MuMetal® Magnetic Shielding
Premium Low-Frequency Magnetic Shields
MuMetal® is a proprietary high-permeability Nickel-Iron alloy engineered for the attenuation of low-frequency magnetic fields.
As the U.S. sales and technical support arm of Magnetic Shields Limited, Magnetic Shields USA provides access to the world’s largest stock holder of MuMetal sheet material, which means we can react to the demands of a fast-paced, ever-changing marketplace
Typical Applications
Quantum Computing & Sensing
Medical Imaging (MEG, MCG)
Aerospace & Defense Electronics
Precision Measurement & Test Equipment
Audio and Transformer Shielding
Available Forms
- Fabricated Cans, Boxes & Sleeves
- Custom-Designed Shielding Assemblies
- Magnetically Shielded Rooms
Why Choose MuMetal® Shields from Magnetic Shields USA?
Ultra-High Permeability for superior shielding performance
Hydrogen Annealed In-House to optimize magnetic properties
Rapid U.S. Delivery Reduce development time and risk with accurate pre-production modeling
Custom Fabrication Available for shielding cans, enclosures, and assemblies
Advanced Low-Noise Magnetic Shielding with Active Compensation
The GA4 Hybrid Shield combines the power of four-layer passive MuMetal® shielding with nine flexible active coils and integrated demagnetization for precise control of magnetic fields.
This system is engineered for ultra-sensitive environments requiring noise floors below 15 fT/√Hz. Now available in the U.S. via Magnetic Shields USA.
Features
4-layer MuMetal® passive shielding for robust low-frequency attenuation
9 active flexible PCB coils including gradient and second-order nulling
Integrated degaussing coils for easy demagnetization
Removable end caps with handles and secure latches for easy access
Optimized for minimal Johnson noise in quantum and biomedical measurements
Applications
- Quantum sensing and computing
- Low-noise biomedical measurements
- Research-grade magnetometry
- Aerospace and defense instrumentation
Contact Magnetic Shields USA today for delivery options.
Specifications
| Feature | Imperial (inches) | Metric (mm) |
| Internal Dimensions | 7.87 in (ID) × 11.81 in | 200 mm × 300 mm |
| External Dimensions | 11.93 in (OD) × 18.98 in | 303 mm × 482 mm |
| Shielding Layers | 4 layers of MuMetal® | — |
| Noise Floor | <15 fT/√Hz (1–100 Hz) | — |
| DC Field (Passive Only) | 1.68 nT | — |
| DC Field (Active On) | 0.23 nT | — |
| 10 Hz Shielding Factor (Axial) | 4,100,000 | — |
| 10 Hz Shielding Factor (Transverse) | 39,200,000 | — |
We design and manufacture custom and modular magnetically shielded rooms to meet the demanding requirements of spectroscopy, fundamental physics, and precision measurement research.
Each project begins with a detailed magnetic field survey to tailor the shielding and room layout.
Features
High-permeability MuMetal® layers combined with electrically conductive RF shielding
Modular construction for rapid deployment or fully bespoke builds
Optional active field cancellation systems
Integrated power, data ports, and field-free lighting
Applications
- Nuclear Magnetic Resonance (NMR) spectroscopy
- Quantum magnetometry
- Fundamental physics experiments
- Biomedical imaging
Contact Magnetic Shields USA for project planning and site survey assistance.
MuCans are precision-fabricated MuMetal® magnetic shielding enclosures designed to protect transformers, inductors, and sensitive electronics from low-frequency magnetic interference.
Manufactured to ASTM A753 Alloy 4 standards and supplied fully annealed, they provide exceptional magnetic field attenuation in compact form factors.
Features
High permeability ASTM A753 Alloy 4 MuMetal®
Custom lids and apertures available
Hydrogen annealed for peak magnetic performance
Suitable for board-level and enclosure shielding
Applications
- Transformer shielding in aerospace and defense systems
- Medical imaging electronics protection
- Power supply EMI mitigation
- High-precision measurement equipment
Request a custom quote from Magnetic Shields USA for your MuCan requirements.
Quantum computing qubit stabilization
Ultra-precise atomic and ion clocks
Quantum sensors for navigation, defense, and research
High-resolution quantum imaging and simulation
Contact us to explore shielding options for your quantum technology project.
Why Choose Magnetic Shields USA?
Fast access to engineered solutions and prototypes
Collaborative engineering support tailored to quantum device needs
Proven shielding performance in global quantum research facilities
For applications operating at cryogenic temperatures down to 4 Kelvin, we offer CRYOPHY® magnetic shielding, a specialized nickel-iron-molybdenum alloy optimized for stable magnetic permeability in extreme cold.
Material Selection by Temperature
| Temperature | Recommended Alloy |
| Above -40 °F (-40 °C) | MuMetal® |
| Below -40 °F (-40 °C) | CRYOPHY® |
CRYOPHY® Features
Maintains permeability at 4K for superconducting and cryogenic research
Proprietary 36+ hour hydrogen annealing cycle
Thermal range: 392 °F to 2,102 °F (200 °C to 1,150 °C)
Permeability ~70,000 at 4 K (0.4 A/m applied field)
Applications
- Superconducting magnet systems
- Cryogenic particle detectors
- Quantum computing cryostats
- High-energy physics instrumentation
Contact Magnetic Shields USA to discuss cryogenic shielding needs and custom manufacturing.
high-accuracy MuMetal® toroidal cores
Each batch of MuMetal® toroidal cores is subject to rigorous quality control and stringent permeability testing before shipment.
Utilizing a broad range of winding machinery, Magnetic Shields Ltd produces toroidal cores with internal diameters (ID) starting at 1.97 inches (50 mm) and external diameters (OD) up to 39.37 inches (1,000 mm). Strip thicknesses range from 0.0039 inches (0.1 mm) to 0.0138 inches (0.35 mm). Cores can be supplied either cased or fixed to suit your application requirements.
Magnetic Shields USA offers high-accuracy MuMetal® toroidal cores manufactured by Magnetic Shields Ltd, a global leader in magnetic materials production.
Features
High-precision manufacturing with strict permeability testing
Wide size range from 1.97 in to 39.37 in OD
Multiple strip thickness options for customization
Available cased or fixed for ease of integration
Contact Magnetic Shields USA today to discuss your MuMetal® toroidal core requirements and receive expert engineering support tailored to your project.
Purpose-built, Site-Specific for MCG and imaging
The Heart Shield is a purpose-built magnetically shielded shield tailored for magnetocardiography (MCG), biomagnetic imaging, and other biomedical research requiring ultra-low magnetic interference environments.
Features
Three-layer MuMetal® shielding plus one aluminum RF layer
Integrated active axial field cancellation coil
Optional mechanical opening/closing mechanism
Power and signal feedthroughs with field-free lighting
Custom sizing based on site-specific field surveys
Applications
- Magnetocardiography (MCG)
- Biomagnetic diagnostics
- Neuroscience research labs
- Sensitive magnetic measurement environments
Schedule a consultation with Magnetic Shields USA for custom Heart Shield configurations.
Specifications
| Feature | Imperial (inches) | Metric (mm) |
| Internal Dimensions | Ø 41.54 in × 110.90 in | Ø 1,055 mm × 2,817 mm |
| External Dimensions | Ø 53.82 in × 121.46 in | Ø 1,367 mm × 3,085 mm |
| MuMetal® Layers | 3 layers | — |
| Aluminum RF Layer | 1 layer | — |
| Active Shielding | Axial field cancellation coil | — |
| Degaussing | Integrated demagnetization coils | — |
the worldwide standard for magnetic shielding
MuMETAL® is a high-permeability nickel iron alloy developed to provide maximum attenuation of low-intensity magnetic fields. Recognized worldwide as the standard for magnetic shielding performance, MuMETAL® is used in applications requiring stable, uniform low-field environments and minimal magnetic interference.
Manufactured to conform with ASTM A753 Alloy 4 and MIL-N-14411C Comp 1, MuMETAL® offers exceptional initial permeability, low coercivity, and high shielding efficiency when properly annealed.
Product Forms and Applications
MuMETAL® is available in sheet, plate, and coil forms to support a wide range of magnetic shielding and fabrication requirements:
- Sheet: 0.014 – 0.080 in (0.36 – 2.00 mm) — flexible and machinable for magnetic enclosures, cylinders, or formed shields
- Plate: 0.098 – 0.197 in (2.5 – 5.0 mm) — ideal for rigid structures or high-field attenuation barriers
- Coil: 0.002 – 0.031 in (0.05 – 0.79 mm) — suited for precision components and laminated assemblies
Common applications include shielding for sensors, instrumentation, magnetometers, CRTs, cryogenic systems, and EMI-sensitive electronics.
Material Properties
- Nominal Composition: ~80% Nickel, ~15% Iron, ~5% Molybdenum
- Maximum Permeability (µmax): ≥ 300,000 (H ≈ 0.4 A/m)
- Coercive Force (Hc): < 0.03 Oe (2.4 A/m)
- Saturation Flux Density (Bs): ≈ 0.8 Tesla (8,000 Gauss)
- Electrical Resistivity: ≈ 45 µΩ·cm
- Density: 8.7 g/cm³
- Annealing: A full magnetic anneal in a controlled hydrogen or vacuum atmosphere is required after fabrication to restore optimum permeability and achieve the highest shielding performance.
Fabrication and Processing
Supplied in soft temper stress-annealed condition for ease of forming, bending, and machining.
To achieve full magnetic performance, components must undergo a full magnetic anneal after any process that induces mechanical stress, such as welding, stamping, or rolling.
Stock sheet can be sheared or blanked to specified sizes upon request.
Performance and Compliance
- Attenuation: Highly effective for static and low-frequency AC magnetic fields
- Stability: Maintains permeability and structural integrity under normal service temperatures
- Conformance: ASTM A753 Alloy 4 / MIL-N-14411C Comp 1
Dimensional Range
- Thickness (Sheet): 0.014 – 0.080 in (0.36 – 2.00 mm)
- Width: 12 – 24 in (305 – 610 mm)
- Length: 15 – 120 in (381 – 3048 mm)
- Standard Gauges: 14, 20, 25, 30, 40, 50, 62, and 80 mil
- Custom sizes, plates, and coil lengths available on request
the worldwide standard for magnetic shielding
MuMETAL® Foil is a fully annealed, high-permeability nickel iron alloy designed for applications requiring the highest magnetic attenuation and shielding efficiency in low-intensity magnetic fields. Manufactured in accordance with ASTM A753 Alloy 4 and MIL-N-14411C Comp 1, MuMETAL® Foil exhibits exceptional initial permeability (µ) and uniform magnetic response across thin-gauge forms.
This precision foil is supplied in standard thicknesses from 0.002 in (0.051 mm) to 0.012 in (0.305 mm) and is used extensively in sensor calibration, instrumentation, low-field shielding, and electronic assembly applications.
Material and Processing
MuMETAL® Foil is supplied in the fully annealed condition to deliver maximum permeability and optimum shielding performance.
It retains its magnetic properties without additional heat treatment unless subjected to severe forming, welding, or mechanical stress, in which case a full magnetic anneal is recommended to restore peak performance.
- Nominal Composition: ~80% Nickel, ~15% Iron, ~5% Molybdenum
- Maximum Permeability (µmax): ≥ 300,000 (H ≈ 0.4 A/m)
- Saturation Flux Density (Bs): ≈ 0.8 Tesla (8,000 Gauss)
- Coercive Force (Hc): < 0.03 Oe (2.4 A/m)
- Resistivity: ≈ 45 µΩ·cm
- Density: 8.7 g/cm³
- Anneal Type: Full magnetic anneal for optimum shielding properties
Available Gauges and Dimensions
MuMETAL® Foil is available in stock gauges from 0.002 in (0.051 mm) to 0.012 in (0.305 mm).
Most commonly specified gauges:
- 0.002 in (0.051 mm)
- 0.008 in (0.203 mm)
- 0.012 in (0.305 mm)
Width Options: 8.00 in (203 mm) and 12.00 in (305 mm)
Width Tolerance: ±0.010 in (0.25 mm) standard, ±0.015 in (0.38 mm) with adhesive backing
Minimum Slit Width: 0.25 in (6.35 mm)
Adhesive Backing Option
All MuMETAL® Foil gauges are available with or without pressure-sensitive adhesive backing (PST) applied to one side for simplified installation.
- Adhesive Type: Acrylic-based, release liner-backed
- Operating Temperature Range: 32°F to 140°F (0°C to 60°C)
- Ideal for temporary shielding, prototyping, or non-welded applications
Fabrication and Services
- Supplied standard uncoated or with one-side adhesive backing
- Can be slit, sheared, or cut to custom widths and lengths
- Does not require re-annealing unless extensively formed or welded
Dimensional Summary
| Property | Imperial | Metric |
| Thickness Range | 0.002 – 0.012 in | 0.051 – 0.305 mm |
| Standard Widths | 8 in, 12 in | 203 mm, 305 mm |
| Minimum Slit Width | 0.25 in | 6.35 mm |
| Width Tolerance (Uncoated) | ±0.010 in | ±0.25 mm |
| Width Tolerance (With Adhesive) | ±0.015 in | ±0.38 mm |
| Operating Temperature (Adhesive) | 32°F – 140°F | 0°C – 60°C |
Performance and Compliance
- Magnetic Attenuation: Exceptional performance in static and low-frequency magnetic fields
- Thermal Stability: Maintains permeability within operating temperature range
- Material Standards: Conforms to ASTM A753 Alloy 4 / MIL-N-14411C Comp 1
- Surface Condition: Smooth rolled finish, suitable for lamination or bonding
Summary
MuMETAL® Foil provides the highest level of magnetic shielding performance available in a flexible, fully annealed thin alloy form.
Offered in multiple gauges with optional adhesive backing, MuMETAL® Foil is ideal for fine-tuning low-field environments, fabricating precision enclosures, and constructing experimental shielding systems where space and weight are limited.
The magnetic properties shown are typical of fully annealed MuMETAL® (ASTM A753 Alloy 4) and are provided for engineering reference only. Actual values depend on material thickness, fabrication process, and annealing parameters.
Get in Touch
Contact Magnetic Shields USA today to discuss your MuMetal® magnetic shielding requirements and receive expert engineering support tailored to your project.