IG-110 isotropic graphite IG-110

spore: profile
id: ig-110-isotropic-graphite
spore_version: 0.2
family: carbon-materials
name: IG-110 isotropic graphite
abbreviation: IG-110
role: isostatically pressed nuclear graphite grade (Toyo Tanso), studied by ORNL for a high-temperature gas-cooled reactor
category: carbon
type: graphite
summary: |
  IG-110 is a fine-grained, isostatically pressed graphite made by Toyo Tanso and qualified by Oak Ridge National Laboratory (ORNL) as a candidate material for a high-temperature gas-cooled reactor. ORNL measured a bulk density of 1.77 g/cm3 before irradiation, per its 2018 summary report. Neutron irradiation sharply lowered thermal conductivity: one specimen irradiated at a measured 256 degC read 2.80 W/m/K at 25 degC, against 129 W/m/K before irradiation in the axial direction.
best_for: Reference nuclear graphite where ORNL baseline and irradiation data for the grade matter, such as reactor-core qualification studies
weakest_at: 'Irradiation and air oxidation: thermal conductivity falls sharply after neutron irradiation, and the graphite oxidizes in air at high temperature'
identity:
  formula: C (carbon; synthetic graphite made from petroleum-based carbon materials)
  designations:
    - system: Trade name
      code: IG-110
      source: ornl-tm2018-1040
      where: Section 2.1 (Grade IG-110, Toyo Tanso Co., Ltd.)
  source: ornl-tm2022-1839
  where: Table 1 (manufacturer Toyo Tanso, LTD; coke type Petroleum; forming method Isostatically pressed)
tags:
  environments: []
  stresses:
    - extreme-heat
  applications:
    - structures
    - electronics-and-chips
properties:
  - benchmark: density
    label: Bulk density, pre-irradiation specimens
    value: 1.77
    unit: g/cm3
    scope: material
    conditions:
      form: isostatically pressed IG-110, as received
      specimens: all specimen shapes
      reported_as: average plus or minus 1 sigma
    method: Measured by ORNL on pre-irradiation specimens and printed in the report table
    uncertainty: ± 0.017 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), Density (g/cm3), all specimens
  - benchmark: density
    label: Bulk density, ORNL 2022 Table 1
    value: 1.761
    unit: g/cm3
    scope: material
    conditions:
      basis: bulk density by mensuration, IG-110 column
      grade_column: Isotropic
    method: Measured at ORNL and printed in Table 1 of the 2022 review
    status: ground
    note: The 2018 ORNL report gives 1.77 and this 2022 table gives 1.761; both values are printed by ORNL and both are kept here.
    source: ornl-tm2022-1839
    where: Table 1, row Bulk density (mensuration)
  - benchmark: elastic_modulus
    label: Dynamic Young's modulus, MB specimens, axial
    value: 9.1
    unit: GPa
    scope: material
    conditions:
      specimen_shape: MB, as printed
      orientation: AX (axial, with gravity during pressing)
      temperature: not printed in Table 2.2
    method: Dynamic Young's modulus measured by ORNL on pre-irradiation specimens
    uncertainty: ± 0.23 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), Dynamic Young's Modulus (GPa), MB, AX
  - benchmark: elastic_modulus
    label: Dynamic Young's modulus, MB specimens, transverse
    value: 9.7
    unit: GPa
    scope: material
    conditions:
      specimen_shape: MB, as printed
      orientation: TR (transverse)
      temperature: not printed in Table 2.2
    method: Dynamic Young's modulus measured by ORNL on pre-irradiation specimens
    uncertainty: ± 0.22 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), Dynamic Young's Modulus (GPa), MB, TR
  - benchmark: compressive_strength
    label: Compression strength, CRS specimens, axial
    value: 77
    unit: MPa
    scope: material
    conditions:
      specimen_shape: CRS, as printed
      orientation: AX (axial)
      temperature: not printed in Table 2.2
    method: Compression test by ORNL on pre-irradiation specimens
    uncertainty: ± 3.3 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), Compression Strength (MPa), CRS, AX
  - benchmark: compressive_strength
    label: Compression strength, CRS specimens, transverse
    value: 77
    unit: MPa
    scope: material
    conditions:
      specimen_shape: CRS, as printed
      orientation: TR (transverse)
      temperature: not printed in Table 2.2
    method: Compression test by ORNL on pre-irradiation specimens
    uncertainty: ± 2.1 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), Compression Strength (MPa), CRS, TR
  - benchmark: flexural_strength
    label: 4-point flexural strength, MB specimens, axial
    value: 34
    unit: MPa
    scope: material
    conditions:
      test: 4-point flexural
      specimen_shape: MB, as printed
      orientation: AX (axial)
    method: 4-point flexural test by ORNL on a small subset of pre-irradiation specimens
    uncertainty: ± 1.8 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), 4-point Flexural Strength (MPa), MB, AX
  - benchmark: flexural_strength
    label: 4-point flexural strength, MB specimens, transverse
    value: 36
    unit: MPa
    scope: material
    conditions:
      test: 4-point flexural
      specimen_shape: MB, as printed
      orientation: TR (transverse)
    method: 4-point flexural test by ORNL on a small subset of pre-irradiation specimens
    uncertainty: ± 1.3 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), 4-point Flexural Strength (MPa), MB, TR
  - benchmark: cte
    label: Mean coefficient of thermal expansion at 500 °C, MB axial
    value: 4.5
    unit: ppm/K
    scope: material
    conditions:
      temperature: mean CTE at 500 °C, as printed
      specimen_shape: MB, as printed
      orientation: AX (axial)
    method: Mean CTE measured by ORNL; the source prints the unit as 10-6 K-1, and the number is unchanged in ppm/K
    uncertainty: ± 0.04 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), Mean CTE at 500°C (10-6 K-1), MB, AX
  - benchmark: cte
    label: Mean coefficient of thermal expansion at 500 °C, MB transverse
    value: 4.2
    unit: ppm/K
    scope: material
    conditions:
      temperature: mean CTE at 500 °C, as printed
      specimen_shape: MB, as printed
      orientation: TR (transverse)
    method: Mean CTE measured by ORNL; the source prints the unit as 10-6 K-1, and the number is unchanged in ppm/K
    uncertainty: ± 0.11 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), Mean CTE at 500°C (10-6 K-1), MB, TR
  - benchmark: isotropy_ratio
    label: Isotropy ratio of thermal expansion
    value: 1.057
    unit: '-'
    scope: material
    conditions:
      basis: ratio as printed in Table 2.2, pre-irradiation specimens
    method: Ratio printed by ORNL in the same table as the CTE rows
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), Isotropy Ratio
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 25 °C, TD4 specimens, axial
    value: 129
    unit: W/m/K
    scope: material
    conditions:
      temperature: 25 °C, as printed
      specimen_shape: TD4, as printed
      orientation: AX (axial)
    method: Thermal conductivity measured by ORNL on a few pre-irradiation specimens
    uncertainty: ± 7.2 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), Thermal Conductivity at 25°C (W/m/K), TD4, AX
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 25 °C, TD4 specimens, transverse
    value: 130
    unit: W/m/K
    scope: material
    conditions:
      temperature: 25 °C, as printed
      specimen_shape: TD4, as printed
      orientation: TR (transverse)
    method: Thermal conductivity measured by ORNL on a few pre-irradiation specimens
    uncertainty: ± 3.7 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), Thermal Conductivity at 25°C (W/m/K), TD4, TR
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 500 °C, TD4 specimens, axial
    value: 73
    unit: W/m/K
    scope: material
    conditions:
      temperature: 500 °C, as printed
      specimen_shape: TD4, as printed
      orientation: AX (axial)
    method: Thermal conductivity measured by ORNL on a few pre-irradiation specimens
    uncertainty: ± 3.5 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), Thermal Conductivity at 500°C (W/m/K), TD4, AX
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 500 °C, TD4 specimens, transverse
    value: 77
    unit: W/m/K
    scope: material
    conditions:
      temperature: 500 °C, as printed
      specimen_shape: TD4, as printed
      orientation: TR (transverse)
    method: Thermal conductivity measured by ORNL on a few pre-irradiation specimens
    uncertainty: ± 1.4 (1σ)
    status: ground
    source: ornl-tm2018-1040
    where: Table 2.2 (page 3), Thermal Conductivity at 500°C (W/m/K), TD4, TR
  - benchmark: grain_size
    label: Average grain size
    value: 20
    unit: µm
    scope: material
    conditions:
      basis: average grain size, IG-110 column, as printed
    method: Printed by ORNL as an average value in the general properties table
    status: ground
    source: ornl-tm2022-1839
    where: Table 1, row Grain size (µm), IG-110 column
  - benchmark: ash_content
    label: Ash content
    value: 10
    bound: upper
    unit: ppm
    scope: material
    conditions:
      basis: printed as less than 10 ppm
    method: Printed by ORNL in the general properties table
    status: ground
    source: ornl-tm2022-1839
    where: Table 1, row Ash content (ppm), IG-110 column
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, ORNL 2022 Table 1
    value: 14.9
    unit: MPa
    scope: material
    conditions:
      basis: IG-110 column of the general properties table; test method not printed
    method: Printed by ORNL in the general properties table; the table does not name the test
    status: ground
    note: The test method is not printed. This is a different test from the 34 MPa flexural value in the 2018 report, so the two are not directly comparable.
    source: ornl-tm2022-1839
    where: Table 1, row Tensile strength (MPa), IG-110 column
  - benchmark: compressive_strength
    label: Compressive strength, ORNL 2022 Table 1
    value: 73.44
    unit: MPa
    scope: material
    conditions:
      basis: IG-110 column of the general properties table; test method not printed
    method: Printed by ORNL in the general properties table; the table does not name the test
    status: ground
    note: The test method is not printed. The 2018 report gives 77 MPa for axial compression specimens (Table 2.2), so the two sources are shown side by side.
    source: ornl-tm2022-1839
    where: Table 1, row Compressive strength (MPa), IG-110 column
  - benchmark: elastic_modulus
    label: Dynamic Young's modulus, ORNL 2022 Table 1
    value: 8.767
    unit: GPa
    scope: material
    conditions:
      basis: IG-110 column of the general properties table
    method: Printed by ORNL in the general properties table
    status: ground
    note: This 2022 value differs from the 9.1 GPa axial and 9.7 GPa transverse values in the 2018 report; both are kept.
    source: ornl-tm2022-1839
    where: Table 1, row Dynamic young's modulus (GPa), IG-110 column
  - benchmark: poissons_ratio
    label: Poisson's ratio
    value: 0.157
    unit: '-'
    scope: material
    conditions:
      basis: IG-110 column of the general properties table
    method: Printed by ORNL in the general properties table
    status: ground
    source: ornl-tm2022-1839
    where: Table 1, row Poisson ratio, IG-110 column
  - benchmark: oxidation_activation_energy
    label: Activation energy for air oxidation, Smith data set
    value: 195
    unit: kJ/mol
    scope: material
    conditions:
      atmosphere: air (21% O2)
      temperature_range: 536 to 695 °C
      flow_rate: 10 L/min
      specimen: cylinder, 2.54 D x 5.08 H cm
    method: Arrhenius fit of oxidation rate data for IG-110 in air, as tabulated by ORNL
    status: ground
    note: The same table gives 187 kJ/mol for the Fuller data set and 169 kJ/mol for the Chi data set, measured over other temperature ranges.
    source: ornl-tm2022-1839
    where: Table 3 (Selected kinetic parameters oxidation of IG-110 by air), Smith row
  - benchmark: oxidation_activation_energy
    label: Activation energy for air oxidation, Fuller data set
    value: 187
    unit: kJ/mol
    scope: material
    conditions:
      atmosphere: air (21% O2)
      temperature_range: 450 to 750 °C
      flow_rate: 0.5 L/min
      specimen: cylinder, 0.84 D x 1.90 H cm
    method: Arrhenius fit of oxidation rate data for IG-110 in air, as tabulated by ORNL
    status: ground
    source: ornl-tm2022-1839
    where: Table 3 (Selected kinetic parameters oxidation of IG-110 by air), Fuller row
  - benchmark: oxidation_activation_energy
    label: Activation energy for air oxidation, Chi data set
    value: 169
    unit: kJ/mol
    scope: material
    conditions:
      atmosphere: air (21% O2)
      temperature_range: 603 to 808 °C
      flow_rate: 10 L/min
      specimen: cylinder, 2.54 D x 2.54 H cm
    method: Arrhenius fit of oxidation rate data for IG-110 in air, as tabulated by ORNL
    status: ground
    source: ornl-tm2022-1839
    where: Table 3 (Selected kinetic parameters oxidation of IG-110 by air), Chi row
  - benchmark: thermal_conductivity
    label: Thermal conductivity after neutron irradiation, sample T11T15
    value: 2.8
    unit: W/m/K
    scope: material
    conditions:
      state: after neutron irradiation
      specimen: TD3, TR orientation
      design_temperature: 300 °C
      measured_temperature: 256 °C
      test_temperature: 25 °C
      fluence: printed in the source with an exponent, not reproduced here
    method: Post-irradiation thermal conductivity at 25 °C measured by ORNL on one specimen of the irradiation set
    status: ground
    note: One row of the appendix table; irradiated values in that table are far below the 129 W/m/K unirradiated axial value.
    source: ornl-tm2018-1040
    where: Appendix B.5.1 (Room Temperature), row T11T15
  - benchmark: volume_change
    label: Volume change after neutron irradiation, sample T10T06
    value: -7.39
    unit: '%'
    scope: material
    conditions:
      state: after neutron irradiation
      specimen: MB, TR orientation
      design_temperature: 300 °C
      measured_temperature: 410 °C
      fluence: printed in the source with an exponent, not reproduced here
    method: Post-irradiation volume change (delta V over V0) measured by ORNL
    status: ground
    source: ornl-tm2018-1040
    where: Appendix B.1 (Post-irradiation dimension and Young's modulus), row T10T06
corrosion:
  - environment: Air at high temperature (dry air, oxidation in the kinetic regime)
    headline: In air, IG-110 oxidizes, and the rate rises steeply with temperature.
    effect: ORNL's 2022 review tabulates apparent activation energies for IG-110 oxidation in air of 195 kJ/mol (Smith data set) and 187 kJ/mol (Fuller data set). The review says the kinetic regime lies 'approximately between' the quoted range for specimens of the standard shape, provided oxidant supply is ample.
    rating: moderate
    conditions:
      temperature: 536 to 695 °C in the Smith data set
      atmosphere: air
    source: ornl-tm2022-1839
    where: Table 3 and Section 4.3.5 (Conclusions on Acute Oxidation Tests)
  - environment: Metal impurities in the graphite
    headline: Metal impurities can speed oxidation in an uncontrolled way.
    effect: ORNL's review states that metal impurities that may act as oxidation catalysts may accelerate oxidation rates in an uncontrollable way.
    rating: moderate
    conditions:
      basis: general statement in the conclusions, not a measured IG-110 value
    source: ornl-tm2022-1839
    where: Section 4.3.5 (Conclusions on Acute Oxidation Tests), last bullet
risks:
  hazards:
    - text: 'PubChem''s Carbon record says: ''This chemical does not meet GHS hazard criteria for 40.2% (1095 of 2727) of reports.'' No graphite-specific safety data sheet for IG-110 was found in this run.'
      ghs: []
      source: pubchem-carbon
      where: GHS Classification section of the Carbon record (CID 5462310)
    - text: The Carbon record lists eye-irritation and respiratory-irritation codes for some company notifications only. It is an element entry, not a record for IG-110.
      ghs:
        - H319
        - H335
      source: pubchem-carbon
      where: GHS Classification section, Hazard Statements list
  failure_risks:
    - mode: Oxidation of hot graphite in air
      trigger: Air at high temperature; the Smith data set covers 536 to 695 °C
      consequence: Oxidation rises steeply with temperature (activation energy 195 kJ/mol in the Smith data set). The review reports property changes after oxidation to 'nominally 2.5% and 7.5% weight loss' from older Japanese data, shown in figures only.
      severity: high
      source: ornl-tm2022-1839
      where: Table 3 and Section 5.3 (Degradation of oxidized graphite IG-110 properties)
    - mode: Thermal conductivity loss under neutron irradiation
      trigger: Neutron irradiation at a 300 °C design temperature
      consequence: Thermal conductivity at 25 °C falls to 2.80 W/m/K in the sampled specimen, against 129 W/m/K axially before irradiation.
      severity: high
      source: ornl-tm2018-1040
      where: Appendix B.5.1 and Table 2.2
    - mode: Dimensional change under neutron irradiation
      trigger: Neutron irradiation at a 300 °C design temperature and 410 °C measured temperature
      consequence: Volume changes by -7.39% in sample T10T06 (MB, TR). ORNL reports that length change differs between the two orientations, which it calls unexpected for near-isotropic graphite.
      severity: moderate
      source: ornl-tm2018-1040
      where: Appendix B.1 and Section 4 conclusions
  side_effects:
    - text: Irradiation changes the dimensions and the thermal properties of the same graphite, so a part can change shape and lose conduction at the same time (ORNL reports both).
      affects: Core graphite in a reactor, where heat must still leave the graphite
      source: ornl-tm2018-1040
      where: Section 4 conclusions and Appendix B
  handling:
    - text: PubChem's Carbon record gives precautionary statement codes for handling, but the wording of those codes is not printed in the record fetched in this run.
      source: pubchem-carbon
      where: Safety and Hazards, Precautionary Statements
    - text: ORNL measured the oxidation of IG-110 in air at high temperature, so hot graphite should be kept away from air where the process allows.
      source: ornl-tm2022-1839
      where: Section 4.3.2 (Graphite IG-110)
  mitigations:
    - text: ORNL states it is "imperative" to examine property changes in both distinct directions after irradiation, because length change differed between them.
      source: ornl-tm2018-1040
      where: Section 4 conclusions
uses:
  - application: structures
    device: Core graphite structures in a high-temperature gas-cooled reactor (candidate material, not a deployed use)
    example: ORNL and Toyo Tanso ran a joint program to qualify IG-110 as a candidate material for use in the Generation-IV high temperature gas-cooled nuclear reactor.
    source: ornl-tm2017-705
    where: Section 1 (Introduction)
  - application: electronics-and-chips
    device: Semiconductor manufacturing parts made from isotropic graphite (the industry is named; IG-110 is not named)
    example: Toyo Tanso names the semiconductor industry, where innovation is rapidly advancing, as a user of its isotropic graphite.
    source: toyo-tanso-special
    where: Industries section of the special graphite page
supply:
  - subject: Graphite, natural (USGS covers natural graphite; IG-110 is a synthetic grade)
    abundance: World resources exceed 800 million tons of recoverable graphite outside the United States (USGS, World Resources).
    producers:
      - country: China
        share_percent: 82
        year: 2025
      - country: Madagascar
        share_percent: 4.4
        year: 2025
      - country: Tanzania
        share_percent: 4.2
        year: 2025
    critical_lists:
      - list: EU critical raw materials, Fifth list 2023 (Natural Graphite is listed; the Commission page does not mark it strategic)
        listed: true
    recycling: 'USGS: ''The abundance of graphite in the world market inhibits increased recycling efforts.'''
    substitutes:
      - 'USGS: synthetic graphite powder, scrap from machined shapes and calcined petroleum coke compete for iron and steel uses; synthetic graphite powder and secondary synthetic graphite from machined shapes compete for battery uses.'
    source: usgs-mcs2026-graphite
    where: World Mine Production and Reserves table, 2025e (world total 1,800,000 t, rounded); China share from the text (estimated 82% of total world production); Madagascar and Tanzania shares calculated by Space Mushroom from 80,000 t and 75,000 t against the 1,800,000 t total. EU list status from the European Commission page (source key ec-crm).
media: []
documents:
  - title: 'ORNL/TM-2018/1040: Summary Report on Effects of Irradiation on Material IG-110 (prepared for Toyo Tanso Co., Ltd.)'
    type: report
    url: https://info.ornl.gov/sites/publications/Files/Pub118793.pdf
    year: 2018
  - title: 'ORNL/TM-2017/705: Report on Effects of Irradiation on Material IG-110'
    type: report
    url: https://info.ornl.gov/sites/publications/Files/Pub104952.pdf
    year: 2017
  - title: 'ORNL/TM-2022/1839: Oxidation Behavior and Property Degradation of Nuclear Graphites'
    type: report
    url: https://info.ornl.gov/sites/publications/Files/Pub172937.pdf
    year: 2022
  - title: 'PubChem compound record: Carbon (CID 5462310), GHS classification'
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/compound/5462310
    year: 2026
  - title: 'USGS Mineral Commodity Summaries 2026: Graphite (Natural)'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-graphite.pdf
    year: 2026
  - title: Toyo Tanso special graphite property data page (lists IG-11, not IG-110)
    type: datasheet
    url: https://www.toyotanso.com/Products/Special_graphite/data.html
gaps:
  - No IG-110 safety data sheet was found. The hazard entries use PubChem's Carbon record (CID 5462310), an element entry, not a graphite-specific record.
  - The Toyo Tanso property data page lists IG-11 but not IG-110, so no manufacturer datasheet value for IG-110 is used.
  - Irradiation values are recorded for one thermal conductivity row and one volume change row only. Fluence is printed with an exponent in the source and is left out. Irradiated strength, modulus, CTE and creep values are not recorded.
  - Oxidation rate constants (pre-exponential factors) are printed with exponents, so they are left out. Oxidized strength and fracture-toughness changes (ORNL 2022 Section 5.3) are shown in figures only.
  - 'Density differs between ORNL sources: 1.77 g/cm3 (2018 report) and 1.761 g/cm3 (2022 review). Both are kept; the difference is not resolved.'
  - The 2022 review's tensile and compressive values do not name the test method. The porosity column layout in the extracted text is unclear, so no porosity value is recorded.
  - Thermal conductivity and CTE at temperatures other than 25 and 500 °C were not found for IG-110 in these sources.
  - Supply data cover natural graphite only (USGS). No production-country data for synthetic isostatically pressed graphite such as IG-110 was found.
  - USGS 2025 critical minerals list status for graphite was not verified in this run. The EU list status is recorded.
  - Carbon atomic weight and atom counts were not read; the recipe gives components, not a formula ratio.
  - No space flight, vacuum or space-radiation data were found. The irradiation data are reactor tests (HFIR at ORNL).
  - 'Non-canonical property names used: grain_size, ash_content, compressive_strength, volume_change, isotropy_ratio, oxidation_activation_energy.'
license: CC-BY-4.0
updated: '2026-11-02'
review:
  status: draft
  method: assistant
  checked_values: 26
  unreachable: 0
  caveats: 2
  note: 'Values re-read by an AI assistant on 2026-11-02 from the ORNL PDFs (text extracted with pdftotext) and the USGS graphite summary. Two values carry caveats: the 2022 density and tensile test method.'
story:
  recipe:
    line: IG-110 is a synthetic graphite made from petroleum-based carbon materials and formed by isostatic pressing. ORNL describes nuclear graphite as a composite of filler, binder and pores, and says the vendor's process details are proprietary.
    parts:
      - name: Carbon filler
        symbol: C
        role: Carbon particles from a petroleum-based coke that form most of the graphite skeleton
        source: ornl-tm2022-1839
        where: Section 3 (Structure and properties) and Table 1, coke type Petroleum
      - name: Binder carbon
        role: Carbon that binds the filler together after forming, baking and graphitization
        source: ornl-tm2022-1839
        where: Section 3 (filler, binder and pores; manufacturing sequence)
      - name: Pores
        role: Open and closed voids that set the density and strength of the finished block
        source: ornl-tm2022-1839
        where: Section 3 and Table 2 (pore volumes)
  why: IG-110 is an isotropic nuclear graphite made by Toyo Tanso. Isotropic means its properties are nearly the same in every direction. ORNL and Toyo Tanso ran a joint program to qualify it for a Generation-IV high temperature gas-cooled reactor. The program measured its baseline properties and how neutron irradiation changes them, and the results are published in ORNL reports.
  uses:
    - where: Reactor core candidate
      line: ORNL and Toyo Tanso qualified IG-110 as a candidate material for a Generation-IV high temperature gas-cooled reactor. The sources we hold describe this as a qualification role, not a deployed use.
    - where: Semiconductor industry
      line: Toyo Tanso names the semiconductor industry as a user of its isotropic graphite. Its page does not name IG-110 in that list, so this is an industry-level claim.
  can_do:
    - label: Density
      benchmark: density
      line: ORNL measured a bulk density of 1.77 g/cm3 before irradiation, so one cubic centimetre of the graphite weighs about 1.77 grams.
    - label: Grain size
      benchmark: grain_size
      line: The average grain size is 20 µm, printed in ORNL's 2022 review. This is the finest of the three nuclear graphites that review compares.
    - label: Strength
      benchmark: flexural_strength
      line: Flexural strength is 34 MPa in the axial direction and 36 MPa in the transverse direction, before irradiation, in ORNL's 2018 report.
    - label: Heat conduction
      benchmark: thermal_conductivity
      line: Thermal conductivity at 25 °C is 129 W/m/K in the axial direction before irradiation. After irradiation, one specimen read 2.80 W/m/K.
    - label: Oxidation in air
      benchmark: oxidation_activation_energy
      line: Air oxidation has an activation energy of 195 kJ/mol in one data set and 187 kJ/mol in another, both printed in ORNL's 2022 review.
  compare: Among the three nuclear graphites that ORNL compares in its 2022 review, IG-110 has by far the finest average grain. PCEA is extruded and NBG-18 is vibrationally molded, while IG-110 is isostatically pressed. The forming method and the fine grain are the two features that separate IG-110 from the other two grades in that review.
  compare_rows:
    - label: Bulk density
      benchmark: density
    - label: Thermal conductivity at 25 °C
      benchmark: thermal_conductivity
    - label: Air oxidation activation energy
      benchmark: oxidation_activation_energy
  handling:
    - Keep hot graphite away from air where the process allows. ORNL measured oxidation of IG-110 in air at high temperature.
    - The hazard data are thin. The nearest record, PubChem's Carbon entry, lists eye and respiratory irritation codes for some company notifications, so control dust.
  good_for:
    - Reference data. ORNL measured baseline values for IG-110 in two reports and one 2022 review.
    - Reactor-core qualification work, where irradiation data for this grade already exist.
    - 'Parts that need similar strength in both directions: the flexural strength is 34 MPa axially and 36 MPa transversely.'
  watch_out:
    - Thermal conductivity falls sharply after irradiation. One specimen dropped from 129 W/m/K to 2.80 W/m/K.
    - Hot IG-110 oxidizes in air. The 2022 review reports activation energies of 195 kJ/mol and 187 kJ/mol.
    - 'Density differs between ORNL sources: 1.77 g/cm3 in the 2018 report and 1.761 g/cm3 in the 2022 review.'
  verdict: IG-110 is a well-documented nuclear graphite with ORNL baseline and irradiation data. Its weak points are irradiation-driven conductivity loss and oxidation in air at high temperature.
  risk_groups:
    - title: For people
      level: 1
      verdict: No IG-110 hazard data found; nearest is carbon
      lead: No safety data sheet for IG-110 itself was found. The nearest record is PubChem's Carbon entry.
      points:
        - label: Dust
          line: Most company notifications in the Carbon record do not meet GHS hazard criteria. Where codes appear, they are eye irritation and respiratory irritation.
    - title: If it is heated in air
      level: 2
      verdict: Oxidizes in air when hot
      lead: These results come from laboratory oxidation tests, not from incidents.
      points:
        - label: Air oxidation
          line: Air oxidation of IG-110 has activation energies of 195 kJ/mol and 187 kJ/mol in two data sets. ORNL's review shows oxidation rates rising steeply with temperature.
    - title: In a reactor
      level: 3
      verdict: Irradiation cuts thermal conductivity sharply
      lead: Irradiation changes the material. ORNL's data show a large drop in conductivity and a measurable volume change.
      points:
        - label: Thermal conductivity
          line: After irradiation, one specimen read 2.80 W/m/K at 25 °C, against 129 W/m/K before irradiation in the axial direction.
        - label: Shape
          line: In another specimen the volume changed by -7.39% after irradiation.
sources:
  ornl-tm2018-1040:
    title: Summary Report on Effects of Irradiation on Material IG-110 (ORNL/TM-2018/1040)
    id: ORNL/TM-2018/1040
    url: https://info.ornl.gov/sites/publications/Files/Pub118793.pdf
    year: 2018
    kind: report
    license: Approved for public release; distribution is unlimited (ORNL)
  ornl-tm2017-705:
    title: Report on Effects of Irradiation on Material IG-110 (ORNL/TM-2017/705)
    id: ORNL/TM-2017/705
    url: https://info.ornl.gov/sites/publications/Files/Pub104952.pdf
    year: 2017
    kind: report
    license: Approved for public release; distribution is unlimited (ORNL)
  ornl-tm2022-1839:
    title: Oxidation Behavior and Property Degradation of Nuclear Graphites (ORNL/TM-2022/1839)
    id: ORNL/TM-2022/1839 (Contescu and Paul, March 2022)
    url: https://info.ornl.gov/sites/publications/Files/Pub172937.pdf
    year: 2022
    kind: report
    license: Approved for public release; distribution is unlimited (ORNL)
  toyo-tanso-special:
    title: Toyo Tanso special graphite (isotropic graphite applications)
    url: https://www.toyotanso.com/Products/Special_graphite/
    kind: web
    license: Manufacturer web page, linked not reproduced
  toyo-tanso-data:
    title: Toyo Tanso special graphite property data (lists IG-11, not IG-110)
    url: https://www.toyotanso.com/Products/Special_graphite/data.html
    kind: datasheet
    license: Manufacturer web page, linked not reproduced
  usgs-mcs2026-graphite:
    title: 'Mineral Commodity Summaries 2026: Graphite (Natural)'
    id: USGS MCS 2026, February 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-graphite.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  pubchem-carbon:
    title: 'PubChem compound record: Carbon (CID 5462310), GHS classification'
    id: CID 5462310
    url: https://pubchem.ncbi.nlm.nih.gov/compound/5462310
    year: 2026
    kind: database
    license: public domain (NCBI)
  ec-crm:
    title: Critical raw materials (European Commission, Fifth list 2023 of critical raw materials for the EU)
    url: https://single-market-economy.ec.europa.eu/sectors/raw-materials/areas-specific-interest/critical-raw-materials_en
    year: 2023
    kind: web
    license: European Commission web page