Brief Introduction
Wangling F4BME series are PTFE glass fabric copper-clad laminates that share the same dielectric layer as the F4BM series but utilize Reverse Treated Foil (RTF) copper. This configuration delivers excellent Passive Intermodulation (PIM) performance, more precise circuit control, and lower conductor loss, making it ideal for applications with stringent PIM requirements. F4BME255 is the variant with a dielectric constant of 2.55.
Technical Features & Benefits
Selectable Dielectric Constant (Dk) from 2.17 to 3.0; Dk 2.55 with customizable options available
Low dissipation factor (Df 0.0013 @ 10GHz, 0.0018 @ 20GHz)
Excellent PIM performance (≤ -159 dBc) due to Reverse Treated Foil (RTF) copper
More precise line control and lower conductor loss
Good dimensional stability and enhanced size control
Radiation resistance and low outgassing
Commercial, high-volume, cost-effective production
UL 94 V-0 flammability rating
Long-term operating temperature: -55°C to +260°C
Very low moisture absorption (≤0.08%)

Typical Properties:F4BME 245
| Properties | Test Conditions | Unit | F4BME255 |
|---|---|---|---|
| Electrical Properties | |||
| Dielectric Constant (Typical) | 10 GHz | – | 2.55 |
| Dielectric Constant Tolerance | – | – | ±0.05 |
| Dissipation Factor (Typical) | 10 GHz | – | 0.0013 |
| 20 GHz | – | 0.0018 | |
| Temperature Coefficient of Dk | -55°C to 150°C | ppm/°C | -110 |
| Peel Strength | 1 oz. F4BME | N/mm | >1.6 |
| Volume Resistivity | Normal Condition | MΩ·cm | ≥6×10⁶ |
| Surface Resistance | Normal Condition | MΩ | ≥1×10⁶ |
| Dielectric Strength (Z-direction) | 5 kW, 500 V/s | kV/mm | >25 |
| Breakdown Voltage (XY-direction) | 5 kW, 500 V/s | kV | >34 |
| PIM Performance | Only for F4BME series | dBc | ≤ -159 |
| Thermal & Mechanical Properties | |||
| CTE | XY-direction, -55°C to 288°C | ppm/°C | 16~21 |
| Z-direction, -55°C to 288°C | ppm/°C | 173 | |
| Thermal Stress | 260°C, 10s, 3 cycles | – | No Delamination |
| Water Absorption | 20±2°C, 24 hours | % | ≤0.08 |
| Density | Room Temperature | g/cm³ | 2.25 |
| Long-term Operating Temperature | – | °C | -55 to +260 |
| Thermal Conductivity | Z-direction | W/(m·K) | 0.33 |
| Flammability Rating | – | UL-94 | V-0 |
| Material Composition | – | – | PTFE, Glass Fiber Cloth; F4BME uses Reverse Treated Foil (RTF) copper |
Application Areas
Microwave, RF, Radar
Phase Shifters, Passive Components
Power Dividers, Couplers, Combiners
Feed Networks, Phased Array Antennas
Satellite Communication, Base Station Antennas
Avalable Configurations
Copper Foil Options for F4BME: Reverse Treated Foil (RTF) Copper. Available thicknesses: 0.5 oz (0.018mm), 1 oz (0.035mm).
Standard Panel Sizes Available:
460 × 610 mm
500 × 600 mm
850 × 1200 mm
914 × 1220 mm
1000 × 1200 mm
Available Thicknesses & Tolerances (Conventional):
Thickness (mm): 0.1 (core), 0.127 (core), 0.2, 0.25, 0.5, 0.508, 0.762, 0.8, 1.0, 1.5, 1.524, 1.575, 2.0, 2.5, 3.0, 4.0, 5.0, 6.0, 8.0, 10.0, 12.0.
Corresponding tolerances range from ±0.01mm to ±0.20mm.
Note: For Dk ≤ 2.65, minimum core thickness is 0.1mm.
F4BME Series with Metal Core (Aluminum/Copper Base):
Models: F4BME*-AL (Aluminum base), F4BME*-CU (Copper base)
Serves for shielding or heat dissipation
Example: F4BME255-AL represents F4BME255 with aluminum base; F4BME255-CU represents F4BME255 with copper base
Standard sizes available: 460×610 mm, 460×305 mm; other sizes upon request