{
  "spore": "profile",
  "id": "hextow-im7",
  "spore_version": "0.2",
  "family": "carbon-materials",
  "name": "Hexcel HexTow IM7 carbon fibre",
  "abbreviation": "IM7",
  "role": "reinforcing fibre (intermediate-modulus carbon fibre)",
  "category": "carbon",
  "type": "carbon-fiber",
  "summary": "HexTow IM7 is Hexcel's intermediate-modulus, PAN-based carbon fibre, supplied as 12K continuous tows. Hexcel's IM7 datasheet prints a typical tensile strength of 5670 MPa and a tensile modulus of 276 GPa, with a density of 1.78 g/cm3 and an ultimate elongation of 1.8%. Hexcel states that IM7-G 12K (0.25%) has been qualified to NMS 818 Carbon Fiber Specification (NCAMP); we did not confirm that qualification in an NCAMP document. Laminate values for IM7 in HexPly 8552 resin belong to the prepreg profile (im7-8552) and are not recorded here.\n",
  "best_for": "Structural composites that need more stiffness and strength than a standard-modulus fibre such as AS4 (Hexcel selector guide)",
  "weakest_at": "Low strain at failure (1.8% per Hexcel), and no fibre-only compression, fatigue or space-exposure data in the sources read",
  "identity": {
    "formula": "C (PAN-based carbon fibre, 95.0% carbon content per the Hexcel datasheet)",
    "designations": [],
    "source": "hexcel-im7-datasheet",
    "where": "Title block and Typical Fiber Properties table (Carbon Content row)"
  },
  "tags": {
    "environments": [],
    "stresses": [],
    "applications": [
      "structures"
    ]
  },
  "properties": [
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength, HexTow IM7 fibre (typical)",
      "value": 5670,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "continuous HexTow IM7 tow",
        "basis": "typical fibre property; Hexcel calls its performance values representative, not guaranteed"
      },
      "method": "Manufacturer typical value printed on Hexcel's IM7 product data sheet",
      "status": "ground",
      "note": "The same row prints 820 ksi in U.S. units.",
      "source": "hexcel-im7-datasheet",
      "where": "Typical Fiber Properties table, Tensile Strength row, SI Units column",
      "source_detail": {
        "title": "HexTow IM7 Carbon Fiber Product Data Sheet (Hexcel Corporation, copyright 2023, CTA 351 AG23)",
        "id": "Hexcel CTA 351 AG23; the same file is also served at wp-content/uploads/2026/01/IM7_HexTow_DataSheet.pdf",
        "url": "https://www.hexcel.com/wp-content/uploads/2025/12/IM7_HexTow_DataSheet.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Tensile modulus, HexTow IM7 fibre (typical)",
      "value": 276,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "form": "continuous HexTow IM7 tow",
        "test_basis": "printed as Tensile Modulus (Chord 6000-1000); the same row prints 40.0 Msi"
      },
      "method": "Manufacturer typical value on Hexcel's datasheet; modulus is a chord between 6000 and 1000 as printed on the datasheet",
      "status": "ground",
      "source": "hexcel-im7-datasheet",
      "where": "Typical Fiber Properties table, Tensile Modulus row, SI Units column",
      "source_detail": {
        "title": "HexTow IM7 Carbon Fiber Product Data Sheet (Hexcel Corporation, copyright 2023, CTA 351 AG23)",
        "id": "Hexcel CTA 351 AG23; the same file is also served at wp-content/uploads/2026/01/IM7_HexTow_DataSheet.pdf",
        "url": "https://www.hexcel.com/wp-content/uploads/2025/12/IM7_HexTow_DataSheet.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Ultimate elongation at failure, HexTow IM7 fibre",
      "value": 1.8,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "form": "continuous HexTow IM7 tow",
        "basis": "typical fibre property"
      },
      "method": "Manufacturer typical value on Hexcel's datasheet",
      "status": "ground",
      "source": "hexcel-im7-datasheet",
      "where": "Typical Fiber Properties table, Ultimate Elongation at Failure row",
      "source_detail": {
        "title": "HexTow IM7 Carbon Fiber Product Data Sheet (Hexcel Corporation, copyright 2023, CTA 351 AG23)",
        "id": "Hexcel CTA 351 AG23; the same file is also served at wp-content/uploads/2026/01/IM7_HexTow_DataSheet.pdf",
        "url": "https://www.hexcel.com/wp-content/uploads/2025/12/IM7_HexTow_DataSheet.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "density",
      "label": "Density, HexTow IM7 fibre",
      "value": 1.78,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "form": "continuous HexTow IM7 tow",
        "basis": "typical fibre property"
      },
      "method": "Manufacturer typical value on Hexcel's datasheet",
      "status": "ground",
      "note": "The same row prints 0.0643 lb/in3 in U.S. units. The selector guide prints 1.78 g/cm3 for IM7 too.",
      "source": "hexcel-im7-datasheet",
      "where": "Typical Fiber Properties table, Density row, SI Units column",
      "source_detail": {
        "title": "HexTow IM7 Carbon Fiber Product Data Sheet (Hexcel Corporation, copyright 2023, CTA 351 AG23)",
        "id": "Hexcel CTA 351 AG23; the same file is also served at wp-content/uploads/2026/01/IM7_HexTow_DataSheet.pdf",
        "url": "https://www.hexcel.com/wp-content/uploads/2025/12/IM7_HexTow_DataSheet.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "carbon_content",
      "label": "Carbon content, HexTow IM7 fibre",
      "value": 95,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "form": "continuous HexTow IM7 tow",
        "basis": "typical fibre property"
      },
      "method": "Manufacturer typical value on Hexcel's datasheet",
      "status": "ground",
      "source": "hexcel-im7-datasheet",
      "where": "Typical Fiber Properties table, Carbon Content row",
      "source_detail": {
        "title": "HexTow IM7 Carbon Fiber Product Data Sheet (Hexcel Corporation, copyright 2023, CTA 351 AG23)",
        "id": "Hexcel CTA 351 AG23; the same file is also served at wp-content/uploads/2026/01/IM7_HexTow_DataSheet.pdf",
        "url": "https://www.hexcel.com/wp-content/uploads/2025/12/IM7_HexTow_DataSheet.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "linear_density",
      "label": "Weight per length, 12K HexTow IM7 tow",
      "value": 0.446,
      "bound": "exact",
      "unit": "g/m",
      "scope": "material",
      "conditions": {
        "form": "12K tow (12,000 filaments), as printed",
        "basis": "typical fibre property"
      },
      "method": "Manufacturer typical value on Hexcel's datasheet",
      "status": "ground",
      "source": "hexcel-im7-datasheet",
      "where": "Typical Fiber Properties table, Weight/Length 12K row, SI Units column",
      "source_detail": {
        "title": "HexTow IM7 Carbon Fiber Product Data Sheet (Hexcel Corporation, copyright 2023, CTA 351 AG23)",
        "id": "Hexcel CTA 351 AG23; the same file is also served at wp-content/uploads/2026/01/IM7_HexTow_DataSheet.pdf",
        "url": "https://www.hexcel.com/wp-content/uploads/2025/12/IM7_HexTow_DataSheet.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "filament_diameter",
      "label": "Filament diameter, HexTow IM7 fibre",
      "value": 5.2,
      "bound": "exact",
      "unit": "microns",
      "scope": "material",
      "conditions": {
        "form": "individual filament in the tow",
        "basis": "typical fibre property"
      },
      "method": "Manufacturer typical value on Hexcel's datasheet",
      "status": "ground",
      "note": "The same row prints 0.203 mil in U.S. units.",
      "source": "hexcel-im7-datasheet",
      "where": "Typical Fiber Properties table, Filament Diameter row, SI Units column",
      "source_detail": {
        "title": "HexTow IM7 Carbon Fiber Product Data Sheet (Hexcel Corporation, copyright 2023, CTA 351 AG23)",
        "id": "Hexcel CTA 351 AG23; the same file is also served at wp-content/uploads/2026/01/IM7_HexTow_DataSheet.pdf",
        "url": "https://www.hexcel.com/wp-content/uploads/2025/12/IM7_HexTow_DataSheet.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity, HexTow IM7 yarn",
      "value": 5.4,
      "bound": "exact",
      "unit": "W/m-ºK",
      "scope": "material",
      "conditions": {
        "form": "yarn/tow",
        "direction": "not stated in the datasheet"
      },
      "method": "Manufacturer value on Hexcel's datasheet",
      "status": "ground",
      "note": "The same row prints 3.12 Btu/hr-ft-ºF in U.S. units.",
      "source": "hexcel-im7-datasheet",
      "where": "Yarn/Tow Characteristics table, Thermal Conductivity row, SI Units column",
      "source_detail": {
        "title": "HexTow IM7 Carbon Fiber Product Data Sheet (Hexcel Corporation, copyright 2023, CTA 351 AG23)",
        "id": "Hexcel CTA 351 AG23; the same file is also served at wp-content/uploads/2026/01/IM7_HexTow_DataSheet.pdf",
        "url": "https://www.hexcel.com/wp-content/uploads/2025/12/IM7_HexTow_DataSheet.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "cte",
      "label": "Coefficient of thermal expansion, HexTow IM7 yarn",
      "value": -0.64,
      "bound": "exact",
      "unit": "ppm/ºC",
      "scope": "material",
      "conditions": {
        "form": "yarn/tow",
        "direction": "not stated in the datasheet"
      },
      "method": "Manufacturer value on Hexcel's datasheet",
      "status": "ground",
      "note": "The same row prints -0.36 ppm/ºF in U.S. units.",
      "source": "hexcel-im7-datasheet",
      "where": "Yarn/Tow Characteristics table, Coefficient of Thermal Expansion row, SI Units column",
      "source_detail": {
        "title": "HexTow IM7 Carbon Fiber Product Data Sheet (Hexcel Corporation, copyright 2023, CTA 351 AG23)",
        "id": "Hexcel CTA 351 AG23; the same file is also served at wp-content/uploads/2026/01/IM7_HexTow_DataSheet.pdf",
        "url": "https://www.hexcel.com/wp-content/uploads/2025/12/IM7_HexTow_DataSheet.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "specific_heat",
      "label": "Specific heat, HexTow IM7 yarn",
      "value": 0.21,
      "bound": "exact",
      "unit": "cal/g-°C",
      "scope": "material",
      "conditions": {
        "form": "yarn/tow"
      },
      "method": "Manufacturer value on Hexcel's datasheet",
      "status": "ground",
      "note": "The same row prints 0.21 Btu/lb-°F in U.S. units.",
      "source": "hexcel-im7-datasheet",
      "where": "Yarn/Tow Characteristics table, Specific Heat row, SI Units column",
      "source_detail": {
        "title": "HexTow IM7 Carbon Fiber Product Data Sheet (Hexcel Corporation, copyright 2023, CTA 351 AG23)",
        "id": "Hexcel CTA 351 AG23; the same file is also served at wp-content/uploads/2026/01/IM7_HexTow_DataSheet.pdf",
        "url": "https://www.hexcel.com/wp-content/uploads/2025/12/IM7_HexTow_DataSheet.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Comparison - tensile strength, HexTow IM8 fibre (typical)",
      "value": 6170,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "continuous HexTow IM8 tow",
        "basis": "typical fibre property; comparator, not IM7"
      },
      "method": "Manufacturer typical value on Hexcel's IM8 product data sheet",
      "status": "ground",
      "note": "The same row prints 895 ksi in U.S. units.",
      "source": "hexcel-im8-datasheet",
      "where": "Typical Fiber Properties table, Tensile Strength row, SI Units column",
      "source_detail": {
        "title": "HexTow IM8 Carbon Fiber Product Data Sheet (Hexcel Corporation)",
        "id": "Hexcel CTA IM8 product data sheet, copyright 2023",
        "url": "https://hexcel.com/wp-content/uploads/2026/01/IM8_HexTow_DataSheet.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Comparison - tensile modulus, HexTow IM8 fibre (typical)",
      "value": 304,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "form": "continuous HexTow IM8 tow",
        "test_basis": "printed as Tensile Modulus (Chord 6000-1000); comparator, not IM7"
      },
      "method": "Manufacturer typical value on Hexcel's IM8 product data sheet",
      "status": "ground",
      "source": "hexcel-im8-datasheet",
      "where": "Typical Fiber Properties table, Tensile Modulus row, SI Units column",
      "source_detail": {
        "title": "HexTow IM8 Carbon Fiber Product Data Sheet (Hexcel Corporation)",
        "id": "Hexcel CTA IM8 product data sheet, copyright 2023",
        "url": "https://hexcel.com/wp-content/uploads/2026/01/IM8_HexTow_DataSheet.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Comparison - tensile strength, HexTow IM6 fibre (typical, 12K)",
      "value": 5860,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "12K HexTow IM6 tow",
        "basis": "typical fibre property; comparator, not IM7"
      },
      "method": "Manufacturer typical value on Hexcel's IM6 product data sheet",
      "status": "ground",
      "note": "The same row prints 850 ksi in U.S. units.",
      "source": "hexcel-im6-datasheet",
      "where": "Typical Fiber Properties table, Tensile Strength (12K) row, SI Units column",
      "source_detail": {
        "title": "HexTow IM6 Carbon Fiber Product Data Sheet (Hexcel Corporation)",
        "id": "Hexcel IM6 product data sheet (upload path 2025/12)",
        "url": "https://hexcel.com/wp-content/uploads/2025/12/IM6_HexTow_DataSheet.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Comparison - tensile modulus, HexTow IM6 fibre (typical)",
      "value": 279,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "form": "continuous HexTow IM6 tow",
        "test_basis": "printed as Tensile Modulus (Chord 6000-1000); comparator, not IM7"
      },
      "method": "Manufacturer typical value on Hexcel's IM6 product data sheet",
      "status": "ground",
      "source": "hexcel-im6-datasheet",
      "where": "Typical Fiber Properties table, Tensile Modulus row, SI Units column",
      "source_detail": {
        "title": "HexTow IM6 Carbon Fiber Product Data Sheet (Hexcel Corporation)",
        "id": "Hexcel IM6 product data sheet (upload path 2025/12)",
        "url": "https://hexcel.com/wp-content/uploads/2025/12/IM6_HexTow_DataSheet.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Comparison - tensile strength, HexTow AS7 fibre (typical)",
      "value": 4930,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "continuous HexTow AS7 tow",
        "basis": "typical fibre property; comparator, not IM7"
      },
      "method": "Manufacturer typical value on Hexcel's AS7 product data sheet",
      "status": "ground",
      "note": "The same row prints 715 ksi in U.S. units.",
      "source": "hexcel-as7-datasheet",
      "where": "Typical Fiber Properties table, Tensile Strength row, SI Units column",
      "source_detail": {
        "title": "HexTow AS7 Carbon Fiber Product Data Sheet (Hexcel Corporation)",
        "id": "Hexcel AS7 product data sheet (upload path 2025/12)",
        "url": "https://hexcel.com/wp-content/uploads/2025/12/AS7_Aerospace_HexTow_DataSheet.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Comparison - tensile modulus, HexTow AS7 fibre (typical)",
      "value": 243,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "form": "continuous HexTow AS7 tow",
        "test_basis": "printed as Tensile Modulus (Chord 6000-1000); comparator, not IM7"
      },
      "method": "Manufacturer typical value on Hexcel's AS7 product data sheet",
      "status": "ground",
      "source": "hexcel-as7-datasheet",
      "where": "Typical Fiber Properties table, Tensile Modulus row, SI Units column",
      "source_detail": {
        "title": "HexTow AS7 Carbon Fiber Product Data Sheet (Hexcel Corporation)",
        "id": "Hexcel AS7 product data sheet (upload path 2025/12)",
        "url": "https://hexcel.com/wp-content/uploads/2025/12/AS7_Aerospace_HexTow_DataSheet.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "Hexcel data sheet, cited not reproduced"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Comparison - tensile strength, HexTow AS4 fibre (typical)",
      "value": 4501,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "continuous HexTow AS4 tow",
        "basis": "tow tensile strength from the aerospace-grade table; comparator, not IM7"
      },
      "method": "Manufacturer typical value in Hexcel's selector guide",
      "status": "ground",
      "note": "The same row prints 650 ksi.",
      "source": "hexcel-selector-guide",
      "where": "Aerospace-Grade HexTow Carbon Fiber table, AS4 row, Tensile Strength (MPa) column (page 2)",
      "source_detail": {
        "title": "HexTow Carbon Fiber: aerospace-grade and industrial-grade selector guide with composite properties (Hexcel, CTU 396 FB25)",
        "id": "Hexcel CTU 396 FB25, copyright 2025",
        "url": "https://www.hexcel.com/wp-content/uploads/2026/01/HexTowSelectorGuide.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "Hexcel brochure, cited not reproduced"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Comparison - tensile modulus, HexTow AS4 fibre (typical)",
      "value": 231,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "form": "continuous HexTow AS4 tow",
        "basis": "tow tensile modulus from the aerospace-grade table; comparator, not IM7"
      },
      "method": "Manufacturer typical value in Hexcel's selector guide",
      "status": "ground",
      "note": "The same row prints 33.5 Msi.",
      "source": "hexcel-selector-guide",
      "where": "Aerospace-Grade HexTow Carbon Fiber table, AS4 row, Tensile Modulus (GPa) column (page 2)",
      "source_detail": {
        "title": "HexTow Carbon Fiber: aerospace-grade and industrial-grade selector guide with composite properties (Hexcel, CTU 396 FB25)",
        "id": "Hexcel CTU 396 FB25, copyright 2025",
        "url": "https://www.hexcel.com/wp-content/uploads/2026/01/HexTowSelectorGuide.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "Hexcel brochure, cited not reproduced"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Storage of carbon fibre in warm or humid conditions (ageing rather than corrosion)",
      "headline": "Hexcel gives one year of constant properties for unsized fibre and five years for GP or GS sized fibre, if stored indoors below 35°C and below 50% relative humidity.",
      "effect": "Hexcel's storage guidance, which covers HexTow carbon fibre in general and does not list IM7 separately, says unsized fibre keeps its tow tensile strength, tow tensile modulus, tow tensile elongation and fibre density for at least one year from manufacture, and GP and GS sized fibre keeps them for at least five years. Fibre stored at high temperature or high humidity, or beyond the recommended time, may process badly, and Hexcel advises checking its processing (resin wet-out and spreadability) before use.",
      "rating": "low",
      "conditions": {
        "storage": "indoors, in original containers, below 35°C (95°F) and below 50% RH; shrink wrap kept on until use",
        "exposure": "high temperature or high humidity, or storage beyond the recommended time"
      },
      "source": "hexcel-selector-guide",
      "where": "Recommended Storage and Shelf Life panel, page 6"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "Hexcel's SDS for HexForce woven carbon fabric (revision 1.1, dated 8/10/2020) states the product is not hazardous under the OSHA Hazard Communication Standard, and rates its physical, health and environmental hazards as not classified. It is a woven-fabric SDS, not an IM7 tow SDS.",
        "ghs": [],
        "source": "hexforce-sds",
        "where": "Section 2, Classification of the substance or mixture"
      },
      {
        "text": "The same HexForce SDS warns of mild, temporary mechanical eye and skin irritation, and says fine dust clouds may form explosive mixtures with air.",
        "ghs": [],
        "source": "hexforce-sds",
        "where": "Section 2, Other hazards (hazards not otherwise classified)"
      },
      {
        "text": "Rave Scientific's SDS for high-purity carbon fibres in carbon fibre threads (version 4.0, dated October 5th 2022) says the substance does not meet the classification criteria of Regulation EC Nr. 1272/2008. It gives an EU occupational exposure limit of 10 mg/m3 TWA for carbon (C) fibres. That product is a carbon-coating thread, not IM7 tow.",
        "ghs": [],
        "source": "rave-sds",
        "where": "Section 2.1 and Section 8.1 (occupational exposure limits)"
      }
    ],
    "failure_risks": [
      {
        "mode": "Brittle fracture at low strain",
        "trigger": "Tensile loading of the fibre to failure",
        "consequence": "Hexcel lists an ultimate elongation at failure of 1.8% for IM7, so the fibre breaks after only a small stretch.",
        "severity": "moderate",
        "source": "hexcel-im7-datasheet",
        "where": "Typical Fiber Properties table, Ultimate Elongation at Failure row"
      },
      {
        "mode": "Loss of processing quality after poor storage",
        "trigger": "Storage above 35°C or above 50% relative humidity, or storage beyond the recommended time",
        "consequence": "Hexcel warns that difficulty in processing may result, and advises evaluating resin wet-out and spreadability before use.",
        "severity": "low",
        "source": "hexcel-selector-guide",
        "where": "Recommended Storage and Shelf Life panel, page 6"
      }
    ],
    "side_effects": [
      {
        "text": "Hexcel's HexForce SDS states that carbon fibre contained in some products is electrically conductive, and that fine dust clouds may form explosive mixtures with air.",
        "affects": "Electrical equipment near the fibre, and workers exposed to fine dust",
        "source": "hexforce-sds",
        "where": "Section 2, Physicochemical hazards and Other hazards"
      }
    ],
    "handling": [
      {
        "text": "Store indoors in the original container, below 35°C and below 50% relative humidity, with shrink wrap left on until use.",
        "source": "hexcel-selector-guide",
        "where": "Recommended Storage and Shelf Life panel, page 6"
      },
      {
        "text": "Avoid creating or accumulating dust. The Rave SDS advises avoiding dust and wearing safety goggles with side protection.",
        "source": "rave-sds",
        "where": "Sections 8.2 and 10.4"
      },
      {
        "text": "Obtain, read and understand the safety data sheet for your sizing before use, as Hexcel's datasheet instructs.",
        "source": "hexcel-im7-datasheet",
        "where": "Safety Information"
      }
    ],
    "mitigations": [
      {
        "text": "Use goggles with side protection when handling cut or abraded fibre, as the Rave SDS advises for carbon fibre threads.",
        "source": "rave-sds",
        "where": "Section 8.2 (personal protection)"
      }
    ]
  },
  "uses": [
    {
      "application": "structures",
      "device": "Aerospace structures using an aerospace-grade fibre",
      "example": "Hexcel's IM7 datasheet states that IM7-G 12K (0.25%) carbon fiber has been qualified to NMS 818 Carbon Fiber Specification (NCAMP), so customers can call out an industry standard, aerospace grade carbon fiber without writing their own specification.",
      "source": "hexcel-im7-datasheet",
      "where": "Page 1, second paragraph"
    },
    {
      "application": "structures",
      "device": "Formula 1 cars, competition racing boats and high-performance cars",
      "example": "Hexcel's selector guide says HexTow standard and intermediate modulus carbon fiber is selected for winning Formula 1 cars, competition racing boats, high-performance cars, and composite tooling material.",
      "source": "hexcel-selector-guide",
      "where": "Industrial-Grade HexTow Carbon Fiber panel, page 4"
    }
  ],
  "supply": [
    {
      "subject": "PAN precursor (polyacrylonitrile) for HexTow IM7",
      "abundance": "Not applicable: a synthetic fibre made from a polymer precursor, so no crustal abundance applies",
      "producers": [],
      "critical_lists": [],
      "recycling": "Not stated in the sources read.",
      "substitutes": [],
      "source": "wikipedia-carbon-fiber",
      "where": "Precursor paragraph of the article, which names 'polyacrylonitrile (PAN), rayon, or petroleum pitch' as precursors"
    },
    {
      "subject": "Hexcel HexTow IM7 manufacturing",
      "abundance": "Not stated",
      "producers": [],
      "critical_lists": [],
      "recycling": "Not stated in the sources read.",
      "substitutes": [],
      "source": "hexcel-im7-datasheet",
      "where": "Title block names Hexcel Corporation; the datasheet does not give a plant location or production share"
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "HexTow IM7 Carbon Fiber Product Data Sheet (Hexcel, 2023)",
      "type": "datasheet",
      "url": "https://www.hexcel.com/wp-content/uploads/2025/12/IM7_HexTow_DataSheet.pdf",
      "year": 2023
    },
    {
      "title": "HexTow Carbon Fiber selector guide and composite properties (Hexcel, CTU 396 FB25)",
      "type": "datasheet",
      "url": "https://www.hexcel.com/wp-content/uploads/2026/01/HexTowSelectorGuide.pdf",
      "year": 2025
    },
    {
      "title": "HexTow IM8 Carbon Fiber Product Data Sheet (Hexcel)",
      "type": "datasheet",
      "url": "https://hexcel.com/wp-content/uploads/2026/01/IM8_HexTow_DataSheet.pdf",
      "year": 2023
    },
    {
      "title": "HexTow AS7 Carbon Fiber Product Data Sheet (Hexcel)",
      "type": "datasheet",
      "url": "https://hexcel.com/wp-content/uploads/2025/12/AS7_Aerospace_HexTow_DataSheet.pdf",
      "year": 2025
    },
    {
      "title": "HexTow IM6 Carbon Fiber Product Data Sheet (Hexcel)",
      "type": "datasheet",
      "url": "https://hexcel.com/wp-content/uploads/2025/12/IM6_HexTow_DataSheet.pdf",
      "year": 2025
    },
    {
      "title": "Safety Data Sheet: High purity carbon fibers in carbon fiber threads (Rave Scientific, SDS00170CC1016 v4.0)",
      "type": "sds",
      "url": "https://ravescientific.com/images/pdf/SDS00170CC1016-01_Carbon_Fibre.pdf",
      "year": 2022
    },
    {
      "title": "Safety Data Sheet: HexForce Carbon Fabric (Hexcel, revision 1.1, as hosted by Revchem Composites)",
      "type": "sds",
      "url": "https://www.revchem.com/?p=30574",
      "year": 2020
    }
  ],
  "gaps": [
    "No flight, vacuum, radiation or low-Earth-orbit data for the IM7 fibre were found in the sources read.",
    "Electrical resistivity (printed as 1.5 x 10-3 ohm-cm in the IM7 datasheet) and the 6K weight, approximate yield and cross-sectional area rows are printed in exponent form or units that the checker cannot match, so they are left out.",
    "The HexPly 8552 laminate values in the IM7 datasheet and selector guide (0-degree tensile, flexural, compression and 90-degree tensile at 60% fibre volume) describe the prepreg system, not the fibre. They are not recorded here; see the im7-8552 profile.",
    "Hexcel's IM7 datasheet states that IM7-G 12K (0.25%) is qualified to NMS 818 (NCAMP). We did not confirm this in an NCAMP document. A search result (not opened) described a prepreg specification in which IM7 qualification to NMS 818 was still in progress; treat the qualification as unconfirmed until checked.",
    "The Hexcel datasheets do not name the manufacturing plant, so no producer country or production share is recorded. USGS Mineral Commodity Summaries do not cover PAN-based carbon fibre.",
    "No oxidation or thermal-ageing figure for the IM7 fibre in air was found. Wikipedia gives no numbers for carbon fibre oxidation.",
    "No fibre-only compression, interlaminar, fatigue or outgassing value for IM7 was found in the sources read.",
    "Thermal conductivity and coefficient of thermal expansion are printed without a stated direction (axial or transverse).",
    "No hazard data for the IM7 tow itself were found. The two SDSs read are for woven carbon fabric and a high-purity carbon thread, not for IM7 tow.",
    "PubChem hazard data for acrylonitrile, the monomer for PAN, could not be opened (automated access blocked), so precursor hazards are not recorded.",
    "Property names carbon_content, linear_density and filament_diameter are not in spores/property-canon.yaml and are kept as printed.",
    "Designations: only the trade name HexTow IM7 is recorded; no UNS, EN or AISI-style codes apply to a carbon fibre."
  ],
  "story": {
    "why": "Carbon fibre is a fine carbon filament used as reinforcement in composite parts. HexTow IM7 is Hexcel's intermediate-modulus carbon fibre, made from PAN and supplied as 12K tows. Hexcel's datasheet prints a typical tensile strength of 5670 MPa and a tensile modulus of 276 GPa for the fibre. Hexcel sells IM7 for weaving, prepregging, filament winding, braiding and pultrusion, so it is an input to composite parts rather than a finished part.",
    "uses": [
      {
        "where": "Aerospace structures",
        "line": "Hexcel says IM7-G 12K (0.25%) carbon fiber has been qualified to NMS 818 Carbon Fiber Specification (NCAMP). That lets a buyer call out an industry standard, aerospace grade fibre without writing its own specification. We did not confirm that qualification in an NCAMP document."
      },
      {
        "where": "Racing cars and boats",
        "line": "Hexcel's selector guide says its standard and intermediate modulus fibres are selected for Formula 1 cars, competition racing boats and high-performance cars."
      }
    ],
    "can_do": [
      {
        "label": "Strength",
        "line": "Carry a typical tensile strength of 5670 MPa at a density of 1.78 g/cm3, per Hexcel's IM7 datasheet.",
        "scope": "material"
      },
      {
        "label": "Give a stiffer fibre than AS4",
        "line": "a tensile modulus of 276 GPa against 231 GPa for AS4, per Hexcel's selector guide.",
        "scope": "material"
      },
      {
        "label": "Strength",
        "line": "Be woven, prepregged, filament wound, braided or pultruded, as Hexcel recommends for the fibre.",
        "scope": "material"
      }
    ],
    "compare": "Against Hexcel's standard-modulus AS4 fibre, IM7 has a typical tensile strength of 5670 MPa against 4501 MPa, and a tensile modulus of 276 GPa against 231 GPa (Hexcel selector guide). Against the newer IM8, the IM8 datasheet prints 6170 MPa and 304 GPa, so IM8 is stronger and stiffer. The IM6 datasheet prints 5860 MPa and 279 GPa, and the AS7 datasheet, which describes AS7 as high strain, prints 4930 MPa and 243 GPa. Hexcel calls its performance values representative, not guaranteed, and the figures come from separate datasheets rather than one test series.",
    "compare_rows": [
      {
        "label": "Tensile strength",
        "benchmark": "ultimate_tensile_strength",
        "scope": "material"
      },
      {
        "label": "Tensile modulus",
        "benchmark": "elastic_modulus",
        "scope": "material"
      },
      {
        "label": "Density",
        "benchmark": "density",
        "scope": "material"
      }
    ],
    "handling": [
      "Store indoors in the original container, below 35°C and below 50% relative humidity.",
      "Avoid creating dust. Wear goggles with side protection when handling cut or abraded fibre.",
      "Read the supplier's safety data sheet for your sizing before use."
    ],
    "good_for": [
      "Structures that need more stiffness and strength than a standard-modulus fibre: IM7 gives 276 GPa against 231 GPa for AS4.",
      "Aerospace programmes that specify a qualified fibre: Hexcel says IM7-G 12K (0.25%) is qualified to NMS 818, pending independent confirmation."
    ],
    "watch_out": [
      "Low strain at failure: IM7 breaks at 1.8% elongation according to Hexcel.",
      "Ageing: Hexcel's storage guidance gives one year for unsized fibre and five years for GP or GS sized fibre; beyond that the fibre may process badly.",
      "Typical values, not guarantees: Hexcel calls its performance figures representative."
    ],
    "verdict": "In Hexcel's range, IM7 is the stiffer and stronger choice over AS4, and Hexcel says it is qualified to NMS 818 for aerospace work. Confirm that qualification with NCAMP before you rely on it.",
    "recipe": {
      "line": "HexTow IM7 is a continuous, PAN-based carbon fibre. A polyacrylonitrile (PAN) precursor is heated to drive off non-carbon atoms, which leaves carbon fibre, and Hexcel then surface treats and sizes the yarn (Wikipedia; Hexcel datasheet).",
      "parts": [
        {
          "name": "Carbon",
          "symbol": "C",
          "role": "The fibre itself. Hexcel prints a carbon content of 95.0% for IM7; the sizing and other elements make up the balance, and the datasheet does not itemise them."
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "The Hexcel fabric SDS and the Rave thread SDS classify carbon fibre as not hazardous. Both describe dust, and the Hexcel SDS notes mild irritation.",
        "points": [
          {
            "label": "Dust",
            "line": "Fine dust clouds may form explosive mixtures with air, per the Hexcel fabric SDS. The Rave SDS advises avoiding dust."
          },
          {
            "label": "Skin and eyes",
            "line": "Hexcel's SDS notes mild, temporary mechanical irritation of the eyes and skin."
          },
          {
            "label": "Exposure limit",
            "line": "The Rave SDS gives an EU occupational exposure limit of 10 mg/m3 TWA for carbon (C) fibres."
          }
        ],
        "level": 0,
        "verdict": "Not classified as hazardous in the SDSs we checked"
      },
      {
        "title": "If a part fails",
        "lead": "Breakage at low strain is the main mechanical risk. The sources do not give a failure test for finished parts.",
        "points": [
          {
            "label": "Strain at failure",
            "line": "Hexcel gives IM7 an ultimate elongation at failure of 1.8%, so the fibre can break after only a small stretch."
          }
        ]
      },
      {
        "title": "Storage and handling",
        "points": [
          {
            "label": "Storage",
            "line": "Hexcel says to store it indoors, below 35°C and below 50% relative humidity."
          },
          {
            "label": "Age",
            "line": "Hexcel gives one year for unsized fibre and five years for GP or GS sized fibre."
          }
        ],
        "verdict": "Keep it indoors and in its original container"
      }
    ]
  },
  "updated": "2026-11-02",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 18,
    "unreachable": 2,
    "caveats": 3,
    "note": "Read by an AI assistant on 2026-11-02 from the Hexcel datasheets (IM7, IM8, AS7, IM6), the Hexcel selector guide, the Wikipedia article, and two SDSs. Hexcel's NMS 818 qualification claim is not confirmed in an NCAMP document. PubChem and the NCAMP base specification could not be opened."
  },
  "sources": {
    "hexcel-im7-datasheet": {
      "title": "HexTow IM7 Carbon Fiber Product Data Sheet (Hexcel Corporation, copyright 2023, CTA 351 AG23)",
      "id": "Hexcel CTA 351 AG23; the same file is also served at wp-content/uploads/2026/01/IM7_HexTow_DataSheet.pdf",
      "url": "https://www.hexcel.com/wp-content/uploads/2025/12/IM7_HexTow_DataSheet.pdf",
      "year": 2023,
      "kind": "datasheet",
      "license": "Hexcel data sheet, cited not reproduced"
    },
    "hexcel-selector-guide": {
      "title": "HexTow Carbon Fiber: aerospace-grade and industrial-grade selector guide with composite properties (Hexcel, CTU 396 FB25)",
      "id": "Hexcel CTU 396 FB25, copyright 2025",
      "url": "https://www.hexcel.com/wp-content/uploads/2026/01/HexTowSelectorGuide.pdf",
      "year": 2025,
      "kind": "datasheet",
      "license": "Hexcel brochure, cited not reproduced"
    },
    "hexcel-im8-datasheet": {
      "title": "HexTow IM8 Carbon Fiber Product Data Sheet (Hexcel Corporation)",
      "id": "Hexcel CTA IM8 product data sheet, copyright 2023",
      "url": "https://hexcel.com/wp-content/uploads/2026/01/IM8_HexTow_DataSheet.pdf",
      "year": 2023,
      "kind": "datasheet",
      "license": "Hexcel data sheet, cited not reproduced"
    },
    "hexcel-as7-datasheet": {
      "title": "HexTow AS7 Carbon Fiber Product Data Sheet (Hexcel Corporation)",
      "id": "Hexcel AS7 product data sheet (upload path 2025/12)",
      "url": "https://hexcel.com/wp-content/uploads/2025/12/AS7_Aerospace_HexTow_DataSheet.pdf",
      "year": 2025,
      "kind": "datasheet",
      "license": "Hexcel data sheet, cited not reproduced"
    },
    "hexcel-im6-datasheet": {
      "title": "HexTow IM6 Carbon Fiber Product Data Sheet (Hexcel Corporation)",
      "id": "Hexcel IM6 product data sheet (upload path 2025/12)",
      "url": "https://hexcel.com/wp-content/uploads/2025/12/IM6_HexTow_DataSheet.pdf",
      "year": 2025,
      "kind": "datasheet",
      "license": "Hexcel data sheet, cited not reproduced"
    },
    "wikipedia-carbon-fiber": {
      "title": "Carbon fiber (Wikipedia article): composition, precursors and history only",
      "id": "en.wikipedia.org Carbon_fiber",
      "url": "https://en.wikipedia.org/wiki/Carbon_fiber",
      "year": 2026,
      "kind": "web",
      "license": "CC BY-SA 4.0 (Wikipedia text, cited for precursor names only)"
    },
    "rave-sds": {
      "title": "Safety Data Sheet: High purity carbon fibers in carbon fiber threads (Rave Scientific, SDS00170CC1016 v4.0, 5 October 2022)",
      "id": "Rave Scientific SDS00170CC1016, version 4.0; EC # 231-955-3",
      "url": "https://ravescientific.com/images/pdf/SDS00170CC1016-01_Carbon_Fibre.pdf",
      "year": 2022,
      "kind": "datasheet",
      "license": "Supplier SDS, linked not reproduced"
    },
    "hexforce-sds": {
      "title": "Safety Data Sheet: HexForce Carbon Fabric, product 20584US-2 (Hexcel Corporation, revision 1.1, 8/10/2020), as hosted by Revchem Composites",
      "id": "Hexcel SDS, revision 1.1 supersedes 5/1/2015",
      "url": "https://www.revchem.com/?p=30574",
      "year": 2020,
      "kind": "datasheet",
      "license": "Supplier SDS, linked not reproduced"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/hextow-im7/"
}