Mica Fire Barrier Sheet – Standard
Mica Fire Barrier Sheet – Standard is a rigid mica sheet composed of approximately 90% Cogebi Muscovite or Phlogopite mica impregnated with a proprietary high-temperature-resistant silicone resin, supplied in five grades (505.2, 505.3, 505.4, 505.2P, 505.3P) in thicknesses from 0.1 to 1.5 mm. Muscovite grades (505.2, 505.3, 505.4) are rated for continuous service at 500°C and intermittent service to 800°C, while Phlogopite grades (505.2P, 505.3P) are rated for continuous service at 700°C and intermittent service to 1000°C, with dielectric strength greater than 25 kV/mm across the series. The series is UL-94V-O certified (E67143 M) and conforms to IEC 371-3-3 for high-temperature electrical insulation applications.
Key Properties
- Mica Content: ca. 90% (all grades) — IEC 371-2
- Thickness: 0.1–1.5 mm (all grades) — IEC 371-2
- Density: 2.15 (505.2, 505.3, 505.2P, 505.3P); 2.25 (505.4) — IEC 371-2
- Heat Resistance, Continuous Service: 500°C (505.2, 505.3, 505.4); 700°C (505.2P, 505.3P)
- Heat Resistance, Intermittent Service: 800°C (505.2, 505.3, 505.4); 1000°C (505.2P, 505.3P)
- Edge Strength: >1.3 kg/0.1mm (505.2, 505.3); >1.6 kg/0.1mm (505.4); >1 kg/0.1mm (505.2P, 505.3P) — in house
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- Specifications
- Applications
- General Info
- FAQs
Physical Properties
| Property | Value | Test Method |
| Mica Content | ca. 90% (all grades) | IEC 371-2 |
| Bond Content | ca. 10% (all grades) | IEC 371-2 |
| Thickness | 0.1–1.5 mm (all grades) | IEC 371-2 |
| Density | 2.15 (505.2, 505.3, 505.2P, 505.3P); 2.25 (505.4) | IEC 371-2 |
| Water Absorption | <1% (all grades) | ISO 62 |
Mechanical Properties
| Property | Value | Test Method |
| Edge Strength | >1.3 kg/0.1mm (505.2, 505.3); >1.6 kg/0.1mm (505.4); >1 kg/0.1mm (505.2P, 505.3P) | in house |
| Tensile Strength | 140 N/mm² (505.2); 150 N/mm² (505.3, 505.4); 100 N/mm² (505.2P); 110 N/mm² (505.3P) | ISO 527 |
| Flexural Strength | >160 N/mm² (505.2); >180 N/mm² (505.3); >200 N/mm² (505.4); >100 N/mm² (505.2P, 505.3P) | ISO 178 |
Thermal Properties
| Property | Value | Test Method |
| Heat Resistance, Continuous Service | 500°C (505.2, 505.3, 505.4); 700°C (505.2P, 505.3P) | — |
| Heat Resistance, Intermittent Service | 800°C (505.2, 505.3, 505.4); 1000°C (505.2P, 505.3P) | — |
| Heat Loss at 500°C | <1% (505.2, 505.3, 505.4, 505.2P); <2% (505.3P) | IEC 371-2 |
| Heat Loss at 700°C | Not specified (505.2, 505.3, 505.4); <2% (505.2P, 505.3P) | IEC 371-2 |
| Thermal Expansion, Perpendicular to Layer | 100 ×10⁻⁶/K (all grades) | — |
| Thermal Expansion, Parallel to Layer | 10 ×10⁻⁶/K (all grades) | — |
Electrical Properties
| Property | Value | Test Method |
| Dielectric Strength | >25 kV/mm (all grades) | IEC 243 |
| Insulation Resistance, 23°C | >10¹⁷ Ω·cm (all grades) | IEC 93 |
| Insulation Resistance, 550°C | >10¹² Ω·cm (all grades) | IEC 93 |
Compliance
- UL-94V-O — Compliant (E67143 M)
- IEC 371-3-3 — Compliant
- Heating elements for industrial and household appliances
- Automatic toaster heating elements requiring low-smoke, blister-free performance
- Hair dryer, hair setter, iron, and tumble dryer heating elements
- Band heaters and nozzle heaters
- Punched or imprinted heating element components requiring smooth, detailed surfaces
Common industries: Household appliance manufacturing, industrial heating element manufacturing, electrical component manufacturing.
Mica Fire Barrier Sheet – Standard is a family of rigid mica heater-plate laminates built from approximately 90% Cogebi Muscovite or Phlogopite mica bonded with an in-house-developed, high-temperature-resistant silicone resin. The series is designed to deliver reliable electrical insulation under sustained high-temperature exposure, and is offered in five grades so that fabricators can match density, surface finish, and heat rating to the specific heating-element application: 505.2 is a low-smoke, blister-free Muscovite grade built to withstand repeated extreme temperature cycling; 505.3 is the general-purpose Muscovite grade for standard heating elements; 505.4 is a higher-density Muscovite grade with a smoother surface suited to detailed punching and imprinting; and 505.2P and 505.3P are Phlogopite grades that trade some mechanical strength for softer, more heat-resistant performance at higher continuous and intermittent service temperatures.
Across the series, the material shows low water absorption (<1%), high dielectric strength (>25 kV/mm), and high insulation resistance both at room temperature (>10¹⁷ Ω·cm at 23°C) and at elevated temperature (>10¹² Ω·cm at 550°C), with heat loss held under 1–2% depending on grade and test temperature. Mica Fire Barrier Sheet – Standard can be readily punched into strips and parts according to drawings; tooling for punching difficult geometries should be fitted with spring-loaded holddown plates. The material has an unlimited shelf life when stored in a dry place at room temperature. Compliant with UL-94V-O (E67143 M) and IEC 371-3-3.
What differentiates the Mica Fire Barrier Sheet - Standard 505.2P and 505.3P Phlogopite grades from the 505.2, 505.3, and 505.4 Muscovite grades?
The Phlogopite grades (505.2P, 505.3P) are softer and more heat resistant, rated for continuous service at 700°C and intermittent service to 1000°C, making them suited to extreme high-temperature applications. The Muscovite grades (505.2, 505.3, 505.4) run cooler (500°C continuous / 800°C intermittent) but deliver higher tensile and flexural strength, with 505.4 offering the highest density and smoothest surface for punching highly detailed pieces or imprinting.
Why does dielectric strength matter for Mica Fire Barrier Sheet - Standard in heating element applications?
Mica Fire Barrier Sheet - Standard is designed to provide outstanding electrical insulation at high temperature in heating elements for industrial and household appliances. Its dielectric strength of greater than 25 kV/mm, together with insulation resistance exceeding 10¹⁷ Ω·cm at 23°C and 10¹² Ω·cm at 550°C, ensures the laminate maintains reliable electrical isolation even as the heating element reaches its rated operating temperature.
What is the service temperature range for Mica Fire Barrier Sheet - Standard?
intermittent service. Phlogopite grades (505.2P, 505.3P) are rated for 700°C continuous service and 1000°C intermittent service.
Is Mica Fire Barrier Sheet - Standard suitable for flame-rated electrical insulation environments?
Yes. Mica Fire Barrier Sheet - Standard is certified to UL-94V-O (E67143 M) and conforms to IEC 371-3-3.
How should Mica Fire Barrier Sheet - Standard be specified?
Specify grade (505.2, 505.3, 505.4, 505.2P, or 505.3P), thickness, sheet dimensions or punched part drawing, compliance requirements, and dimensional tolerances.
