NEMA G-10 glass epoxy laminate (non-flame-retardant woven glass/epoxy) G-10

spore: profile
id: g-10-glass-epoxy-laminate
spore_version: 0.2
family: glass-and-composites
name: NEMA G-10 glass epoxy laminate (non-flame-retardant woven glass/epoxy)
abbreviation: G-10
role: Rigid laminate of woven fibreglass cloth bonded with epoxy resin, non-flame-retardant grade
category: composites
type: glass-fiber-reinforced
summary: |
  NEMA G-10 is a non-flame-retardant laminate of woven fibreglass sheet bonded with epoxy resin. The Gund Company datasheet gives a typical density of 1.850 g/cc for G-10 and says the sheet keeps its mechanical, electrical and physical properties up to 130 °C. Polymershapes lists a temperature index of 140 °C for its Acculam Epoxyglas G10 non FR sheet. In a conductive anodic filament (CAF) substrate ranking that Turbini quotes, G-10 resists CAF better than FR-4 but worse than CEM-3, cyanate ester and BT.
best_for: Structural and electrical insulating parts up to 130 °C where a non-flame-retardant grade is acceptable, per the Gund datasheet
weakest_at: Flame rating (class HB in the Gund datasheet) and CAF resistance in humid high-voltage circuits, below CEM-3, cyanate ester and BT in Turbini's ranking
identity:
  formula: Woven fibreglass sheet in a cured epoxy resin binder; a laminate with no single formula (the Gund SDS describes it as cured epoxy with glass fibre and mineral fillers, composition proprietary)
  source: gund-g10
  where: Product description paragraph and Standards line (NEMA LI-1 Grade G-10)
  designations:
    - system: MIL
      code: I-24768/2
      note: GEE type, as printed
      source: gund-g10
      where: Standards line
    - system: Trade name
      code: Epoxyglas G10
      note: Acculam Epoxyglas G10 non FR, Polymershapes product line
      source: polymershapes-g10
      where: Title block
tags:
  environments: []
  stresses: []
  applications:
    - structures
    - electronics-and-chips
properties:
  - benchmark: density
    label: Density, typical value, G-10 (Gund)
    value: 1.85
    unit: g/cc
    scope: material
    conditions:
      basis: typical value in the TYPICAL VALUES column for G-10; the datasheet says the data are typical, not specification values
    method: Typical value printed on the datasheet, printed as 0.067 (1.850) lbs/in3 (g/cc); no test method is printed for this row
    status: ground
    source: gund-g10
    where: Properties table, PHYSICAL group, Density row, G-10 column
  - benchmark: moisture_absorption
    label: Moisture absorption, 3 mm specimen, G-10 (Gund)
    value: 0.13
    unit: '%'
    scope: material
    conditions:
      specimen: 3 mm
      method_as_printed: ASTM D570
    method: Typical value in the G-10 column; the NEMA requirement column is not used here
    status: ground
    source: gund-g10
    where: Properties table, PHYSICAL group, Moisture Absorption (3 mm) row
  - benchmark: flexural_strength
    label: Flexural strength, lengthwise, 3 mm, G-10 (Gund)
    value: 435
    unit: MPa
    scope: material
    conditions:
      direction: lengthwise
      specimen: 3 mm
      method_as_printed: ASTM D790
      form: laminate sheet, G-10 grade
    method: Typical value in the G-10 column, printed as 63 (435) ksi (MPa)
    status: ground
    source: gund-g10
    where: Properties table, MECHANICAL group, Flexural Strength Lengthwise (3 mm) row
  - benchmark: flexural_strength
    label: Flexural strength, crosswise, 3 mm, G-10 (Gund)
    value: 373
    unit: MPa
    scope: material
    conditions:
      direction: crosswise
      specimen: 3 mm
      method_as_printed: ASTM D790
      form: laminate sheet, G-10 grade
    method: Typical value in the G-10 column, printed as 54 (373) ksi (MPa)
    status: ground
    source: gund-g10
    where: Properties table, MECHANICAL group, Flexural Strength Crosswise (3 mm) row
  - benchmark: flexural_strength
    label: Flexural strength, ISO 178, G-10 (Gund)
    value: 483
    unit: MPa
    scope: material
    conditions:
      method_as_printed: ISO 178
      direction: not printed
      form: laminate sheet, G-10 grade
    method: Typical value in the G-10 column
    status: ground
    source: gund-g10
    where: Properties table, MECHANICAL group, Flexural Strength (ISO 178) row
  - benchmark: dielectric_strength
    label: Dielectric strength, perpendicular, G-10 (Gund)
    value: 485
    unit: V/mil
    scope: material
    conditions:
      direction: perpendicular
      method_as_printed: ASTM D149
    method: Typical value in the G-10 column
    status: ground
    source: gund-g10
    where: 'Properties table, ELECTRICAL group, Dielectric Strength: Perpendicular row'
  - benchmark: dielectric_strength
    label: Electric strength, perpendicular, 90 °C in oil, 1.5 mm, G-10 (Gund)
    value: 15
    unit: kV/mm
    scope: material
    conditions:
      temperature: 90 °C in oil
      thickness: 1.5 mm
      method_as_printed: IEC 60243-1
    method: Typical value in the G-10 column, the IEC 60243-1 row
    status: ground
    source: gund-g10
    where: 'Properties table, ELECTRICAL group, Electric Strength: Perpendicular at 90°C in Oil (1.5 mm) row'
  - benchmark: dielectric_constant
    label: Permittivity, condition A, 1 MHz, 3 mm, G-10 (Gund)
    value: 4.8
    unit: '-'
    scope: material
    conditions:
      condition: A
      frequency: 1 MHz
      specimen: 3 mm
      method_as_printed: ASTM D150
    method: Typical value in the G-10 column
    status: ground
    source: gund-g10
    where: Properties table, ELECTRICAL group, Permittivity Condition A at 1 MHz (3 mm) row
  - benchmark: dielectric_constant
    label: Permittivity, condition D-24/23, 1 MHz, 3 mm, G-10 (Gund)
    value: 4.7
    unit: '-'
    scope: material
    conditions:
      condition: D-24/23
      frequency: 1 MHz
      specimen: 3 mm
      method_as_printed: ASTM D150
    method: Typical value in the G-10 column
    status: ground
    source: gund-g10
    where: Properties table, ELECTRICAL group, Permittivity Condition D-24/23 at 1 MHz (3 mm) row
  - benchmark: dissipation_factor
    label: Dissipation factor, condition A, 1 MHz, 3 mm, G-10 (Gund)
    value: 0.016
    unit: '-'
    scope: material
    conditions:
      condition: A
      frequency: 1 MHz
      specimen: 3 mm
      method_as_printed: ASTM D150
    method: Typical value in the G-10 column
    status: ground
    source: gund-g10
    where: Properties table, ELECTRICAL group, Dissipation Factor Condition A at 1 MHz (3 mm) row
  - benchmark: dissipation_factor
    label: Dissipation factor, condition D-24/23, 1 MHz, 3 mm, G-10 (Gund)
    value: 0.019
    unit: '-'
    scope: material
    conditions:
      condition: D-24/23
      frequency: 1 MHz
      specimen: 3 mm
      method_as_printed: ASTM D150
    method: Typical value in the G-10 column
    status: ground
    source: gund-g10
    where: Properties table, ELECTRICAL group, Dissipation Factor Condition D-24/23 at 1 MHz (3 mm) row
  - benchmark: max_service_temp
    label: Temperature up to which properties are maintained, G-10 (Gund)
    value: 130
    unit: °C
    scope: material
    conditions:
      basis: stated in the product description as the temperature up to which mechanical, electrical and physical properties are maintained
    method: Statement in the product description paragraph; the datasheet gives no separate test for this figure
    status: ground
    source: gund-g10
    where: Product description paragraph (first page)
  - benchmark: flexural_strength
    label: Flexural strength, lengthwise, 0.125 in, condition A, Acculam Epoxyglas G10 non FR (Polymershapes)
    value: 448
    bound: lower
    unit: MPa
    scope: material
    conditions:
      direction: lengthwise
      thickness: 0.125 in
      condition: A
      note_as_printed: printed as greater than 65,000 psi
    method: Typical value printed on the Polymershapes sheet, printed as greater than 65,000 psi (448 MPa)
    status: ground
    source: polymershapes-g10
    where: Typical Properties table, Physical Data, Flexural Strength-LW-A-.125 row
  - benchmark: flexural_strength
    label: Flexural strength, crosswise, 0.125 in, condition A, Acculam Epoxyglas G10 non FR (Polymershapes)
    value: 345
    bound: lower
    unit: MPa
    scope: material
    conditions:
      direction: crosswise
      thickness: 0.125 in
      condition: A
      note_as_printed: printed as greater than 50,000 psi
    method: Typical value printed on the Polymershapes sheet, printed as greater than 50,000 psi (345 MPa)
    status: ground
    source: polymershapes-g10
    where: Typical Properties table, Physical Data, Flexural Strength-CW-A-.125 row
  - benchmark: dielectric_constant
    label: Permittivity, condition A, Acculam Epoxyglas G10 non FR (Polymershapes)
    value: 4.8
    unit: '-'
    scope: material
    conditions:
      condition: A
      frequency: not printed on the sheet
    method: Typical value printed on the Polymershapes sheet; the test frequency is not printed
    status: ground
    source: polymershapes-g10
    where: Typical Properties table, Electrical Data, Permittivity-A row
  - benchmark: dissipation_factor
    label: Dissipation factor, condition A, Acculam Epoxyglas G10 non FR (Polymershapes)
    value: 0.017
    unit: '-'
    scope: material
    conditions:
      condition: A
      frequency: not printed on the sheet
    method: Typical value printed on the Polymershapes sheet; the test frequency is not printed
    status: ground
    source: polymershapes-g10
    where: Typical Properties table, Electrical Data, Dissipation Factor-A row
  - benchmark: temperature_index
    label: Temperature index, Acculam Epoxyglas G10 non FR (Polymershapes)
    value: 140
    unit: °C
    scope: material
    conditions:
      basis: printed as Temperature Index, 140 °C (284 °F); the sheet does not name the test or the endpoint
    method: Value printed in the Physical Data section of the Polymershapes sheet
    status: ground
    note: Non-canonical property name; the sheet's own label is kept. Polymershapes' figure is a different number from the Gund 130 °C statement and is shown side by side, not merged.
    source: polymershapes-g10
    where: Typical Properties table, Physical Data, Temperature Index row
  - benchmark: decomposition_temperature
    label: Temperature above which combustion products form, per the Gund SDS
    value: 300
    unit: °C
    scope: material
    conditions:
      basis: 'SDS statement: temperatures above this value produce products of combustion'
    method: Statement in the SDS, not a measured decomposition temperature; printed as 572 °F (300 °C)
    status: ground
    source: gund-sds
    where: Section 10, Conditions to avoid (polymerization) row
corrosion:
  - environment: High humidity with a DC voltage gradient (conductive anodic filament, CAF)
    headline: Moisture and voltage can grow a copper salt filament through the glass-epoxy interface of G-10, and in Turbini's ranking G-10 is less resistant than CEM-3, cyanate ester and BT.
    effect: Turbini describes CAF as a copper salt that grows from anode to cathode along the epoxy-glass interface, enhanced by high humidity, high voltage gradient and higher processing temperatures. Turbini gives a susceptibility trend drawn from earlier substrate comparisons, which places G-10 after FR-4 and polyimide (more resistant than those) and before CEM-3, cyanate ester (CE) and BT (less resistant than those), with BT the most resistant and MC-2 the least. The source gives this as a ranking only, with no G-10 humidity test numbers.
    rating: moderate
    conditions:
      basis: qualitative ranking from a historical review that quotes earlier substrate studies; no G-10 test conditions printed
    source: turbini-caf
    where: Section 'CAF Resistant Materials' (substrate comparison and ranking)
  - environment: Humid air (moisture uptake of the laminate)
    headline: The typical moisture absorption of G-10 is 0.13 % after the ASTM D570 test, which Turbini links to CAF behaviour across substrates.
    effect: Low moisture uptake is the reason Turbini gives for BT being the most CAF-resistant material in his comparison. G-10 is not tested for humidity ageing in the source; the 0.13 % figure is a single typical value for a 3 mm specimen.
    rating: low
    conditions:
      specimen: 3 mm
      method_as_printed: ASTM D570
    source: gund-g10
    where: Properties table, Moisture Absorption (3 mm) row; compare with Turbini, CAF Resistant Materials
  - environment: Heat above 300 °C, fire or thermal decomposition
    headline: Above 300 °C, G-10 gives off irritating and toxic gases, which the Gund SDS lists as hydrogen bromide, carbon monoxide and carbon dioxide.
    effect: The Gund SDS lists hydrogen bromide among the decomposition gases. The Gund datasheet states that G-10 is non-brominated, so the two Gund documents disagree on halogen content; the supplier should confirm the composition of the sheet being bought before use in a halogen-sensitive application.
    rating: moderate
    conditions:
      temperature: above 300 °C
    source: gund-sds
    where: Section 5 (Hazardous decomposition products) and Section 10 (Conditions to avoid)
risks:
  hazards:
    - text: The Gund SDS states that G-10 has no hazards as shipped; hazards arise only after machining, punching or thermal decomposition.
      ghs: []
      source: gund-sds
      where: Section 2, Hazard statements
    - text: For dust from machining the SDS gives skin sensitisation, skin irritation, respiratory sensitisation and eye sensitisation (category 2B) hazards.
      ghs:
        - H316
        - H317
        - H334
      source: gund-sds
      where: Section 2, GHS classification and hazard statements
    - text: The SDS lists an exposure guideline for fibrous glass dust in Section 8 and recommends local exhaust ventilation to control dust.
      ghs: []
      source: gund-sds
      where: Section 8, Exposure Guidelines and Ventilation
  failure_risks:
    - mode: Conductive anodic filament shorts between closely spaced conductors
      trigger: High humidity with a DC voltage gradient across the laminate; higher processing temperatures add to the risk (Turbini)
      consequence: A copper salt filament grows along the epoxy-glass interface from anode to cathode and can create a short circuit.
      severity: high
      source: turbini-caf
      where: Abstract and Introduction
    - mode: Sensitisation from machining dust
      trigger: Cutting, drilling, punching or grinding that generates dust
      consequence: Skin and respiratory sensitisation (H317 and H334 in the SDS).
      severity: moderate
      source: gund-sds
      where: Section 2, hazard statements
    - mode: Decomposition gases during overheating
      trigger: Temperatures above 300 °C, in a fire or in thermal decomposition
      consequence: Hydrogen bromide, carbon monoxide and carbon dioxide may be released, per the SDS.
      severity: moderate
      source: gund-sds
      where: Section 5 and Section 10
  side_effects:
    - text: The SDS says ingredients may cause moderate eye, skin and throat irritation, and that machining dust may irritate the eyes.
      affects: Operators and workshop air during cutting and drilling
      source: gund-sds
      where: Section 11, Toxicological information; Section 8, Eye Protection
  handling:
    - text: Use local exhaust ventilation to control dust, and an approved dust respirator if dust exposure exceeds the guidelines (SDS Section 8).
      source: gund-sds
      where: Section 8, Ventilation and Respiratory Protection
    - text: Wear safety glasses with side shields and protective gloves where dust may contact the skin (SDS Section 8).
      source: gund-sds
      where: Section 8, Eye and Skin Protection
    - text: The SDS lists no special handling and storage precautions for the cured sheet (Section 7).
      source: gund-sds
      where: Section 7, Handling and Storage
  mitigations:
    - text: Keep the service temperature at or below 130 °C, the temperature up to which the Gund datasheet says properties are maintained.
      source: gund-g10
      where: Product description paragraph
    - text: For humid, high-voltage circuitry, Turbini's ranking puts BT the most CAF-resistant; the source notes a cost penalty for BT.
      source: turbini-caf
      where: CAF Resistant Materials, final paragraph
uses:
  - application: electronics-and-chips
    device: Electrical insulation and printed circuit boards
    example: The Gund datasheet says NEMA G-10 is used in electrical insulation, printed circuit boards and structural components, and that it is non-brominated and non-flame-retardant.
    source: gund-g10
    where: Product description paragraph
  - application: structures
    device: Structural components, including cryogenic applications
    example: Polymershapes says its Acculam Epoxyglas G10 non FR sheet suits many structural and cryogenic applications where halogenated compounds may be undesirable.
    source: polymershapes-g10
    where: Typical Applications paragraph
supply:
  - subject: Borates (boron minerals used in specialty glass and ceramics)
    producers:
      - country: Turkey
        year: 2025
      - country: Bolivia
        year: 2025
      - country: Chile
        year: 2025
      - country: China
        year: 2025
      - country: Peru
        year: 2025
      - country: Argentina
        year: 2025
      - country: Russia
        year: 2025
      - country: Germany
        year: 2025
    recycling: 'USGS boron chapter: recycling is insignificant.'
    substitutes:
      - 'USGS boron chapter: substitution is possible in detergents, enamels, insulation and soaps; some enamels can use phosphates as the glass-producing substance.'
    source: usgs-mcs2026-boron
    where: 'World Production and Reserves table, All forms, 2025 column (thousand metric tons): Turkey refined borates 1,500; Bolivia ulexite 380; Chile ulexite 300; China boric oxide equivalent 230; Peru crude borates 220; Argentina crude ore 170; Russia datolite ore 80; Germany compounds 40. The United States is withheld (W) and the world total is printed as XX, so no country share is calculated. Glass link: Domestic Production and Use paragraph (glass and ceramics were the leading domestic users in 2025) and World Resources paragraph (colemanite, primarily used in heat-resistant glass). The chapter does not say that E-glass contains boron.'
documents:
  - title: NEMA G-10 Glass Epoxy Laminate technical data sheet (The Gund Company, TGCR 10/2025)
    type: datasheet
    url: https://thegundcompany.com/wp-content/uploads/2024/03/NEMA-G-10-Glass-Epoxy-Laminate-by-The-Gund-Co.pdf
    year: 2025
  - title: Acculam Epoxyglas G10 non FR product data sheet (Polymershapes)
    type: datasheet
    url: https://www.polymershapes.com/wp-content/uploads/2020/04/Polymershapes_Accurate_DataSheet-Acculam-Epoxyglas-G10-NonFR.pdf
    year: 2020
  - title: Safety Data Sheet, G-10 and related glass epoxy laminates (The Gund Company, revision 08/01/2024)
    type: sds
    url: https://thegundcompany.com/wp-content/uploads/2025/02/Glass-Epoxy-Laminates-SDS-by-The-Gund-Co.pdf
    year: 2024
  - title: 'Conductive Anodic Filament (CAF) Formation: An Historic Perspective (Turbini, 2005)'
    type: paper
    url: https://www.electronics.org/system/files/technical_resource/E17&S02-3.pdf
    year: 2005
  - title: 'Mineral Commodity Summaries 2026: Boron (U.S. Geological Survey)'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-boron.pdf
    year: 2026
gaps:
  - Supply of the woven E-glass cloth and of the epoxy resin (producers, country shares, critical-mineral lists) was not found in any source read in this run. The supply section covers only borates from the USGS boron chapter, which names glass as a use but does not name G-10 or E-glass.
  - The Norplex-Micarta G-10 page says the NEMA LI-1 standard has no minimum glass transition temperature requirement. No glass transition value for the laminate was read.
  - Thermal expansion, thermal conductivity and glass transition temperature are not recorded. The Gund datasheet has a THERMAL heading, but its values did not come through in the PDF text layer and were not read.
  - 'The Ryertex Grade G10 technical data bulletin (W.S. Hampshire) was read but not used for values: it states that the product contains bromine and is rated V-0, so it is not the non-flame-retardant G-10 grade.'
  - The Gund SDS lists hydrogen bromide among decomposition products, while the Gund datasheet says G-10 is non-brominated. This is recorded as a conflict and not resolved.
  - No space flight, vacuum outgassing or radiation data for G-10 were found in this run. The spacecraft support use cited in the lane brief is not sourced in this profile.
  - No cryogenic (77 K or 4 K) mechanical data for the non-flame-retardant G-10 grade were found. The G-10CR cryogenic grade is a different product and its values are not used here.
  - Gund rows for Izod impact, arc resistance, comparative tracking index, breakdown voltage and Rockwell hardness were not recorded, because their names are not in the canonical property list or the values are given as bounds.
  - The Polymershapes temperature index (140 °C) uses a non-canonical property name, temperature_index, and its test basis is not printed.
  - The Polymershapes permittivity and dissipation factor rows do not print a test frequency.
  - Humidity ageing or CAF test numbers for G-10 itself were not found; Turbini gives a qualitative ranking only.
  - Process (how the laminate is impregnated and pressed) is not described in the sources read.
  - Hazard data rest on one Gund SDS that covers G-10 with other laminate grades. No CAS number or PubChem record for the cured laminate was found.
license: CC-BY-4.0
updated: '2026-11-01'
review:
  status: draft
  method: assistant
  checked_values: 18
  unreachable: 0
  caveats: 3
  note: Read by an AI assistant on 2026-11-01 from two G-10 datasheets (Gund, Polymershapes), one Gund SDS, one CAF paper (Turbini) and the Wikipedia FR-4 article for history. The Ryertex bulletin was read but not used because it describes a brominated V-0 product.
story:
  recipe:
    line: NEMA G-10 is a laminate of continuous-filament woven fibreglass sheet bonded with cured epoxy resin. The Norplex-Micarta G-10 page describes the cloth as plain-weave E-glass with a non-brominated epoxy resin system. The Gund SDS describes the cured product as epoxy with glass fibre and mineral fillers and does not give a percentage split.
    parts:
      - name: Woven glass fibre fabric
        share: not disclosed (proprietary)
        role: Continuous-filament woven fibreglass sheet that carries the mechanical load in the laminate.
      - name: Epoxy resin binder
        share: not disclosed (proprietary)
        role: Cured resin that bonds the glass layers and carries the electrical insulation.
      - name: Mineral fillers
        share: not disclosed (proprietary)
        role: Named in the Gund SDS as part of the cured product; the datasheet does not list them.
  risk_groups:
    - title: For people
      level: 0
      verdict: Not hazardous as shipped; dust is the hazard
      lead: The Gund SDS says the sheet has no hazards as shipped. The hazards come from dust and heat, from machining and from overheating.
      points:
        - label: The sheet
          line: The SDS states that no hazards are associated with the product as shipped. Hazards arise only after machining, punching or thermal decomposition.
        - label: Dust
          line: Cutting, drilling or grinding produces dust that can cause skin and respiratory sensitisation (H317 and H334 in the SDS). Local exhaust ventilation and gloves are advised.
        - label: Heat
          line: Above 300 °C the SDS lists hydrogen bromide, carbon monoxide and carbon dioxide among the products of combustion.
    - title: If the laminate is used in humid, high-voltage circuits
      verdict: CAF is the failure to design against
      lead: The main electrical risk is not heat or dust. It is copper salt filament growth in humid conditions with voltage across the laminate.
      points:
        - label: CAF ranking
          line: Turbini's susceptibility trend places G-10 more resistant than FR-4 and polyimide, but less resistant than CEM-3, cyanate ester and BT, and BT is the most resistant.
        - label: Moisture
          line: The typical moisture absorption of G-10 is 0.13 % (ASTM D570, 3 mm specimen) per the Gund datasheet.
    - title: Handling and storage
      points:
        - label: Storage
          line: The SDS calls for no special handling or storage precautions for the cured sheet.
        - label: Dust control
          line: Use local exhaust ventilation and, where dust exposure exceeds guidelines, an approved dust respirator.
  why: NEMA G-10 is a non-flame-retardant glass epoxy laminate, made from woven fibreglass sheet bonded with epoxy resin (Gund datasheet). Wikipedia's FR-4 article calls G-10 the predecessor of FR-4, which adds flame retardance. G-10 is chosen where a rigid, electrically insulating laminate is needed up to 130 °C and a non-flame-retardant grade is acceptable. Polymershapes describes its G10 non FR sheet as having a halogen-free epoxy binder, which suits applications where halogenated compounds are undesirable, and says the sheet keeps high mechanical strength and electrical insulating qualities under both dry and humid conditions.
  uses:
    - where: Electrical insulation and printed circuit boards
      line: The Gund Company says NEMA G-10 is used in electrical insulation, printed circuit boards and structural components for demanding environments.
    - where: Structural and cryogenic applications
      line: Polymershapes says its Acculam Epoxyglas G10 non FR sheet is used in many structural and cryogenic applications where halogenated compounds may be undesirable.
  can_do:
    - label: Structural load
      benchmark: flexural_strength
      value: 435 MPa lengthwise, 373 MPa crosswise
      line: The Gund typical flexural strength is 435 MPa lengthwise and 373 MPa crosswise on 3 mm specimens (ASTM D790).
    - label: Electrical insulation
      benchmark: dielectric_constant
      value: 4.8 at 1 MHz
      line: The Gund typical permittivity is 4.8 and the dissipation factor is 0.016 at 1 MHz in condition A (ASTM D150).
    - label: Dielectric strength
      benchmark: dielectric_strength
      value: 485 V/mil
      line: The Gund typical dielectric strength perpendicular to the laminate is 485 V/mil (ASTM D149).
    - label: Service temperature
      benchmark: max_service_temp
      value: 130 °C
      line: The Gund product description says the laminate keeps its mechanical, electrical and physical properties up to 130 °C.
  compare: G-10 is the non-flame-retardant predecessor grade of FR-4 (Wikipedia), and it lacks the self-extinguishing behaviour that FR-4 has. Gund rates G-10 HB in its flammability row. In the CAF ranking Turbini gives, G-10 resists filament growth better than FR-4 but worse than CEM-3, cyanate ester and BT. The typical G-10 density is 1.850 g/cc and its typical flexural strength lengthwise is 435 MPa, both per the Gund datasheet, and the compare rows below set these against other laminate grades on the same benchmarks.
  compare_rows:
    - label: Density
      benchmark: density
    - label: Flexural strength, lengthwise
      benchmark: flexural_strength
    - label: Maximum service temperature
      benchmark: max_service_temp
  handling:
    - Use local exhaust ventilation to control dust when cutting, drilling or grinding the sheet.
    - Wear safety glasses with side shields and gloves where dust may reach the skin.
    - Keep the service temperature at or below 130 °C, the temperature to which properties are maintained.
    - Do not heat the sheet above 300 °C, where combustion products are released.
  good_for:
    - Rigid electrical insulation and structural parts, where the Gund datasheet lists electrical insulation, printed circuit boards and structural components as uses.
    - Structural and cryogenic applications where halogenated compounds are undesirable, per the Polymershapes sheet.
  watch_out:
    - 'Flame rating: G-10 is rated HB in the Gund datasheet, so it does not self-extinguish like FR-4.'
    - 'Humid high-voltage circuits: in Turbini''s ranking G-10 is less resistant to conductive anodic filament than CEM-3, cyanate ester and BT.'
    - 'Halogen content: the Gund datasheet says non-brominated, but the Gund SDS lists hydrogen bromide among decomposition products.'
    - 'Dust: machining produces dust that can sensitise the skin and airways.'
  verdict: A useful rigid insulator up to 130 °C where a non-flame-retardant grade is acceptable. For humid, high-voltage circuitry, Turbini's CAF ranking points to CEM-3, cyanate ester or BT instead.
sources:
  gund-g10:
    title: NEMA G-10 Glass Epoxy Laminate technical data sheet (The Gund Company, TGCR 10/2025)
    id: The Gund Company, TGCR 10/2025
    url: https://thegundcompany.com/wp-content/uploads/2024/03/NEMA-G-10-Glass-Epoxy-Laminate-by-The-Gund-Co.pdf
    year: 2025
    kind: datasheet
    license: manufacturer data sheet, cited not reproduced
  polymershapes-g10:
    title: Acculam Epoxyglas G10 non FR Product Data Sheet (Polymershapes)
    id: undated; file uploaded 2020/04 per the URL
    url: https://www.polymershapes.com/wp-content/uploads/2020/04/Polymershapes_Accurate_DataSheet-Acculam-Epoxyglas-G10-NonFR.pdf
    year: 2020
    kind: datasheet
    license: supplier data sheet, cited not reproduced
  gund-sds:
    title: 'Safety Data Sheet: G-10, G-11/G-11H, G-11R, G-13, G-15 Glass Epoxy Laminate (The Gund Company)'
    id: Version 1, revision date 08/01/2024
    url: https://thegundcompany.com/wp-content/uploads/2025/02/Glass-Epoxy-Laminates-SDS-by-The-Gund-Co.pdf
    year: 2024
    kind: datasheet
    license: supplier SDS, cited not reproduced
  turbini-caf:
    title: 'Conductive Anodic Filament (CAF) Formation: An Historic Perspective (Turbini, ECWC 10 and APEX 2005)'
    id: Laura J. Turbini, University of Toronto; presented at ECWC 10, IPC Printed Circuits Expo and APEX 2005
    url: https://www.electronics.org/system/files/technical_resource/E17&S02-3.pdf
    year: 2005
    kind: paper
    license: conference paper, cited not reproduced
  wiki-fr4:
    title: FR-4 (Wikipedia article)
    id: Wikipedia, English edition
    url: https://en.wikipedia.org/wiki/FR-4
    year: 2026
    kind: web
    license: Wikipedia text, cited for composition and history only
  usgs-mcs2026-boron:
    title: 'Mineral Commodity Summaries 2026: Boron (U.S. Geological Survey)'
    id: USGS Mineral Commodity Summaries 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-boron.pdf
    year: 2026
    kind: report
    license: US government work, cited not reproduced
  norplex-g10-what-is:
    title: 'What is G-10: Glass Epoxy? (Norplex-Micarta)'
    id: undated manufacturer web page
    url: https://www.norplex-micarta.com/structural-materials/what-is-g-10/
    kind: web
    license: manufacturer web page, cited not reproduced
  norplex-nema-li1:
    title: NEMA LI 1 electrical industry standards page (Norplex-Micarta)
    id: undated manufacturer web page
    url: https://www.norplex-micarta.com/electrical-materials/electrical-industry-standards/nema/
    kind: standard
    license: manufacturer web page, cited not reproduced