Si–U system

41 accepted literature values from 1 paper(s) (experimental 24, model 17); 3 calculated phase diagram(s). 6 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 (15) · papers (bibliography) · Markdown

Accepted values by evidence class
Evidence classValues
experimental24
model17
Accepted values by property group
Property groupValues
phase transition12
phase equilibrium5
formation24

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
SiU-04Che-LB.tdbP.-Y. Chevalier, E. Fischer, unpublished work, 2004.84486566b19cb138031b465e37b18ece92a359534170a723ad939f5cd5611038viewer · TDB · JSON
SiU-09Ber.tdbA. Berche, C. Rado, O. Rapaud, C. Gueneau, J. Rogez, J. Nucl. Mater., 389, 101-7(2009). doi:10.1016/j.jnucmat.2009.01.014145f0a0d4b59bca1fec508ce829d2528d98fa56c9e95f1acd3e3120618d30dbcviewer · TDB · JSON
SiU-98AEA.tdbAEA Harwell, unpublished, 1998.ad20359bfb8262bf9f5c0d6705cba31e8dd0654d2d91e44a987d898df1edfd79viewer · TDB · JSON
Calculated three-phase invariants (model, mole fraction of the second component)
TDB fileT (K)Phases at the invariant
SiU-04Che-LB.tdb1975.44LIQUID (x(U) 0.30846) + SI2U_CC (x(U) 0.34722) + SI5U3_C32 (x(U) 0.375)
SiU-04Che-LB.tdb1975.44LIQUID (x(U) 0.30836) + SI2U_CC (x(U) 0.34722) + SI5U3_C32 (x(U) 0.375)
SiU-04Che-LB.tdb1975.44LIQUID (x(U) 0.30869) + SI2U_CC (x(U) 0.34722) + SI5U3_C32 (x(U) 0.375)
SiU-04Che-LB.tdb1849.6SI5U3_C32 (x(U) 0.375) + SIU_B27 (x(U) 0.489) + LIQUID (x(U) 0.49287)
SiU-04Che-LB.tdb1849.6SI5U3_C32 (x(U) 0.375) + SIU_B27 (x(U) 0.489) + LIQUID (x(U) 0.49278)
SiU-04Che-LB.tdb1833.55SIU_B27 (x(U) 0.489) + LIQUID (x(U) 0.52189) + SI2U3_D5A (x(U) 0.6)
SiU-04Che-LB.tdb1833.55SIU_B27 (x(U) 0.489) + LIQUID (x(U) 0.52179) + SI2U3_D5A (x(U) 0.6)
SiU-04Che-LB.tdb1833.55SIU_B27 (x(U) 0.489) + LIQUID (x(U) 0.52192) + SI2U3_D5A (x(U) 0.6)
SiU-04Che-LB.tdb1777.15LIQUID (x(U) 0.22422) + SI3U_L12 (x(U) 0.25) + SI2U_CC (x(U) 0.34722)
SiU-04Che-LB.tdb1777.14LIQUID (x(U) 0.22393) + SI3U_L12 (x(U) 0.25) + SI2U_CC (x(U) 0.34722)
SiU-04Che-LB.tdb1777.14LIQUID (x(U) 0.22387) + SI3U_L12 (x(U) 0.25) + SI2U_CC (x(U) 0.34722)
SiU-04Che-LB.tdb1591.92DIAMOND_A4 (x(U) 0) + LIQUID (x(U) 0.12347) + SI3U_L12 (x(U) 0.25)
SiU-04Che-LB.tdb1591.92DIAMOND_A4 (x(U) 0) + LIQUID (x(U) 0.12326) + SI3U_L12 (x(U) 0.25)
SiU-04Che-LB.tdb1591.92DIAMOND_A4 (x(U) 0) + LIQUID (x(U) 0.12316) + SI3U_L12 (x(U) 0.25)
SiU-04Che-LB.tdb1260.64SI2U3_D5A (x(U) 0.6) + LIQUID (x(U) 0.88599) + BCC_A2 (x(U) 0.98727)
SiU-04Che-LB.tdb1260.64SI2U3_D5A (x(U) 0.6) + LIQUID (x(U) 0.88614) + BCC_A2 (x(U) 0.98727)
SiU-04Che-LB.tdb1194.1SI2U3_D5A (x(U) 0.6) + SIU3_L12 (x(U) 0.75) + BCC_A2 (x(U) 0.99048)
SiU-04Che-LB.tdb1194.1SI2U3_D5A (x(U) 0.6) + SIU3_L12 (x(U) 0.75) + BCC_A2 (x(U) 0.99047)
SiU-04Che-LB.tdb1057.52SIU3_L12 (x(U) 0.75) + TETRAGONAL_U (x(U) 0.99178) + BCC_A2 (x(U) 0.99576)
SiU-04Che-LB.tdb1037.98SI2U3_D5A (x(U) 0.6) + SIU3_D0C (x(U) 0.75) + SIU3_L12 (x(U) 0.75)
SiU-04Che-LB.tdb1037.98SIU3_D0C (x(U) 0.75) + SIU3_L12 (x(U) 0.75) + TETRAGONAL_U (x(U) 0.99237)
SiU-04Che-LB.tdb937.94SIU3_D0C (x(U) 0.75) + TETRAGONAL_U (x(U) 0.99533) + ORTHORHOMBIC_A20 (x(U) 0.99678)
SiU-09Ber.tdb1995.22LIQUID (x(U) 0.3155) + SI2U_CC (x(U) 0.34722) + SI5U3_C32 (x(U) 0.375)
SiU-09Ber.tdb1995.21LIQUID (x(U) 0.31518) + SI2U_CC (x(U) 0.34722) + SI5U3_C32 (x(U) 0.375)
SiU-09Ber.tdb1995.21LIQUID (x(U) 0.315) + SI2U_CC (x(U) 0.34722) + SI5U3_C32 (x(U) 0.375)
SiU-09Ber.tdb1851.58SI5U3_C32 (x(U) 0.375) + SIU_B27 (x(U) 0.49635) + LIQUID (x(U) 0.49719)
SiU-09Ber.tdb1851.58SI5U3_C32 (x(U) 0.375) + SIU_B27 (x(U) 0.49635) + LIQUID (x(U) 0.49696)
SiU-09Ber.tdb1837.56SIU_B27 (x(U) 0.49635) + LIQUID (x(U) 0.52905) + SI2U3_D5A (x(U) 0.6)
SiU-09Ber.tdb1837.56SIU_B27 (x(U) 0.49635) + LIQUID (x(U) 0.529) + SI2U3_D5A (x(U) 0.6)
SiU-09Ber.tdb1837.56SIU_B27 (x(U) 0.49635) + LIQUID (x(U) 0.52933) + SI2U3_D5A (x(U) 0.6)
SiU-09Ber.tdb1795.75LIQUID (x(U) 0.20713) + SI3U_L12 (x(U) 0.25) + SI2U_CC (x(U) 0.34722)
SiU-09Ber.tdb1795.75LIQUID (x(U) 0.2074) + SI3U_L12 (x(U) 0.25) + SI2U_CC (x(U) 0.34722)
SiU-09Ber.tdb1795.75LIQUID (x(U) 0.20708) + SI3U_L12 (x(U) 0.25) + SI2U_CC (x(U) 0.34722)
SiU-09Ber.tdb1596.94DIAMOND_A4 (x(U) 0) + LIQUID (x(U) 0.10631) + SI3U_L12 (x(U) 0.25)
SiU-09Ber.tdb1596.94DIAMOND_A4 (x(U) 0) + LIQUID (x(U) 0.10619) + SI3U_L12 (x(U) 0.25)
SiU-09Ber.tdb1596.94DIAMOND_A4 (x(U) 0) + LIQUID (x(U) 0.10613) + SI3U_L12 (x(U) 0.25)
SiU-09Ber.tdb1249.45SI2U3_D5A (x(U) 0.6) + LIQUID (x(U) 0.87171) + BCC_A2 (x(U) 0.97214)
SiU-09Ber.tdb1249.45SI2U3_D5A (x(U) 0.6) + LIQUID (x(U) 0.87184) + BCC_A2 (x(U) 0.97217)
SiU-09Ber.tdb1192.9SI2U3_D5A (x(U) 0.6) + SIU3 (x(U) 0.75) + BCC_A2 (x(U) 0.97625)
SiU-09Ber.tdb1192.9SI2U3_D5A (x(U) 0.6) + SIU3 (x(U) 0.75) + BCC_A2 (x(U) 0.97627)
SiU-09Ber.tdb1052.43SIU3 (x(U) 0.75) + TETRAGONAL_U (x(U) 0.98734) + BCC_A2 (x(U) 0.98898)
SiU-09Ber.tdb920.83SIU3 (x(U) 0.75) + TETRAGONAL_U (x(U) 0.99225) + ORTHORHOMBIC_A20 (x(U) 1)
SiU-09Ber.tdb920.82SIU3 (x(U) 0.75) + TETRAGONAL_U (x(U) 0.99229) + ORTHORHOMBIC_A20 (x(U) 1)
SiU-98AEA.tdb1910.55LIQUID (x(U) 0.26656) + SI2U_CC (x(U) 0.33333) + SI5U3_C32 (x(U) 0.375)
SiU-98AEA.tdb1910.55LIQUID (x(U) 0.26649) + SI2U_CC (x(U) 0.33333) + SI5U3_C32 (x(U) 0.375)
SiU-98AEA.tdb1910.55LIQUID (x(U) 0.26666) + SI2U_CC (x(U) 0.33333) + SI5U3_C32 (x(U) 0.375)
SiU-98AEA.tdb1871.05SI5U3_C32 (x(U) 0.375) + SIU_B27 (x(U) 0.5) + LIQUID (x(U) 0.51018)
SiU-98AEA.tdb1871.05SI5U3_C32 (x(U) 0.375) + SIU_B27 (x(U) 0.5) + LIQUID (x(U) 0.51008)
SiU-98AEA.tdb1870.46SIU_B27 (x(U) 0.5) + LIQUID (x(U) 0.51321) + SI2U3_D5A (x(U) 0.6)
SiU-98AEA.tdb1870.46SIU_B27 (x(U) 0.5) + LIQUID (x(U) 0.51331) + SI2U3_D5A (x(U) 0.6)
SiU-98AEA.tdb1778.47LIQUID (x(U) 0.19125) + SI3U_L12 (x(U) 0.25) + SI2U_CC (x(U) 0.33333)
SiU-98AEA.tdb1778.47LIQUID (x(U) 0.1913) + SI3U_L12 (x(U) 0.25) + SI2U_CC (x(U) 0.33333)
SiU-98AEA.tdb1778.47LIQUID (x(U) 0.19122) + SI3U_L12 (x(U) 0.25) + SI2U_CC (x(U) 0.33333)
SiU-98AEA.tdb1604.82DIAMOND_A4 (x(U) 0) + LIQUID (x(U) 0.09784) + SI3U_L12 (x(U) 0.25)
SiU-98AEA.tdb1604.82DIAMOND_A4 (x(U) 0) + LIQUID (x(U) 0.09776) + SI3U_L12 (x(U) 0.25)
SiU-98AEA.tdb1604.82DIAMOND_A4 (x(U) 0) + LIQUID (x(U) 0.09774) + SI3U_L12 (x(U) 0.25)
SiU-98AEA.tdb1277SI2U3_D5A (x(U) 0.6) + LIQUID (x(U) 0.90816) + BCC_A2 (x(U) 1)
SiU-98AEA.tdb1205.16SI2U3_D5A (x(U) 0.6) + SIU3 (x(U) 0.75) + BCC_A2 (x(U) 1)
SiU-98AEA.tdb1048.99SIU3 (x(U) 0.75) + BCC_A2 (x(U) 1) + TETRAGONAL_U (x(U) 1)
SiU-98AEA.tdb942.02SIU3 (x(U) 0.75) + ORTHORHOMBIC_A20 (x(U) 1) + TETRAGONAL_U (x(U) 1)

Convex hulls: Materials Project DFT hull · OQMD DFT hull · CALPHAD hull SiU-04Che-LB · CALPHAD hull SiU-98AEA

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–U system (24)
PhaseCompoundValueT (K)ClassMP DFT (kJ/mol-atom)OQMD DFT (kJ/mol-atom)SourceLocationQuote
U3SiSiU3-26.02 kJ/mol-atom ± 4.8298.15experimental-21.811 (mp-aaaaabku)-23.444 (oqmd-1995)[1] Berche 2009
cites OHare 1975
Table 2, p. 2, row 22
report
U3SiSiU3-24.93 kJ/mol-atom298.15model-21.811 (mp-aaaaabku)-23.444 (oqmd-1995)[1] Berche 2009Table 2, p. 2, row 24
report
U3SiSiU3-22.99 kJ/mol-atom298.15model-21.811 (mp-aaaaabku)-23.444 (oqmd-1995)[1] Berche 2009
cites Rand 2009
Table 2, p. 2, row 23
report
U3Si2Si2U3-35.95 kJ/mol-atom ± 3.34298.15experimental-10.03 (mp-aaaabfpa)-14.346 (oqmd-6055)[1] Berche 2009
cites Alcock 1962
Table 2, p. 2, row 19
report
U3Si2Si2U3-34.32 kJ/mol-atom298.15model-10.03 (mp-aaaabfpa)-14.346 (oqmd-6055)[1] Berche 2009Table 2, p. 2, row 21
report
U3Si2Si2U3-34.11 kJ/mol-atom298.15model-10.03 (mp-aaaabfpa)-14.346 (oqmd-6055)[1] Berche 2009
cites Rand 2009
Table 2, p. 2, row 20
report
U3Si2Si2U3-33.86 kJ/mol-atom ± 0.42298.15experimental-10.03 (mp-aaaabfpa)-14.346 (oqmd-6055)[1] Berche 2009
cites Gross 1962
Table 2, p. 2, row 18
report
U3Si5-44.26 kJ/mol-atom298.15model[1] Berche 2009
cites Rand 2009
Table 2, p. 2, row 11
report
U3Si5-42.9 kJ/mol-atom298.15model[1] Berche 2009Table 2, p. 2, row 12
report
USiSiU-43.47 kJ/mol-atom ± 1.67298.15experimental-16.795 (mp-aaaabdeh)-19.948 (oqmd-6064)[1] Berche 2009
cites Gross 1962
Table 2, p. 2, row 14
report
USiSiU-42.22 kJ/mol-atom298.15model-16.795 (mp-aaaabdeh)-19.948 (oqmd-6064)[1] Berche 2009
cites Rand 2009
Table 2, p. 2, row 16
report
USiSiU-41.8 kJ/mol-atom ± 4.18298.15experimental-16.795 (mp-aaaabdeh)-19.948 (oqmd-6064)[1] Berche 2009
cites Alcock 1962
Table 2, p. 2, row 15
report
USiSiU-41.18 kJ/mol-atom298.15model-16.795 (mp-aaaabdeh)-19.948 (oqmd-6064)[1] Berche 2009Table 2, p. 2, row 17
report
USiSiU-40.13 kJ/mol-atom ± 0.84298.15experimental-16.795 (mp-aaaabdeh)-19.948 (oqmd-6064)[1] Berche 2009
cites Gross 1962
Table 2, p. 2, row 13
report
USi2Si2U-43.89 kJ/mol-atom ± 4.18298.15experimental-27.301 (mp-aaaaabls)-31.404 (oqmd-670765)[1] Berche 2009
cites Alcock 1962
Table 2, p. 2, row 8
report
USi2Si2U-43.47 kJ/mol-atom ± 0.42298.15experimental-27.301 (mp-aaaaabls)-31.404 (oqmd-670765)[1] Berche 2009
cites Gross 1962
Table 2, p. 2, row 6
report
USi2Si2U-43.33 kJ/mol-atom298.15model-27.301 (mp-aaaaabls)-31.404 (oqmd-670765)[1] Berche 2009Table 2, p. 2, row 10
report
USi2Si2U-43.19 kJ/mol-atom298.15model-27.301 (mp-aaaaabls)-31.404 (oqmd-670765)[1] Berche 2009
cites Rand 2009
Table 2, p. 2, row 9
report
USi2Si2U-42.64 kJ/mol-atom ± 1.25298.15experimental-27.301 (mp-aaaaabls)-31.404 (oqmd-670765)[1] Berche 2009
cites Gross 1962
Table 2, p. 2, row 7
report
USi3Si3U-35.53 kJ/mol-atom ± 4.18298.15experimental-31.163 (mp-aaaaaeds)-36.154 (oqmd-18109)[1] Berche 2009
cites Alcock 1962
Table 2, p. 2, row 3
report
USi3Si3U-33.02 kJ/mol-atom ± 0.13298.15experimental-31.163 (mp-aaaaaeds)-36.154 (oqmd-18109)[1] Berche 2009
cites Gross 1962
Table 2, p. 2, row 1
report
USi3Si3U-32.9 kJ/mol-atom298.15model-31.163 (mp-aaaaaeds)-36.154 (oqmd-18109)[1] Berche 2009Table 2, p. 2, row 5
report
USi3Si3U-32.6 kJ/mol-atom298.15model-31.163 (mp-aaaaaeds)-36.154 (oqmd-18109)[1] Berche 2009
cites Rand 2009
Table 2, p. 2, row 4
report
USi3Si3U-32.19 kJ/mol-atom ± 0.84298.15experimental-31.163 (mp-aaaaaeds)-36.154 (oqmd-18109)[1] Berche 2009
cites Gross 1962
Table 2, p. 2, row 2
report

Other properties

Phase transition (12)

Phase transition, Si–U system
PropertyValueT (K)Phases / compositionClassSourceLocationQuote
Phase transition1250 K1250eutectic: 4 at.% Si
alloy: Si 0.0397, U 0.9603
model[1] Berche 2009Table 1, p. 2, row 5
report
Phase transition1250 K1250eutectic: 9 at.% Si
alloy: Si 0.0869, U 0.9131
model[1] Berche 2009Table 1, p. 2, row 11
report
Phase transition1258 K1258eutectic: 4 at.% Si
alloy: Si 0.0397, U 0.9603
experimental[1] Berche 2009
cites Katz 1951
Table 1, p. 2, row 3
report
Phase transition1258 K1258eutectic: 9 at.% Si
alloy: Si 0.0869, U 0.9131
experimental[1] Berche 2009
cites Katz 1951
Table 1, p. 2, row 9
report
Phase transition1261 K1261eutectic: 9 at.% Si
alloy: Si 0.0869, U 0.9131
experimental[1] Berche 2009Table 1, p. 2, row 10
report
Phase transition1267 K1267eutectic: 4 at.% Si
alloy: Si 0.0397, U 0.9603
experimental[1] Berche 2009Table 1, p. 2, row 4
report
Phase transition1405 K1405congruent transformation: 0 at.% Si
alloy: U 0
experimental[1] Berche 2009Table 1, p. 2, row 2
report
Phase transition1408 K1408congruent transformation: 0 at.% Si
alloy: U 0
experimental[1] Berche 2009Table 1, p. 2, row 1
report
Phase transition1783 K1783peritectic: 75 at.% Si
alloy: Si 0.7468, U 0.2532
experimental[1] Berche 2009
cites Katz 1951
Table 1, p. 2, row 17
report
Phase transition1813 K1813eutectic: 46 at.% Si
alloy: Si 0.4632, U 0.5368
experimental[1] Berche 2009
cites Vaugoyeau 1971 doi
Table 1, p. 2, row 12
report
Phase transition1820 K1820eutectic: 46 at.% Si
alloy: Si 0.4632, U 0.5368
experimental[1] Berche 2009Table 1, p. 2, row 13
report
Phase transition1840 K1840eutectic: 46 at.% Si
alloy: Si 0.4632, U 0.5368
model[1] Berche 2009Table 1, p. 2, row 14
report

Phase equilibrium (5)

Phase equilibrium, Si–U system
PropertyValueT (K)Phases / compositionClassSourceLocationQuote
Phase composition1340other: 4 at.% Si
liquid: Si 0.0397, U 0.9603
experimental[1] Berche 2009Table 1, p. 2, row 7
report
Phase composition1360other: 4 at.% Si
liquid: Si 0.0397, U 0.9603
model[1] Berche 2009Table 1, p. 2, row 8
report
Phase composition1363other: 4 at.% Si
liquid: Si 0.0397, U 0.9603
experimental[1] Berche 2009
cites Massalski 1990
Table 1, p. 2, row 6
report
Phase composition1860other: 46 at.% Si
liquid: Si 0.4632, U 0.5368
model[1] Berche 2009Table 1, p. 2, row 16
report
Phase composition1867other: 46 at.% Si
liquid: Si 0.4632, U 0.5368
experimental[1] Berche 2009Table 1, p. 2, row 15
report

Sources

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

  1. A. Berche, C. Rado, O. Rapaud, C. Guéneau, J. Rogez, Thermodynamic study of the U–Si system, Journal of Nuclear Materials 389, 101-107 (2009). doi:10.1016/j.jnucmat.2009.01.014