{
  "spore": "profile",
  "id": "aluminium-silicon-ce7",
  "spore_version": "0.2",
  "family": "aluminium-alloys",
  "name": "Osprey CE7 silicon-aluminium alloy",
  "abbreviation": "CE7",
  "role": "controlled-expansion packaging alloy (Si-30%Al, Osprey CE7F)",
  "category": "metals",
  "type": "aluminium",
  "summary": "CE7 is an Osprey silicon-aluminium alloy (Si-30%Al, about 70 % Si and 30 % Al by weight) with interwoven silicon and aluminium phases and a grain size of about 10 µm (arXiv 2018). Its room-temperature expansion is 7.2 ppm/°C on the maker's current listing, and 7.5 ppm/°C from 25 °C to 500 °C in a 2003 article, close to gallium arsenide and alumina. The 2018 arXiv paper measured superconductivity at 1.190 K and poor heat conduction at 300 mK. No flight or spacecraft record was found in the sources read.",
  "best_for": "Machined housings, carriers and interface plates for silicon and gallium arsenide microwave parts, and for cryogenic millimetre-wave detectors, where the expansion must stay close to that of the part",
  "weakest_at": "Brittleness (yield and ultimate tensile strength are nearly the same) and poor thermal conduction at cryogenic temperatures unless the parts are gold plated",
  "identity": {
    "formula": "Si-Al alloy, about 70 % Si and 30 % Al by weight (printed as Si-30%Al)",
    "cas": "",
    "designations": [
      {
        "system": "Trade name",
        "code": "CE7F",
        "note": "Osprey CE7F, controlled expansion aluminium-silicon alloy",
        "source": "ospreyatomiqs-materials",
        "where": "Controlled expansion alloys list, entry Osprey CE7F"
      },
      {
        "system": "Trade name",
        "code": "CE7",
        "note": "older name, printed without the F suffix",
        "source": "mwj-osprey-2003",
        "where": "Table 1 Key Properties, column header CE7"
      }
    ],
    "source": "ospreyatomiqs-materials",
    "where": "Controlled expansion alloys list, entry Osprey CE7F, printed as Si-30%Al"
  },
  "tags": {
    "environments": [],
    "stresses": [
      "extreme-cold"
    ],
    "applications": [
      "electronics-and-chips",
      "optics-and-cameras",
      "thermal-control"
    ]
  },
  "properties": [
    {
      "benchmark": "density",
      "label": "Density, CE7 (arXiv Table 1)",
      "value": 2.43,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "temperature": "not stated in table",
        "form": "not stated"
      },
      "method": "Value printed in Table 1 of the 2018 arXiv paper, column CE7. The paper credits its mechanical values to Sandvik Osprey measurements at room temperature.",
      "status": "ground",
      "source": "arxiv-ali-2018",
      "where": "Table 1, row Density (g/cm3), column CE7",
      "source_detail": {
        "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
        "id": "arXiv:1807.03398",
        "url": "https://arxiv.org/pdf/1807.03398",
        "year": 2018,
        "kind": "paper",
        "license": "arXiv preprint (cited, not reproduced)"
      }
    },
    {
      "benchmark": "density",
      "label": "Density, CE7F (Osprey current listing)",
      "value": 2.43,
      "bound": "exact",
      "unit": "g/cc",
      "scope": "material",
      "conditions": {
        "grade": "Osprey CE7F, Si-30%Al",
        "temperature": "not stated"
      },
      "method": "Value printed on the maker's current materials listing",
      "status": "ground",
      "source": "ospreyatomiqs-materials",
      "where": "Controlled expansion alloys list, entry Osprey CE7F (printed as a density of 2.43 g/cc)",
      "source_detail": {
        "title": "Osprey Atomiqs materials list, controlled expansion alloys (entry Osprey CE7F)",
        "url": "https://www.ospreyatomiqs.com/materials",
        "kind": "datasheet",
        "license": "Manufacturer materials listing (cited, not reproduced)"
      }
    },
    {
      "benchmark": "cte",
      "label": "Coefficient of thermal expansion at room temperature (Osprey current listing)",
      "value": 7.2,
      "bound": "exact",
      "unit": "ppm/°C",
      "scope": "material",
      "conditions": {
        "grade": "Osprey CE7F, Si-30%Al",
        "temperature": "room temperature (as printed)"
      },
      "method": "Value printed on the maker's current materials listing",
      "status": "ground",
      "source": "ospreyatomiqs-materials",
      "where": "Controlled expansion alloys list, entry Osprey CE7F (printed as a room-temperature expansion of 7.2 ppm/°C)",
      "source_detail": {
        "title": "Osprey Atomiqs materials list, controlled expansion alloys (entry Osprey CE7F)",
        "url": "https://www.ospreyatomiqs.com/materials",
        "kind": "datasheet",
        "license": "Manufacturer materials listing (cited, not reproduced)"
      }
    },
    {
      "benchmark": "cte",
      "label": "Coefficient of thermal expansion, 25 °C to 500 °C (Microwave Journal 2003)",
      "value": 7.5,
      "bound": "exact",
      "unit": "ppm/°C",
      "scope": "material",
      "conditions": {
        "temperature_range": "25 °C to 500 °C",
        "grade": "CE7, Si-30% Al"
      },
      "method": "Value printed in the property table of a 2003 Osprey Metals article in Microwave Journal",
      "status": "ground",
      "source": "mwj-osprey-2003",
      "where": "Table 1 Key Properties, row Coefficient of thermal expansion 25°C - 500°C, column CE7",
      "source_detail": {
        "title": "Osprey Metals, Controlled Expansion Alloys for High Reliability Packaging Solutions (Microwave Journal, article dated January 1, 2003)",
        "url": "https://www.microwavejournal.com/articles/3571-controlled-expansion-alloys-for-high-reliability-packaging-solutions",
        "year": 2003,
        "kind": "web",
        "license": "Trade journal article (cited, not reproduced)"
      }
    },
    {
      "benchmark": "cte",
      "label": "Coefficient of thermal expansion, 25 °C to 500 °C (LookPolymers record)",
      "value": 7.7,
      "bound": "exact",
      "unit": "µm/m-°C",
      "scope": "material",
      "conditions": {
        "temperature_range": "25.0 - 500 °C",
        "grade": "Si-30%Al"
      },
      "method": "Value printed in the Thermal Properties table of a MatWeb-format record, information provided by Osprey Metals",
      "status": "ground",
      "source": "lookpolymers-ce7",
      "where": "Thermal Properties table, row CTE linear, @Temperature 25.0 - 500 °C",
      "source_detail": {
        "title": "LookPolymers record: Osprey Metals CE7 Al-Si Controlled Expansion Alloy (MatWeb-format, information provided by Osprey Metals)",
        "url": "https://www.lookpolymers.com/polymer_Osprey-Metals-CE7-Al-Si-Controlled-Expansion-Alloy.php",
        "kind": "datasheet",
        "license": "Supplier record (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Young's modulus, CE7 (arXiv Table 1)",
      "value": 129.2,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "temperature": "not stated (mechanical values measured at room temperature by Sandvik Osprey, per the paper)"
      },
      "method": "Value printed in Table 1 of the 2018 arXiv paper",
      "status": "ground",
      "source": "arxiv-ali-2018",
      "where": "Table 1, row Young's modulus (GPa), column CE7",
      "source_detail": {
        "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
        "id": "arXiv:1807.03398",
        "url": "https://arxiv.org/pdf/1807.03398",
        "year": 2018,
        "kind": "paper",
        "license": "arXiv preprint (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Modulus of elasticity (Microwave Journal 2003)",
      "value": 120,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "grade": "CE7, Si-30% Al",
        "temperature": "not stated"
      },
      "method": "Value printed in the property table of a 2003 Osprey Metals article",
      "status": "ground",
      "source": "mwj-osprey-2003",
      "where": "Table 1 Key Properties, row Youngs Modulus (GPa), column CE7",
      "source_detail": {
        "title": "Osprey Metals, Controlled Expansion Alloys for High Reliability Packaging Solutions (Microwave Journal, article dated January 1, 2003)",
        "url": "https://www.microwavejournal.com/articles/3571-controlled-expansion-alloys-for-high-reliability-packaging-solutions",
        "year": 2003,
        "kind": "web",
        "license": "Trade journal article (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Modulus of elasticity (LookPolymers record)",
      "value": 125,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "grade": "Si-30%Al",
        "temperature": "not stated"
      },
      "method": "Value printed in the Mechanical Properties table of a MatWeb-format record, information provided by Osprey Metals",
      "status": "ground",
      "source": "lookpolymers-ce7",
      "where": "Mechanical Properties table, row Modulus of Elasticity, metric 125 GPa",
      "source_detail": {
        "title": "LookPolymers record: Osprey Metals CE7 Al-Si Controlled Expansion Alloy (MatWeb-format, information provided by Osprey Metals)",
        "url": "https://www.lookpolymers.com/polymer_Osprey-Metals-CE7-Al-Si-Controlled-Expansion-Alloy.php",
        "kind": "datasheet",
        "license": "Supplier record (cited, not reproduced)"
      }
    },
    {
      "benchmark": "shear_modulus",
      "label": "Rigidity (shear) modulus, CE7 (arXiv Table 1)",
      "value": 51.6,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "temperature": "not stated in table"
      },
      "method": "Value printed in Table 1 of the 2018 arXiv paper",
      "status": "ground",
      "source": "arxiv-ali-2018",
      "where": "Table 1, row Rigidity modulus (GPa), column CE7",
      "source_detail": {
        "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
        "id": "arXiv:1807.03398",
        "url": "https://arxiv.org/pdf/1807.03398",
        "year": 2018,
        "kind": "paper",
        "license": "arXiv preprint (cited, not reproduced)"
      }
    },
    {
      "benchmark": "shear_modulus",
      "label": "Shear modulus (LookPolymers record)",
      "value": 50,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "grade": "Si-30%Al",
        "temperature": "not stated"
      },
      "method": "Printed in the record's Shear Modulus row, which is marked Calculated in the source",
      "status": "calculated",
      "source": "lookpolymers-ce7",
      "where": "Mechanical Properties table, row Shear Modulus, metric 50.0 GPa (marked Calculated)",
      "source_detail": {
        "title": "LookPolymers record: Osprey Metals CE7 Al-Si Controlled Expansion Alloy (MatWeb-format, information provided by Osprey Metals)",
        "url": "https://www.lookpolymers.com/polymer_Osprey-Metals-CE7-Al-Si-Controlled-Expansion-Alloy.php",
        "kind": "datasheet",
        "license": "Supplier record (cited, not reproduced)"
      }
    },
    {
      "benchmark": "poissons_ratio",
      "label": "Poisson's ratio, CE7 (arXiv Table 1)",
      "value": 0.26,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "temperature": "not stated in table"
      },
      "method": "Value printed in Table 1 of the 2018 arXiv paper",
      "status": "ground",
      "source": "arxiv-ali-2018",
      "where": "Table 1, row Poisson's ratio, column CE7",
      "source_detail": {
        "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
        "id": "arXiv:1807.03398",
        "url": "https://arxiv.org/pdf/1807.03398",
        "year": 2018,
        "kind": "paper",
        "license": "arXiv preprint (cited, not reproduced)"
      }
    },
    {
      "benchmark": "poissons_ratio",
      "label": "Poisson's ratio (LookPolymers record)",
      "value": 0.25,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "grade": "Si-30%Al",
        "temperature": "not stated"
      },
      "method": "Value printed in the Mechanical Properties table of a MatWeb-format record",
      "status": "ground",
      "source": "lookpolymers-ce7",
      "where": "Mechanical Properties table, row Poissons Ratio, value 0.25",
      "source_detail": {
        "title": "LookPolymers record: Osprey Metals CE7 Al-Si Controlled Expansion Alloy (MatWeb-format, information provided by Osprey Metals)",
        "url": "https://www.lookpolymers.com/polymer_Osprey-Metals-CE7-Al-Si-Controlled-Expansion-Alloy.php",
        "kind": "datasheet",
        "license": "Supplier record (cited, not reproduced)"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Yield strength, CE7 (arXiv Table 1)",
      "value": 110,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "test": "room temperature, mechanical measurement by Sandvik Osprey (per the paper)",
        "form": "not stated"
      },
      "method": "Value printed in Table 1 of the 2018 arXiv paper. The table lists yield above the ultimate strength of about 100 MPa, and the paper describes the two as similar.",
      "status": "ground",
      "source": "arxiv-ali-2018",
      "where": "Table 1, row Yield strength (MPa), column CE7",
      "source_detail": {
        "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
        "id": "arXiv:1807.03398",
        "url": "https://arxiv.org/pdf/1807.03398",
        "year": 2018,
        "kind": "paper",
        "license": "arXiv preprint (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Ultimate tensile strength, CE7 (arXiv Table 1)",
      "value": 100,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "printed": "approximately 100 (printed as ∼100)",
        "test": "room temperature, mechanical measurement by Sandvik Osprey (per the paper)"
      },
      "method": "Value printed as approximately 100 in Table 1 of the 2018 arXiv paper",
      "status": "ground",
      "source": "arxiv-ali-2018",
      "where": "Table 1, row Ultimate tensile strength (MPa), column CE7 (printed as ∼100)",
      "source_detail": {
        "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
        "id": "arXiv:1807.03398",
        "url": "https://arxiv.org/pdf/1807.03398",
        "year": 2018,
        "kind": "paper",
        "license": "arXiv preprint (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength, ultimate (LookPolymers record)",
      "value": 100,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "grade": "Si-30%Al",
        "temperature": "not stated"
      },
      "method": "Value printed in the Mechanical Properties table of a MatWeb-format record",
      "status": "ground",
      "source": "lookpolymers-ce7",
      "where": "Mechanical Properties table, row Tensile Strength Ultimate, metric 100 MPa",
      "source_detail": {
        "title": "LookPolymers record: Osprey Metals CE7 Al-Si Controlled Expansion Alloy (MatWeb-format, information provided by Osprey Metals)",
        "url": "https://www.lookpolymers.com/polymer_Osprey-Metals-CE7-Al-Si-Controlled-Expansion-Alloy.php",
        "kind": "datasheet",
        "license": "Supplier record (cited, not reproduced)"
      }
    },
    {
      "benchmark": "flexural_strength",
      "label": "Bend strength, three point (Microwave Journal 2003)",
      "value": 150,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "test": "three point bend",
        "grade": "CE7, Si-30% Al"
      },
      "method": "Value printed in the property table of a 2003 Osprey Metals article",
      "status": "ground",
      "source": "mwj-osprey-2003",
      "where": "Table 1 Key Properties, row Bend Strength (three point) (MPa), column CE7",
      "source_detail": {
        "title": "Osprey Metals, Controlled Expansion Alloys for High Reliability Packaging Solutions (Microwave Journal, article dated January 1, 2003)",
        "url": "https://www.microwavejournal.com/articles/3571-controlled-expansion-alloys-for-high-reliability-packaging-solutions",
        "year": 2003,
        "kind": "web",
        "license": "Trade journal article (cited, not reproduced)"
      }
    },
    {
      "benchmark": "flexural_strength",
      "label": "Flexural strength (LookPolymers record)",
      "value": 143,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "grade": "Si-30%Al",
        "test": "not stated"
      },
      "method": "Value printed in the Mechanical Properties table of a MatWeb-format record",
      "status": "ground",
      "source": "lookpolymers-ce7",
      "where": "Mechanical Properties table, row Flexural Strength, metric 143 MPa",
      "source_detail": {
        "title": "LookPolymers record: Osprey Metals CE7 Al-Si Controlled Expansion Alloy (MatWeb-format, information provided by Osprey Metals)",
        "url": "https://www.lookpolymers.com/polymer_Osprey-Metals-CE7-Al-Si-Controlled-Expansion-Alloy.php",
        "kind": "datasheet",
        "license": "Supplier record (cited, not reproduced)"
      }
    },
    {
      "benchmark": "superconducting_critical_temperature",
      "label": "Superconducting critical temperature, CE7 (arXiv)",
      "value": 1.19,
      "bound": "exact",
      "unit": "K",
      "scope": "material",
      "conditions": {
        "definition": "point where the resistivity is half of the normal value",
        "apparatus": "four-lead resistance in an ADR cryostat"
      },
      "method": "Four-lead resistance measurement, 25 sweeps averaged, in the 2018 arXiv paper",
      "status": "ground",
      "uncertainty": "± .005 K (printed)",
      "source": "arxiv-ali-2018",
      "where": "Section 2.1 Superconductivity, text: Tc = 1.190 ± .005 K",
      "source_detail": {
        "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
        "id": "arXiv:1807.03398",
        "url": "https://arxiv.org/pdf/1807.03398",
        "year": 2018,
        "kind": "paper",
        "license": "arXiv preprint (cited, not reproduced)"
      }
    },
    {
      "benchmark": "electrical_resistivity",
      "label": "Electrical resistivity above about 1.2 K (arXiv)",
      "value": 0.5,
      "bound": "exact",
      "unit": "µΩ·m",
      "scope": "material",
      "conditions": {
        "temperature": "above about 1.2 K (text); 1.5 K (Table 1)",
        "uncertainty_in_source": "± .03 (text)"
      },
      "method": "Four-lead resistance measurement in the 2018 arXiv paper",
      "status": "ground",
      "source": "arxiv-ali-2018",
      "where": "Section 2.1 text (0.50 ± .03 µΩ·m) and Table 1, row Resistivity 1.5 K (µΩ·m)",
      "source_detail": {
        "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
        "id": "arXiv:1807.03398",
        "url": "https://arxiv.org/pdf/1807.03398",
        "year": 2018,
        "kind": "paper",
        "license": "arXiv preprint (cited, not reproduced)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity of bare CE7 at 300 mK (arXiv)",
      "value": 0.005,
      "bound": "exact",
      "unit": "W/m·K",
      "scope": "material",
      "conditions": {
        "temperature": "300 mK",
        "finish": "bare, not plated",
        "sample": "rectangular bar about 10 cm x 1 cm x 1 cm"
      },
      "method": "Heater-and-gradient measurement on a bar on an ADR cold stage, in the 2018 arXiv paper",
      "status": "ground",
      "uncertainty": "± 0.001",
      "source": "arxiv-ali-2018",
      "where": "Section 2.3 Thermal Conductivity, text: approximately 0.005±0.001 (W/m · K) at 300 mK",
      "source_detail": {
        "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
        "id": "arXiv:1807.03398",
        "url": "https://arxiv.org/pdf/1807.03398",
        "year": 2018,
        "kind": "paper",
        "license": "arXiv preprint (cited, not reproduced)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity of gold-plated CE7 at 300 mK (arXiv)",
      "value": 0.02,
      "bound": "exact",
      "unit": "W/m·K",
      "scope": "material",
      "conditions": {
        "temperature": "300 mK",
        "finish": "7 µm electroless nickel, then 3.8 µm soft gold"
      },
      "method": "Same bar type as the bare sample, electroplated with gold, in the 2018 arXiv paper",
      "status": "ground",
      "uncertainty": "± 0.005",
      "source": "arxiv-ali-2018",
      "where": "Section 2.3 Thermal Conductivity, text: 0.02±0.005 (W/m · K) at 300 mK for Au-plated CE7; plating in Section 3.2",
      "source_detail": {
        "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
        "id": "arXiv:1807.03398",
        "url": "https://arxiv.org/pdf/1807.03398",
        "year": 2018,
        "kind": "paper",
        "license": "arXiv preprint (cited, not reproduced)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity of gold-plated CE7 at 100 mK (arXiv)",
      "value": 0.006,
      "bound": "exact",
      "unit": "W/m·K",
      "scope": "material",
      "conditions": {
        "temperature": "100 mK",
        "finish": "7 µm electroless nickel, then 3.8 µm soft gold"
      },
      "method": "Same gold-plated bar as the 300 mK row, in the 2018 arXiv paper",
      "status": "ground",
      "uncertainty": "± 0.002",
      "source": "arxiv-ali-2018",
      "where": "Section 2.3 Thermal Conductivity, text: 0.006±0.002 (W/m · K) at 100 mK for Au-plated CE7",
      "source_detail": {
        "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
        "id": "arXiv:1807.03398",
        "url": "https://arxiv.org/pdf/1807.03398",
        "year": 2018,
        "kind": "paper",
        "license": "arXiv preprint (cited, not reproduced)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity at 25 °C (Microwave Journal 2003)",
      "value": 120,
      "bound": "exact",
      "unit": "W/mK",
      "scope": "material",
      "conditions": {
        "temperature": "25 °C",
        "grade": "CE7, Si-30% Al"
      },
      "method": "Value printed in the property table of a 2003 Osprey Metals article",
      "status": "ground",
      "source": "mwj-osprey-2003",
      "where": "Table 1 Key Properties, row Thermal conductivity at 25°C (W/mK), column CE7",
      "source_detail": {
        "title": "Osprey Metals, Controlled Expansion Alloys for High Reliability Packaging Solutions (Microwave Journal, article dated January 1, 2003)",
        "url": "https://www.microwavejournal.com/articles/3571-controlled-expansion-alloys-for-high-reliability-packaging-solutions",
        "year": 2003,
        "kind": "web",
        "license": "Trade journal article (cited, not reproduced)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity at 25.0 °C (LookPolymers record)",
      "value": 120,
      "bound": "exact",
      "unit": "W/m-K",
      "scope": "material",
      "conditions": {
        "temperature": "25.0 °C",
        "grade": "Si-30%Al"
      },
      "method": "Value printed in the Thermal Properties table of a MatWeb-format record",
      "status": "ground",
      "source": "lookpolymers-ce7",
      "where": "Thermal Properties table, row Thermal Conductivity, @Temperature 25.0 °C, value 120 W/m-K",
      "source_detail": {
        "title": "LookPolymers record: Osprey Metals CE7 Al-Si Controlled Expansion Alloy (MatWeb-format, information provided by Osprey Metals)",
        "url": "https://www.lookpolymers.com/polymer_Osprey-Metals-CE7-Al-Si-Controlled-Expansion-Alloy.php",
        "kind": "datasheet",
        "license": "Supplier record (cited, not reproduced)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity at 200 °C (LookPolymers record)",
      "value": 100,
      "bound": "exact",
      "unit": "W/m-K",
      "scope": "material",
      "conditions": {
        "temperature": "200 °C",
        "grade": "Si-30%Al"
      },
      "method": "Value printed in the Thermal Properties table of a MatWeb-format record",
      "status": "ground",
      "source": "lookpolymers-ce7",
      "where": "Thermal Properties table, row Thermal Conductivity, @Temperature 200 °C, value 100 W/m-K",
      "source_detail": {
        "title": "LookPolymers record: Osprey Metals CE7 Al-Si Controlled Expansion Alloy (MatWeb-format, information provided by Osprey Metals)",
        "url": "https://www.lookpolymers.com/polymer_Osprey-Metals-CE7-Al-Si-Controlled-Expansion-Alloy.php",
        "kind": "datasheet",
        "license": "Supplier record (cited, not reproduced)"
      }
    },
    {
      "benchmark": "specific_heat",
      "label": "Specific heat capacity (LookPolymers record)",
      "value": 0.75,
      "bound": "exact",
      "unit": "J/g-°C",
      "scope": "material",
      "conditions": {
        "temperature": "not stated in record",
        "grade": "Si-30%Al"
      },
      "method": "Value printed in the Specific Heat Capacity row of a MatWeb-format record",
      "status": "ground",
      "source": "lookpolymers-ce7",
      "where": "Thermal Properties table, row Specific Heat Capacity, value 0.750 J/g-°C",
      "source_detail": {
        "title": "LookPolymers record: Osprey Metals CE7 Al-Si Controlled Expansion Alloy (MatWeb-format, information provided by Osprey Metals)",
        "url": "https://www.lookpolymers.com/polymer_Osprey-Metals-CE7-Al-Si-Controlled-Expansion-Alloy.php",
        "kind": "datasheet",
        "license": "Supplier record (cited, not reproduced)"
      }
    },
    {
      "benchmark": "linear_contraction_300K_to_4K",
      "label": "Linear thermal contraction, 300 K to 4 K (upper limit, arXiv)",
      "value": 0.001,
      "bound": "upper",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "range": "300 K down to 4 K",
        "quantity": "fractional linear contraction (dimensionless)"
      },
      "method": "Strain gauge calibrated and epoxied to a 6.35 cm square CE7 sample, cooled to 4 K, in the 2018 arXiv paper",
      "status": "ground",
      "source": "arxiv-ali-2018",
      "where": "Section 2.2 Thermal Contraction, text: the fractional linear contraction was constrained to be less than 0.001",
      "source_detail": {
        "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
        "id": "arXiv:1807.03398",
        "url": "https://arxiv.org/pdf/1807.03398",
        "year": 2018,
        "kind": "paper",
        "license": "arXiv preprint (cited, not reproduced)"
      }
    }
  ],
  "corrosion": [],
  "risks": {
    "hazards": [
      {
        "text": "Osprey says the CE alloys are environmentally friendly, safe to handle and use, and present no disposal problems. This is the maker's own statement. No safety data sheet for CE7 was read in this run.",
        "ghs": [],
        "source": "mwj-osprey-2003",
        "where": "Main Attributes section, paragraph on environmental and handling properties"
      },
      {
        "text": "PubChem's aggregated ECHA C&L record for silicon (CID 5461123) says it does not meet GHS hazard criteria for 96.3% (3142 of 3263) of all reports. 11 notifications from 121 of 3263 reports give H228 (flammable solid) and H320 (causes eye irritation); the record does not say which physical form each notification covers. These codes describe the element, not the CE7 alloy.",
        "ghs": [
          "H228",
          "H320"
        ],
        "source": "pubchem-silicon",
        "where": "Safety and Hazards, GHS Classification (aggregated ECHA C&L notification summary)"
      },
      {
        "text": "PubChem's aggregated ECHA C&L record for aluminum (CID 5359268) covers 4079 reports. Of these, 338 (8.3%) say the chemical does not meet GHS hazard criteria. Among reports that give codes, H261 (in contact with water releases flammable gas) is given in 90.8%, H228 (flammable solid) in 60.6% and H250 (catches fire spontaneously if exposed to air) in 34.2%. Single notifications also list H370 and H372 (damage to organs). The record does not separate powder from bulk metal, so these codes are not read as the CE7 alloy's own.",
        "ghs": [
          "H261",
          "H228",
          "H250"
        ],
        "source": "pubchem-aluminum",
        "where": "Safety and Hazards, GHS Classification (aggregated ECHA C&L summary, percentages in parentheses)"
      }
    ],
    "failure_risks": [
      {
        "mode": "Brittle fracture with little plastic deformation",
        "consequence": "The paper reads the similar yield and ultimate strengths of CE7 as a sign of brittleness with minimal plastic deformation, a property inherited from silicon.",
        "source": "arxiv-ali-2018",
        "where": "Table 1 caption and the text after Table 1"
      },
      {
        "mode": "Fracture at grain boundaries during machining",
        "consequence": "Structures near the grain size are typically difficult to machine because fractures occur at grain boundaries. Parts were still produced to a surface finish better than 0.4 µm.",
        "source": "arxiv-ali-2018",
        "where": "Section 3.4 Fabrication"
      }
    ],
    "side_effects": [],
    "handling": [
      {
        "text": "Machine with carbide or polycrystalline diamond tools to a fine finish of 0.5 µm. Recesses, pedestals, holes, slots and tabs machine readily.",
        "source": "mwj-osprey-2003",
        "where": "Section Applications, paragraph on machining"
      },
      {
        "text": "In the CE7 grade, EDM tapping or threaded inserts may be desirable for tapped holes.",
        "source": "mwj-osprey-2003",
        "where": "Section on machining, after Table 1"
      },
      {
        "text": "Gold-plate parts for cryogenic thermal contact: the 2018 team used 7 µm electroless nickel, then 3.8 µm soft gold, because bare CE7 conducts heat poorly.",
        "source": "arxiv-ali-2018",
        "where": "Section 3.2 Thermal Conductivity and Gold Plating"
      }
    ],
    "mitigations": [
      {
        "text": "Gold plating raised the measured thermal conductivity at 300 mK from 0.005 to 0.02 W/m·K in the 2018 tests.",
        "source": "arxiv-ali-2018",
        "where": "Section 2.3 text, bare and Au-plated values at 300 mK"
      }
    ]
  },
  "uses": [
    {
      "application": "electronics-and-chips",
      "device": "RF and microwave flanges, light-weight carriers and packages",
      "example": "Osprey lists CE7 for RF/microwave flanges, light-weight carriers and packages, for its expansion match to circuit boards and components.",
      "source": "mwj-osprey-2003",
      "where": "Table 2 Properties Tailored to Applications, first row"
    },
    {
      "application": "optics-and-cameras",
      "device": "Millimetre-wave detector interface plates and feedhorn arrays for the 93 GHz CLASS telescopes",
      "example": "CE7 baseplates are deployed in the 93 GHz polarimetric focal planes of the Cosmology Large Angular Scale Surveyor (CLASS), and a 91-element CE7 feedhorn array was machined.",
      "source": "arxiv-ali-2018",
      "where": "Abstract; Section 3 text on CLASS interface plates; Figure 5 caption (91-element CE7 feedhorn array)"
    },
    {
      "application": "thermal-control",
      "device": "Heat sinks for power modules and discrete devices",
      "example": "Osprey names heat sinks for power modules and discrete devices as an important application area for its CE alloys.",
      "source": "mwj-osprey-2003",
      "where": "Applications section, paragraph beginning Another important application area"
    }
  ],
  "supply": [
    {
      "subject": "Silicon (the main element of CE7), read from silicon materials production",
      "abundance": "World and domestic resources for making silicon metal and alloys are abundant (USGS).",
      "producers": [
        {
          "country": "China",
          "share_percent": 80,
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "USGS 2025 Final List of Critical Minerals (silicon added, Federal Register 7 Nov 2025)",
          "listed": true
        }
      ],
      "substitutes": [
        "Gallium arsenide and germanium are the principal substitutes for silicon in semiconductor and infrared applications (USGS)."
      ],
      "source": "usgs-mcs2026-silicon",
      "where": "Events, Trends, and Issues: China accounted for almost 80% of total global estimated production of silicon materials in 2025 (printed as almost 80%); Critical minerals paragraph; World Resources and Substitutes sections"
    },
    {
      "subject": "Aluminium (about 30 % of CE7 by weight), read from the USGS aluminum summary",
      "abundance": "USGS 2026 prints world smelter production of 74,000 thousand metric tons in 2025e (rounded), of which China 45,000 thousand metric tons. In 2025 about 56% of aluminum recovered from purchased US scrap came from new scrap and 44% from old scrap.",
      "producers": [],
      "critical_lists": [],
      "substitutes": [],
      "source": "usgs-mcs2026-aluminum",
      "where": "World Smelter Production and Capacity table, column Smelter production 2025e (China and World total, rounded); Recycling paragraph"
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications (arXiv:1807.03398)",
      "type": "paper",
      "url": "https://arxiv.org/pdf/1807.03398",
      "year": 2018
    },
    {
      "title": "Osprey Metals, Controlled Expansion Alloys for High Reliability Packaging Solutions (Microwave Journal, article dated January 1, 2003)",
      "type": "datasheet",
      "url": "https://www.microwavejournal.com/articles/3571-controlled-expansion-alloys-for-high-reliability-packaging-solutions",
      "year": 2003
    },
    {
      "title": "Osprey Atomiqs materials list, controlled expansion alloys (entry Osprey CE7F)",
      "type": "datasheet",
      "url": "https://www.ospreyatomiqs.com/materials"
    },
    {
      "title": "LookPolymers record: Osprey Metals CE7 Al-Si Controlled Expansion Alloy (MatWeb-format, information provided by Osprey Metals)",
      "type": "datasheet",
      "url": "https://www.lookpolymers.com/polymer_Osprey-Metals-CE7-Al-Si-Controlled-Expansion-Alloy.php"
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026: Silicon",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-silicon.pdf",
      "year": 2026
    },
    {
      "title": "PubChem compound record: Silicon (CID 5461123), GHS Classification",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/Silicon"
    },
    {
      "title": "PubChem compound record: Aluminum (CID 5359268), GHS Classification",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/Aluminum"
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026: Aluminum",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-aluminum.pdf",
      "year": 2026
    }
  ],
  "gaps": [
    "No corrosion, humidity, salt-spray or ageing test result for CE7 was found in any source read. The corrosion list is empty.",
    "No flight, spacecraft or launch record for CE7 was found. The 2018 paper describes ground cryogenic telescopes (CLASS) only.",
    "No CE7 safety data sheet was read. The maker's safe-handling claim is kept, and PubChem GHS records for the elements silicon and aluminum are added as hazard entries. Those records describe the elements and their forms, not the CE7 alloy.",
    "The USGS 2026 aluminum summary, read in this run, prints no critical-minerals listing, so no critical list is recorded for aluminium.",
    "The USGS 2026 aluminum summary prints no producer shares as percentages, so no aluminium producer shares are recorded. The printed 2025e tonnages are kept in the supply abundance text.",
    "No images, drawings or other media were recorded for CE7 in this run.",
    "The 2003 Microwave Journal table prints a CE7 density of 2.40 with the unit printed as g/cm with a superscript 2 (g/cm2). The unit is not recorded because it is printed in a non-standard form, so the density value is left out.",
    "The 2018 paper's Table 1 prints the thermal conductivity of CE7 at 300 mK as 0.02, while its text gives 0.005 for bare CE7. Both text values are recorded; the table row is not recorded separately because it matches the gold-plated value.",
    "The 2018 paper's Table 1 prints the contraction from 293 K to 1 K as <10 with a x10^4 factor. Exponent-style values are not recorded, so this row is left out. The paper's predicted value of about .0012 is also left out.",
    "Young's modulus differs by source: 129.2 GPa (arXiv Table 1), 125 GPa (LookPolymers) and 120 GPa (Microwave Journal 2003). All three are kept as separate rows, not averaged.",
    "The shear modulus differs: 51.6 GPa (arXiv Table 1) and 50.0 GPa (LookPolymers, marked Calculated). Both are kept.",
    "The room-temperature expansion (7.2 ppm/°C, Osprey listing) and the 25 °C to 500 °C expansion (7.5 ppm/°C, Microwave Journal; 7.70 µm/m-°C, LookPolymers) are different tests. All are kept side by side.",
    "The ultimate tensile strength (about 100 MPa) is printed lower than the yield strength (110 MPa) in the arXiv Table 1. Both are kept as printed, and the paper calls the two similar.",
    "Density: 2.43 g/cm3 (arXiv Table 1) and 2.43 g/cc (Osprey listing) agree. The CE7 composition basis is given as wt % in the 2003 article only.",
    "The meaning of the F suffix in CE7F is not printed in any source read. The older name CE7 is used in the 2003 article and the 2018 paper.",
    "The LookPolymers record prints a Vickers hardness of 255 with no unit, so it is not recorded.",
    "No tempers, heat treatments or form (cast, sprayed or machined) are printed for the mechanical values. The paper measured its sample, and the form is not stated.",
    "The superconducting critical temperature and linear contraction benchmarks are not in property-canon.yaml. Short snake_case names are used for them.",
    "Aluminium supply is covered by the aluminium-alloy profiles and is not repeated here. The supply entry covers silicon only, using USGS 2026 printed figures.",
    "No space-environment data (outgassing, radiation or thermal cycling in orbit) were found in the sources read."
  ],
  "story": {
    "why": "Semiconductors and ceramic circuit boards are relatively fragile, so a package material whose expansion is close to theirs keeps them in slight compression over the whole service range (Microwave Journal, 2003). CE7 is Osprey's silicon-aluminium alloy built for that job. Its expansion of 7.5 ppm/°C from 25 °C to 500 °C is close to that of gallium arsenide and alumina, as the 2003 article states. The 2018 arXiv paper added cryogenic tests: CE7 superconducts at 1.190 K and conducts heat poorly at 300 mK.",
    "uses": [
      {
        "where": "RF and microwave packages",
        "line": "Osprey lists CE7 for RF/microwave flanges, light-weight carriers and packages, because its expansion matches circuit boards and components (Microwave Journal, 2003)."
      },
      {
        "where": "Cryogenic millimetre-wave detectors",
        "line": "CE7 baseplates are deployed in the 93 GHz polarimetric focal planes of CLASS, and a 91-element CE7 feedhorn array was machined (arXiv 2018)."
      }
    ],
    "can_do": [
      {
        "label": "Match thermal expansion",
        "line": "Osprey gives 7.5 ppm/°C from 25 °C to 500 °C in its 2003 article, and 7.2 ppm/°C at room temperature on its current listing.",
        "benchmark": "cte",
        "scope": "material",
        "value": "7.5 ppm/°C (2003); 7.2 ppm/°C (current listing)"
      },
      {
        "label": "Low density",
        "line": "Osprey's current listing and the 2018 arXiv paper both give a density of 2.43 g/cc.",
        "benchmark": "density",
        "scope": "material",
        "value": "2.43 g/cc"
      },
      {
        "label": "Superconduct at low temperature",
        "line": "The 2018 arXiv paper measured a critical temperature of 1.190 K, with an uncertainty of ± .005 K as printed.",
        "benchmark": "superconducting_critical_temperature",
        "scope": "material",
        "value": "1.190 K"
      },
      {
        "label": "Fine machined finish",
        "line": "Osprey gives a finish of 0.5 µm with carbide or polycrystalline diamond tools.",
        "scope": "material",
        "value": "0.5 µm"
      }
    ],
    "compare": "The sources read do not compare CE7 numerically with other grades in this collection. The 2003 Microwave Journal article ranks CE7 among its CE alloys by expansion, and says its expansion matches gallium arsenide and alumina fairly closely. The 2018 arXiv paper compares CE7 with silicon, aluminium, copper and alumina in its Table 1, but no values for those other materials are recorded here, so no numerical comparison is made.",
    "compare_rows": [
      {
        "label": "Thermal expansion (CTE)",
        "benchmark": "cte",
        "scope": "material"
      },
      {
        "label": "Density",
        "benchmark": "density",
        "scope": "material"
      },
      {
        "label": "Thermal conductivity",
        "benchmark": "thermal_conductivity",
        "scope": "material"
      }
    ],
    "handling": [
      "Machine with carbide or polycrystalline diamond tools to a finish of 0.5 µm (Microwave Journal, 2003).",
      "Use EDM tapping or threaded inserts for tapped holes in CE7, as the 2003 article suggests.",
      "Gold-plate parts for cryogenic thermal contact with 7 µm electroless nickel and 3.8 µm soft gold (arXiv 2018)."
    ],
    "good_for": [
      "Machined housings, flanges and carriers for silicon and gallium arsenide microwave parts that need an expansion close to the part (Microwave Journal, 2003).",
      "Cryogenic millimetre-wave detector interface plates and feedhorn arrays, as used in the 93 GHz CLASS focal planes (arXiv 2018)."
    ],
    "watch_out": [
      "Brittle: yield (110 MPa) and ultimate tensile strength (about 100 MPa) are nearly the same in the 2018 table.",
      "Poor thermal conduction at cryogenic temperatures: 0.005 W/m·K when bare at 300 mK, so the 2018 team gold plated the parts.",
      "Sources disagree on density, Young's modulus, shear modulus and expansion. Each value is kept with its own source, and none is averaged.",
      "No flight, spacecraft, corrosion or safety data sheet was found in the sources read."
    ],
    "verdict": "CE7 is a silicon-aluminium alloy with expansion, density and cryogenic data from its maker and a 2018 cryogenic test paper. It is brittle, and the sources read give no flight record and no corrosion data.",
    "recipe": {
      "line": "CE7 is a binary silicon-aluminium alloy, not a powder composite. Osprey makes its controlled expansion alloys by a patented spray-forming process (Microwave Journal, 2003). The 2018 paper describes interwoven continuous silicon and aluminium phases.",
      "parts": [
        {
          "name": "Silicon",
          "symbol": "Si",
          "role": "Main phase. It keeps the expansion and density low (LookPolymers composition; arXiv 2018 text).",
          "share_percent": 70,
          "source": "lookpolymers-ce7",
          "where": "Component Elements Properties table, row Silicon Si, value 70 %"
        },
        {
          "name": "Aluminium",
          "symbol": "Al",
          "role": "Second continuous phase. The 2018 paper says the aluminium makes CE7 contract more than silicon does.",
          "share_percent": 30,
          "source": "mwj-osprey-2003",
          "where": "Table 1 Key Properties, row Composition (wt %), column CE7 (printed Si-30% Al)"
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "No safety data sheet for CE7 was read. The hazard data are the maker's claim and PubChem GHS records for the elements silicon and aluminum.",
        "points": [
          {
            "label": "Maker's claim",
            "line": "Osprey says the alloys are safe to handle and use and present no disposal problems (Microwave Journal, 2003)."
          },
          {
            "label": "Element records",
            "line": "PubChem lists H228 (flammable solid) for some silicon and aluminum notifications, and H261 (releases flammable gas in contact with water) for aluminum, but does not say which physical form each notification covers."
          }
        ],
        "verdict": "Maker says safe; no CE7 SDS read; element records list codes"
      },
      {
        "title": "If it fails",
        "lead": "The sources describe brittleness rather than failure rates.",
        "points": [
          {
            "label": "Brittleness",
            "line": "Yield and ultimate tensile strength are nearly the same, so the alloy shows little plastic deformation before it breaks (arXiv 2018)."
          },
          {
            "label": "Grain boundaries",
            "line": "Machining near the grain size causes fractures at grain boundaries (arXiv 2018)."
          }
        ],
        "verdict": "Brittle; no failure-rate data"
      },
      {
        "title": "Handling and cooling",
        "lead": "The sources give machining and plating steps, not hazards.",
        "points": [
          {
            "label": "Plating",
            "line": "Bare CE7 conducts heat poorly at 300 mK, so the 2018 parts were gold plated (arXiv 2018)."
          }
        ],
        "verdict": "Plate for cryogenic use"
      }
    ]
  },
  "updated": "2026-11-02",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 27,
    "unreachable": 0,
    "caveats": 6,
    "note": "Values were read by an AI assistant on 2026-11-01 from the pages named in each entry. Sources disagree on density, Young's modulus, shear modulus, thermal expansion and thermal conductivity; each value is kept with its own source. The CE7 mechanical values come from a 2018 paper that credits Sandvik Osprey measurements. No flight, corrosion or SDS data were found."
  },
  "sources": {
    "arxiv-ali-2018": {
      "title": "Ali et al. 2018, SiAl Alloy Feedhorn Arrays: Material Properties, Feedhorn Design, and Astrophysical Applications",
      "id": "arXiv:1807.03398",
      "url": "https://arxiv.org/pdf/1807.03398",
      "year": 2018,
      "kind": "paper",
      "license": "arXiv preprint (cited, not reproduced)"
    },
    "mwj-osprey-2003": {
      "title": "Osprey Metals, Controlled Expansion Alloys for High Reliability Packaging Solutions (Microwave Journal, article dated January 1, 2003)",
      "url": "https://www.microwavejournal.com/articles/3571-controlled-expansion-alloys-for-high-reliability-packaging-solutions",
      "year": 2003,
      "kind": "web",
      "license": "Trade journal article (cited, not reproduced)"
    },
    "ospreyatomiqs-materials": {
      "title": "Osprey Atomiqs materials list, controlled expansion alloys (entry Osprey CE7F)",
      "url": "https://www.ospreyatomiqs.com/materials",
      "kind": "datasheet",
      "license": "Manufacturer materials listing (cited, not reproduced)"
    },
    "lookpolymers-ce7": {
      "title": "LookPolymers record: Osprey Metals CE7 Al-Si Controlled Expansion Alloy (MatWeb-format, information provided by Osprey Metals)",
      "url": "https://www.lookpolymers.com/polymer_Osprey-Metals-CE7-Al-Si-Controlled-Expansion-Alloy.php",
      "kind": "datasheet",
      "license": "Supplier record (cited, not reproduced)"
    },
    "usgs-mcs2026-silicon": {
      "title": "USGS Mineral Commodity Summaries 2026: Silicon",
      "id": "USGS MCS 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-silicon.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "pubchem-silicon": {
      "title": "PubChem compound record: Silicon (CID 5461123), Safety and Hazards, GHS Classification",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/Silicon",
      "kind": "database",
      "license": "Public database record (cited, not reproduced)"
    },
    "pubchem-aluminum": {
      "title": "PubChem compound record: Aluminum (CID 5359268), Safety and Hazards, GHS Classification",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/Aluminum",
      "kind": "database",
      "license": "Public database record (cited, not reproduced)"
    },
    "usgs-mcs2026-aluminum": {
      "title": "USGS Mineral Commodity Summaries 2026: Aluminum",
      "id": "USGS MCS 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-aluminum.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/aluminium-silicon-ce7/"
}