When selecting materials for electrical insulation or structural support, epoxy fiberglass laminates are the industry standard. However, choosing between G10, G11, FR4, and FR5 can be challenging. While they share a similar substrate of alkali-free glass cloth and epoxy resin, their performance in high-temperature and flame-retardant environments varies significantly.
Core Similarities
Before diving into the differences, it is important to note that all four materials offer:
- Excellent Mechanical Strength: High durability for structural parts.
- Superior Insulation: Ideal for electrical components.
- Chemical Resistance: Highly resistant to weak acids, alkalis, and organic solvents.
Key Differences: Temperature & Flame Retardancy
The primary factors that distinguish these NEMA-grade materials are their thermal limits and UL ratings.
1.Temperature Resistance Grade
- G10 & FR4:These are standard-temperature materials. G10 withstands ~120°C, while FR4 is rated for ~130°C.
- G11 & FR5: These are high-temperature grades using modified epoxy resins, capable of continuous use at 150°C and short-term peaks up to 180°C.
2.Flame Retardancy (UL94 V0)
- FR4 and FR5: The "FR" stands for Flame Retardant. These materials contain bromine or halogen-free additives to meet the UL94 V0 standard.
- G10 and G11: These are non-flame retardant grades, typically used where fire safety is not the primary concern.
Technical Data Comparison Table
For a quick reference, here is the technical breakdown of G10, G11, FR4, and FR5 properties:
| Parameter | G10 | FR4 | G11 | FR5 |
| Continuous Temp | ≈120℃ | ≈130℃ | ≈150℃ | ≈150℃ |
| Flame Retardant | No (HB) | Yes (V0) | No (HB) | Yes (V0) |
| Bending Strength | ≥300 MPa | ≥340 MPa | ≥340 MPa | ≥340 MPa |
| Resin Type | Ordinary | Ordinary | Modified | Modified |
Which Material Should You Choose?
G10: The Economical Choice
Best for conventional mechanical parts and spacers where flame retardancy is not required.
FR4: The All-Rounder
The most widely used material, specifically PCB accessories and electrical partitions that require flame retardation.
G11: The High-Temp Professional
Ideal for high-temperature equipment brackets and motor gaskets that operate in extreme heat without flame-retardant needs.
FR5: The Premium High-Performance Grade
Designed for high-power electronic devices requiring both high-temperature stability (150°C) and UL94 V0 flame retardancy.
Detailed Technical Data Sheet
For engineers and technical buyers, the following table provides a detailed breakdown of the physical and electrical properties of RDS Composite epoxy laminates:
Click to View Full Technical Data Sheet (Detailed Specifications)
| Parameter | G10 | G11 | FR4 | FR5 |
|---|---|---|---|---|
| Continuous use temperature | ≈120℃ | ≈150℃ | ≈130℃ | ≈150℃ |
| Short term temperature peak | ≈150℃ | ≈180℃ | ≈150℃ | ≈180℃ |
| Flame retardant rating | Non-flame retardant (HB or V2) | Non-flame retardant (HB) | V0（UL94） | V0（UL94） |
| Density (g/cm³) | 1.75–1.90 | 1.80–1.95 | 1.70–1.90 | 1.80–1.95 |
| Bending strength (normal) | ≥300 MPa | ≥340 MPa | ≥340 MPa | ≥340 MPa |
| Insulation resistance after immersion | ≥5.0×10¹⁰ Ω | ≥5.0×10¹⁰ Ω | ≥5.0×10⁸ Ω | ≥5.0×10¹⁰ Ω |
| Electrical strength (oil at 90℃) | ≥14.2 kV/mm | ≥14.2 kV/mm | ≥14.2 kV/mm | ≥14.2 kV/mm |
| Dielectric constant (50 Hz) | ≤5.5 | ≤5.5 | ≤5.5 | ≤5.5 |
| Dielectric loss factor (50 Hz) | ≤0.04 | ≤0.04 | ≤0.04 | ≤0.04 |
| Water absorption (24h) | 0.1–0.6% | 0.1–0.2% | 0.1–0.2% | 0.1–0.2% |
| Thermal expansion coefficient (CTE) | ≈8.3–10.0×10⁻⁶/℃ | ≈5.5–6.6×10⁻⁶/℃ | ≈7.2–9.0×10⁻⁶/℃ | ≈5.5–6.6×10⁻⁶/℃ |
Reliable Quality from RDS Composite
At RDS Composite, we manufacture a wide range of epoxy fiberglass laminates meeting NEMA, DIN, and GOST standards. From raw material procurement to final production, we ensure our products meet international standards for reliability and performance.
Need a quote or technical advice? Contact our engineering team today for timely delivery and expert service.