Mu-ferro/mu-metal foil
Mu-ferro(mu-metal or Permalloy) foil and tape, is a specialized material designed for effective low-frequency (LF) magnetic field shielding. It is highly valued for its exceptional magnetic permeability and flexibility, making it ideal for various shielding applications.
Key Features
- High permeability
- Magnetic shielding
- Bending, cutting, and attaching double-sided tape are possible.
Custom Manufacturing
Custom Mu-ferro/mu-metal foil
Mu-ferro foil and tape can be customized to meet specific application requirements. Customization options include:
- Width and Length: Specify the width up to 150 mm and length up to 100 meters. Custom widths and lengths can be produced upon request to suit particular applications.
- Thickness: Depending on the shielding needs, different thicknesses such as 0.005~0.05mm(tolerance within ±5%) can be produced.
Product Specs
Material Properties
It is a high-permeability alloy primarily used for shielding low-frequency magnetic fields. It typically consists of nickel, iron, copper, and chromium among other metals, with the exact composition adjustable based on various applications.
| Properties | Item | Data | Remarks |
|---|---|---|---|
| Magnetic | Saturation polarization | 0.74 T | 20°C |
| Saturation magnetostriction | ca. 1 ppm | ||
| Curie temperature | 700°F (370°C) | ||
| AC Magnetic | Initial permeability(60Hz) at B=40G [μ(40G)] | 100,000 | |
| μ at H= 4mA/cm [μ4] | 250,000 | ||
| Max. permeability [μmax] | 350,000 | ||
| Coercivity [Hc] | 20 mOe (15 mA/cm) | ||
| Saturation induction, Magnetic flux density [Bs] | 7,400 G (0.74 T) | ||
| Physical | Mass density | 8.7 g/cm3 | ESQ-612-38 |
| Electrical resistivity | 0.6 x 10-6 Ohm m | ||
| Coefficient of thermal expansion | 13.5 x 10-6 K-1 | 20~100°C | |
| Mechanical | Hardness (HV) | 270~420 | |
| Tensile strength | 1280 N/mm2 | > 0.2mm | |
| Yield strength | 1230 N/mm2 | ||
| Elongation | 1~3 % |
Advantages
Mu-ferro foil works well for shielding low-frequency magnetic fields. Due to the low electrical resistance it shields both low-frequency electric fields (LF) and high-frequency fields (HF). Comparable with Mu-Metal specifications.
- Ease of Handling: Easily cut with scissors and applied to various surfaces.
- Effective Shielding: Provides up to 14 dB attenuation for LF magnetic fields and up to 100 dB at 1 GHz for HF fields when multiple layers are used.
- Versatile Applications: From cable shielding to large-area applications in military and aerospace industries.
Applications
Cover the magnetic field parts with permalloy foil, or protect the sensor from external magnetic fields by inserting the sensor control in the permalloy case.
- Electronic Devices: Prevents EMI in sensitive components and systems.
- Medical Equipment: Essential in MRI machines and other diagnostic devices to minimize external magnetic interference.
- Aerospace and Automotive: Used to shield critical avionics and automotive electronics.
- Research and Development: Utilized in scientific instruments like electron microscopes and magnetic sensors for accurate readings.
Dimensions Measurement Guide
Mu-ferro foil is a thin foil; its thickness is only 0.005~0.05mm, tolerance within ±5%. It combines excellent soft magnetic properties with unusual mechanical hardness and flexibility. This means that tight bends can be realised with only very slight impairment of permeability. The fine strip thickness and comparatively low electrical conductivity permit effective shielding even of higher-frequency fields. The roll can be ordered ordered up to 100 meter in length and a width up to 50 meter.
How to shield the magnetic field
It is most effective to enclose the source or affected parts of the magnetic field shield completely. Still, the shielding effect can be obtained even if only the specific part is covered or the cover type is installed, as shown above.
When you wrap a cylindrical shape or cover a rectangular housing, be careful not to make a gap between the joint and between the body and the lid.
