Li 2013
cites Kocherzhinskii 1973
Table 2, p. 3, row 9
report
2213eutectic: (L)->Si2W+Si3W5L: W 0.475; Si2W: W 0.333333; Si3W5: W 0.625model[1] Vahlas 1989Table 8, p. 15, row 17
report
2213L <-> W5Si3 + WSi2L: Si 0.53; W5Si3: Si 0.375; WSi2: Si 0.667experimental[2] Guo 2009
cites Yu 1973
Table 5, p. 5, row 9
report
2213eutectic: (L)->Si2W+Si3W5L: W 0.47; Si2W: W 0.333333; Si3W5: W 0.625experimental[1] Vahlas 1989
cites ref. 51
Table 8, p. 15, row 21
report
1673eutectic: (L)->Si(dia)+Si2WL: W 0.008; Si(dia): W 0; Si2W: W 0.333333experimental[1] Vahlas 1989
cites ref. 18
Table 8, p. 15, row 7
report
1673eutectic: (L)->Si(dia)+Si2WL: W 0.026; Si(dia): W 0; Si2W: W 0.333333experimental[1] Vahlas 1989
cites ref. 51
Table 8, p. 15, row 9
report
1673L <-> Si + WSi2L: Si 0.974; Si: Si 1; WSi2: Si 0.667experimental[2] Guo 2009
cites Yu 1973
Table 5, p. 5, row 15
report
1673eutectic: L->WSi2+SiWSi2: W 0.333333; Si: W 0experimental[3] Li 2013
cites Kocherzhinskii 1973
Table 2, p. 3, row 10
report
1666L <-> Si + WSi2L: Si 0.956; Si: Si 1; WSi2: Si 0.667model[2] Guo 2009Table 5, p. 5, row 13
report
1663L <-> Si + WSi2L: Si 0.992; Si: Si 1; WSi2: Si 0.667experimental[2] Guo 2009
cites Maksimov 1969
Table 5, p. 5, row 14
report
1663eutectic: (L)->Si(dia)+Si2WL: W 0.017; Si(dia): W 0; Si2W: W 0.333333experimental[1] Vahlas 1989
cites ref. 49
Table 8, p. 15, row 8
report
1663eutectic: L->WSi2+SiWSi2: W 0.333333; Si: W 0experimental[3] Li 2013
cites Maksimov 1969
Table 2, p. 3, row 5
report
1663eutectic: (L)->Si(dia)+Si2WL: W 0.001; Si(dia): W 0; Si2W: W 0.333333experimental[1] Vahlas 1989
cites ref. 48
Table 8, p. 15, row 6
report
1661eutectic: (L)->Si(dia)+Si2WL: W 0.014; Si(dia): W 0; Si2W: W 0.333333experimental[1] Vahlas 1989
cites ref. 53
Table 8, p. 15, row 10
report
1661eutectic: (L)->Si(dia)+Si2WL: W 0.043; Si(dia): W 0; Si2W: W 0.333333model[1] Vahlas 1989Table 8, p. 15, row 5
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, Si–W system (11)
PhaseCompoundValueT (K)ClassMP DFT (kJ/mol-atom)OQMD DFT (kJ/mol-atom)SourceLocationQuote
W5Si3-145 kJ/mol (basis unstated)model[3] Li 2013
cites Vahlas 1989 doi
Table 3, p. 3, row 6
report
W5Si3-138 kJ/mol (basis unstated)298.15experimental[3] Li 2013
cites Kematick 1993 doi
Table 3, p. 3, row 4
report
W5Si3-136 kJ/mol (basis unstated)model[3] Li 2013Table 3, p. 3, row 7
report
W5Si3-135 kJ/mol (basis unstated)298.15experimental[3] Li 2013
cites Chart 1975 doi
Table 3, p. 3, row 3
report
W5Si3-133 kJ/mol (basis unstated) ± 25298.15experimental[3] Li 2013
cites Fujiwara 2005 doi
Table 3, p. 3, row 5
report
WSi2-93.7 kJ/mol (basis unstated)298.15experimental[3] Li 2013
cites Robinson 1955
Table 3, p. 3, row 2
report
WSi2-93 kJ/mol (basis unstated)model[3] Li 2013
cites Vahlas 1989 doi
Table 3, p. 3, row 6
report
WSi2-92.7 kJ/mol (basis unstated)298.15experimental[3] Li 2013
cites Chart 1975 doi
Table 3, p. 3, row 3
report
WSi2-82 kJ/mol (basis unstated) ± 6298.15experimental[3] Li 2013
cites Fujiwara 2005 doi
Table 3, p. 3, row 5
report
WSi2-81 kJ/mol (basis unstated)model[3] Li 2013Table 3, p. 3, row 7
report
WSi2-79.6 kJ/mol (basis unstated)298.15experimental[3] Li 2013
cites Kematick 1993 doi
Table 3, p. 3, row 4
report

Other properties

Phase transition (24)

Phase transition, Si–W system
PropertyValueT (K)Phases / compositionClassSourceLocationQuote
Phase transition1685 K1685Si(dia)->Si(L)
Si(dia): W 0
experimental[1] Vahlas 1989
cites ref. 1
Table 8, p. 15, row 3
report
Phase transition1687 K1687Si(dia)->Si(L)
Si(dia): W 0
model[1] Vahlas 1989Table 8, p. 15, row 1
report
Phase transition1687 K1687Si(dia)->Si(L)
Si(dia): W 0
experimental[1] Vahlas 1989
cites ref. 3
Table 8, p. 15, row 2
report
Phase transition1693 K1693Si(dia)->Si(L)
Si(dia): W 0
experimental[1] Vahlas 1989
cites ref. 51
Table 8, p. 15, row 4
report
Phase transition2275 K2275Si2W->L
Si2W: W 0.333
model[1] Vahlas 1989Table 8, p. 15, row 11
report
Phase transition2293 K2293Si2W
Si2W: W 0.333333; L: W 0.333333
experimental[3] Li 2013
cites Kocherzhinskii 1973
Table 2, p. 3, row 11
report
Phase transition2293 K2293Si2W->L
Si2W: W 0.333333
experimental[1] Vahlas 1989
cites ref. 51
Table 8, p. 15, row 15
report
Phase transition2368 K2368Si3W5
Si3W5: W 0.625; L: W 0.625
experimental[3] Li 2013
cites Kocherzhinskii 1973
Table 2, p. 3, row 12
report
Phase transition2368 K2368Si3W5->(L)
Si3W5: W 0.625
experimental[1] Vahlas 1989
cites ref. 51
Table 8, p. 15, row 27
report
Phase transition2381 K2381Si3W5->(L)
Si3W5: W 0.625
model[1] Vahlas 1989Table 8, p. 15, row 23
report
Phase transition2433 K2433Si2W
Si2W: W 0.333333; L: W 0.333333
experimental[3] Li 2013
cites Maksimov 1969
Table 2, p. 3, row 6
report
Phase transition2433 K2433Si2W->L
Si2W: W 0.333333
experimental[1] Vahlas 1989
cites ref. 49
Table 8, p. 15, row 14
report
Phase transition2433 K2433Si2W->L
Si2W: W 0.333333
experimental[1] Vahlas 1989
cites ref. 53
Table 8, p. 15, row 16
report
Phase transition2436 K2436Si2W->L
Si2W: W 0.333333
experimental[1] Vahlas 1989
cites ref. 48
Table 8, p. 15, row 13
report
Phase transition2438 K2438Si2W
Si2W: W 0.333333; L: W 0.333333
experimental[3] Li 2013
cites Kieffer 1952
Table 2, p. 3, row 1
report
Phase transition2438 K2438Si2W->L
Si2W: W 0.333
experimental[1] Vahlas 1989
cites ref. 18
Table 8, p. 15, row 12
report
Phase transition2583 K2583Si3W5->(L)
Si3W5: W 0.625
experimental[1] Vahlas 1989
cites ref. 18
Table 8, p. 15, row 26
report
Phase transition2593 K2593Si3W5
Si3W5: W 0.625; L: W 0.625
experimental[3] Li 2013
cites Kieffer 1952
Table 2, p. 3, row 2
report
Phase transition2593 K2593Si3W5
Si3W5: W 0.625; L: W 0.625
experimental[3] Li 2013
cites Maksimov 1969
Table 2, p. 3, row 7
report
Phase transition2593 K2593Si3W5->(L)
Si3W5: W 0.625
experimental[1] Vahlas 1989
cites ref. 47
Table 8, p. 15, row 24
report
Phase transition2641 K2641Si3W5->(L)
Si3W5: W 0.625
experimental[1] Vahlas 1989
cites ref. 48
Table 8, p. 15, row 25
report
Phase transition3680 K3680W(bcc)->(L)
W(bcc): W 1
experimental[1] Vahlas 1989
cites ref. 58
Table 8, p. 15, row 36
report
Phase transition3695 K3695W(bcc)->(L)
W(bcc): W 1
experimental[1] Vahlas 1989
cites ref. 10
Table 8, p. 15, row 35
report
Phase transition3695 K3695W(bcc)->(L)
W(bcc): W 1
model[1] Vahlas 1989Table 8, p. 15, row 34
report

Crystal structure (4)

Crystal structure, Si–W system
PropertyValueT (K)Phases / compositionClassSourceLocationQuote
Lattice a9.59 Å298.15W5Si3
alloy: Si 0.375, W 0.625
model[3] Li 2013
cites Daams 1991
Table 1, p. 2, row 8
report
Lattice a3.22 Å298.15WSi2
alloy: Si 0.666667, W 0.333333
model[3] Li 2013
cites Daams 1991
Table 1, p. 2, row 9
report
Lattice c4.92 Å298.15W5Si3
alloy: Si 0.375, W 0.625
model[3] Li 2013
cites Daams 1991
Table 1, p. 2, row 8
report
Lattice c7.83 Å298.15WSi2
alloy: Si 0.666667, W 0.333333
model[3] Li 2013
cites Daams 1991
Table 1, p. 2, row 9
report

Sources

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

  1. C. Vahlas, P.Y. Chevalier, E. Blanquet, A thermodynamic evaluation of four Si-M (M = Mo, Ta, Ti, W) binary systems, Calphad 13, 273-292 (1989). doi:10.1016/0364-5916(89)90007-2
  2. Zhongnan Guo, Wenxia Yuan, Yu Sun, Zhoufei Cai, Zhiyu Qiao, Thermodynamic Assessment of the Si-Ta and Si-W Systems, J. Phase Equilib. Diffus. 30, 564-570 (2009). doi:10.1007/s11669-009-9579-x
  3. Yan Li, Changrong Li, Zhenmin Du, Cuiping Guo, Thermodynamic optimization of the Nb–Si–W ternary system, Calphad 43, 112-123 (2013). doi:10.1016/j.calphad.2013.04.004