G11 Material Guide

Overview

G11 is a high-temperature glass cloth reinforced epoxy laminate designed for applications requiring superior thermal resistance, electrical insulation, mechanical strength, and dimensional stability compared with standard G10 materials.

Manufactured by impregnating woven fiberglass cloth with high-performance epoxy resin and curing under heat and pressure, G11 retains its mechanical and electrical properties at significantly higher operating temperatures than G10. It is widely used in electrical, aerospace, industrial, and high-temperature engineering applications.

G11 is commonly regarded as the high-temperature version of G10 and is frequently specified where thermal reliability and insulation performance are critical.

G11 is widely used in:

  • Electrical Insulation Systems
  • High-Temperature Electrical Equipment
  • Aerospace Components
  • Industrial Machinery
  • Transformers
  • Switchgear Systems
  • Semiconductor Equipment
  • Precision Engineering Components

Due to its exceptional thermal and electrical performance, G11 is one of the most widely used high-temperature fiberglass laminate materials.


Material Specification

PropertyValue
Material DesignationG11
Full NameHigh Temperature Glass Cloth Epoxy Laminate
Material FamilyThermoset Composite Laminate
Reinforcement MaterialWoven Glass Fiber
Resin SystemHigh Temperature Epoxy Resin
Density1.80–2.00 g/cm³
AppearanceGreen, Yellow, Natural
Standard FormsSheet, Plate, Rod, Tube

Material Composition

G11 consists of fiberglass reinforcement and high-performance epoxy resin.

ComponentFunction
Glass Fiber FabricStructural Reinforcement
High Temperature Epoxy ResinThermal Stability
Curing AgentsCrosslinking
AdditivesProperty Enhancement

The specialized resin system allows G11 to maintain performance at elevated temperatures.


Common G11 Grades

GradeCharacteristics
Standard G11High Temperature Electrical Applications
Natural G11Unpigmented Laminate
Electrical Grade G11High Voltage Insulation
Precision Machining Grade G11Tight Tolerance Components
High Thermal G11Elevated Temperature Service

Mechanical Properties

Typical Values

PropertyValue
Tensile Strength280–380 MPa
Flexural Strength400–600 MPa
Compressive Strength450–650 MPa
Elastic Modulus18–25 GPa
Impact ResistanceExcellent

Mechanical Performance

PropertyPerformance
StrengthExcellent
StiffnessExcellent
Wear ResistanceGood
Dimensional StabilityOutstanding

G11 maintains mechanical strength at temperatures where many engineering materials begin to degrade.


Physical Properties

PropertyValue
Density1.80–2.00 g/cm³
Water Absorption<0.15%
Surface HardnessHigh
Moisture ResistanceExcellent
Dimensional StabilityOutstanding

The tightly bonded fiberglass-epoxy structure provides excellent environmental stability.


Thermal Properties

PropertyValue
Continuous Service Temperature180°C
Short-Term Temperature ResistanceUp to 220°C
Glass Transition Temperature (Tg)170–200°C
Thermal Conductivity0.25–0.35 W/m·K
Thermal ExpansionLow

G11 offers significantly higher temperature capability than G10.


Thermal Performance Comparison

MaterialContinuous Service Temperature
G10130–140°C
FR4130–140°C
G11180°C
High Tg FR4170–180°C

G11 is specifically designed for demanding thermal environments.


Strength-to-Weight Ratio

MaterialDensity (g/cm³)Tensile Strength
G111.90350 MPa
G101.90300 MPa
Aluminum 60612.70310 MPa
FR41.85300 MPa

G11 provides excellent structural performance while remaining lightweight.


Electrical Properties

Typical Values

PropertyValue
Dielectric Strength18–30 kV/mm
Dielectric Constant4.5–5.2
Volume Resistivity>10¹⁴ Ω·cm
Surface Resistivity>10¹³ Ω
Arc ResistanceExcellent

Electrical Performance

PropertyPerformance
Electrical InsulationOutstanding
High Voltage ResistanceOutstanding
Thermal Electrical StabilityOutstanding
Industrial Electrical ApplicationsOutstanding

G11 is frequently used in high-voltage and high-temperature electrical insulation systems.


Moisture Resistance

PropertyPerformance
Water AbsorptionVery Low
Humidity ResistanceExcellent
Environmental StabilityExcellent
Outdoor DurabilityGood

The material maintains insulation properties even in humid environments.


Chemical Resistance

Chemical EnvironmentPerformance
WaterExcellent
Oils & GreasesExcellent
Transformer OilsExcellent
FuelsGood
Mild AcidsGood
Mild AlkalisGood

G11 performs well in industrial and electrical operating environments.


Wear & Machining Performance

PropertyPerformance
CNC MachiningExcellent
DrillingExcellent
MillingExcellent
Precision TolerancesExcellent

G11 is suitable for manufacturing precision insulation and structural components.


Manufacturing Characteristics

Manufacturing ProcessRating
CNC MachiningOutstanding
Waterjet CuttingExcellent
GrindingExcellent
DrillingExcellent
Precision FabricationOutstanding

Proper tooling and dust extraction are recommended when machining fiberglass laminates.


International Standards

StandardEquivalent
NEMA LI-1G11
ASTM D709Applicable
UL RecognitionAvailable
RoHSCompliant
REACHCompliant

Available Forms

Product TypeAvailability
G11 SheetYes
G11 PlateYes
G11 RodYes
G11 TubeYes
Machined ComponentsYes

Typical Applications

Electrical Industry

  • High Voltage Insulators
  • Transformer Components
  • Bus Bar Supports
  • Switchgear Insulation

Industrial Equipment

  • Structural Insulators
  • Wear Components
  • Precision Fixtures
  • High Temperature Machinery Parts

Aerospace Industry

  • Electrical Insulation Systems
  • Lightweight Structural Components
  • Thermal Isolation Parts

Semiconductor Industry

  • Equipment Insulators
  • Process Chamber Components
  • Precision Electrical Supports

Power Generation

  • Generator Insulation
  • Motor Insulation Systems
  • Electrical Distribution Equipment

Transportation Industry

  • Rail Electrical Systems
  • EV Insulation Components
  • High Voltage Assemblies

Advantages

High Temperature Resistance

Provides superior thermal performance compared with G10.

Outstanding Electrical Insulation

Suitable for high-voltage and high-temperature applications.

Excellent Mechanical Strength

Maintains structural integrity under load.

Low Moisture Absorption

Ensures stable performance in humid environments.

Excellent Dimensional Stability

Supports precision engineering applications.

Easy Machining

Can be fabricated into complex custom components.


Limitations

Higher Cost Than G10

Premium thermal performance increases material cost.

Not Suitable for Extreme Temperatures

Cannot match ceramic or polyimide materials at very high temperatures.

Brittle Under Severe Impact

Fiberglass laminates can chip under excessive shock loading.

Dust Generation During Machining

Requires proper machining safety procedures.


Comparison with Engineering Laminates

PropertyG11G10FR4High Tg FR4
Temperature ResistanceOutstandingGoodGoodExcellent
Electrical InsulationOutstandingOutstandingOutstandingOutstanding
Mechanical StrengthExcellentExcellentExcellentExcellent
Moisture ResistanceExcellentExcellentExcellentExcellent
CostHigherLowerLowerModerate

Comparison with G10

PropertyG11G10
Continuous TemperatureHigher
Thermal StabilityBetter
Electrical Performance at High TemperatureBetter
CostHigher
Industrial ReliabilityBetter

G11 is generally selected when operating temperatures exceed the practical limits of G10.


Available Surface Finishes

Standard Finishes

  • Natural Finish
  • Green Finish
  • Matte Finish

Functional Finishes

  • Precision Ground Surface
  • Electrical Grade Surface
  • High Temperature Industrial Surface

Specialty Configurations

  • G11 Sheet
  • G11 Plate
  • G11 Rod
  • High Temperature G11
  • Electrical Grade G11

Frequently Asked Questions (FAQ)

What is G11?

G11 is a high-temperature fiberglass-reinforced epoxy laminate designed for electrical insulation and structural applications.

What is G11 used for?

Typical applications include:

  • Electrical Insulators
  • Transformers
  • Switchgear
  • Aerospace Components
  • Industrial Equipment

Is G11 stronger than G10?

Mechanical properties are similar, but G11 maintains performance much better at elevated temperatures.

Is G11 electrically insulating?

Yes. G11 provides excellent dielectric strength and electrical insulation properties.

What temperature can G11 withstand?

G11 typically supports continuous operating temperatures up to approximately 180°C.

Why choose G11?

Because it combines:

  • High Temperature Resistance
  • Excellent Electrical Insulation
  • Strong Mechanical Properties
  • Moisture Resistance
  • Dimensional Stability

What is the difference between G11 and G10?

G11 uses a higher-performance epoxy system that provides significantly better thermal resistance than standard G10.

Does GCNOV provide G11 machining services?

Yes. GCNOV provides:

  • G11 Component Manufacturing
  • CNC Machining Services
  • Electrical Insulation Parts
  • High Temperature Structural Components
  • Prototype Development
  • Low-Volume Production
  • Mass Production