01 / Overview
Application Overview
Medical equipment can use NdFeB in actuators, sensor targets and some permanent-magnet MRI main-field arrays. Superconducting MRI uses a different main-field source; gradient fields are generated by current-driven coils. Implant and tissue-contact uses need a finished-device qualification programme.
02 / Material
Why NdFeB for Medical Devices
NdFeB can provide high field in a compact mechanism or permanent-magnet array. Medical suitability depends on device design, exposure and qualification, including the encapsulation and retention system.
03 / Specifications
Key Design Requirements
Biological evaluation
Assess the finished device for its intended contact and duration. A coating material test does not establish the biological safety of the assembled device.
Traceability
Agree material, coating and lot records needed for the device risk and quality system.
Sterilization
Validate the actual process, cycle count and exposure for the finished magnet, coating and assembly. Include magnetic loss and coating integrity.
Dimensions and field
Set inspection limits from the mechanism or field-array design and confirm them with the production route.
04 / Grade Selection
NdFeB grade references for Medical Devices
These educational references do not establish supply or thermal suitability. Review the actual hot curves, load line, opposing field and duty cycle before selecting a grade.
N45
80°C class · StandardN45 reference: 43–46 MGOe at 20°C, with a nominal 80°C temperature class.
Reference; drawing review required
N48
80°C class · StandardN48 reference: 45–48 MGOe at 20°C, with a nominal 80°C temperature class.
Reference; drawing review required
N50
65°C class · StandardN50 reference: 47–50 MGOe at 20°C, with a nominal 65°C temperature class.
Reference; drawing review required
N45SH
150°C class · Super High Temperature (SH)N45SH reference: 43–46 MGOe at 20°C, with a nominal 150°C temperature class.
Reference; drawing review required
N48SH
150°C class · Super High Temperature (SH)N48SH reference: 45–48 MGOe at 20°C, with a nominal 150°C temperature class.
Reference; drawing review required
05 / Geometry
Typical Magnet Configurations
- Blocks in permanent-magnet MRI main-field arrays
- Magnets in medical equipment motors
- Encapsulated magnets in device design studies
- Disc or block sensor targets
Typical dimensions
Dimensions and tolerances follow the device drawing. Main-field arrays and miniature mechanism magnets require separate qualification.
06 / Engineering Notes
Design & Procurement Considerations
- 01Parylene is a candidate barrier coating. It does not make a magnet MR safe or establish a hermetic implant enclosure.
- 02Review the device quality system and supplier responsibilities against the actual regulatory pathway; ISO 13485 addresses medical-device quality management.
- 03Validate adhesion, barrier integrity and magnetic output after the intended cleaning or sterilization cycles.
- 04For an MRI array, field homogeneity depends on geometry, temperature control, shimming and the completed field map.
07 / Resources
Further Reading
Technical
NdFeB Magnet Coatings: Specify and Test the Complete System
Compare NiCuNi, epoxy, zinc and parylene against the actual environment, assembly and inspection requirements.
Buyer's Guide
Qualifying an NdFeB Supplier for Automotive and Robotics
Agree the quality and technical evidence for the programme, then verify the actual manufacturing and export route.
Technical
NdFeB and SmCo: Compare the Actual Material and Duty
Compare hot magnetic curves, environmental exposure and the finished-part cost. Neither material name determines every application limit.
08 / Compare
Related Engineering Comparisons
FAQ / Questions
Frequently Asked Questions
Are NdFeB magnets biocompatible?
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Unprotected NdFeB can corrode in biological fluids. Coating or encapsulation is part of a device-specific protection system. Biological evaluation must cover the finished device and intended contact; parylene alone does not establish implant suitability or hermeticity.
What NdFeB grade is used in MRI machines?
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Some permanent-magnet MRI main-field systems use NdFeB arrays. The designer selects material against the required field, stability and geometry. Superconducting main-field systems use different technology, and MRI gradient fields come from current-driven coils.
Can NdFeB magnets be sterilized?
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Qualification must address the specified sterilization method, cycle count and finished assembly. Test magnetic output, coating integrity and other acceptance criteria after exposure. No coating designation guarantees survival of every steam, ethylene-oxide or radiation process.
Does parylene coating make a magnet MRI compatible?
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No. FDA guidance calls for device-level assessment and labeling for the MR environment. A coating does not remove magnetic force, torque, heating or image-artifact risks.
Start an RFQ
Request a Quote for Medical Devices
Share your application, target dimensions, operating temperature, and annual volume. We respond within 1 business day. Grade, production route and inspection requirements are confirmed before a part-specific supply promise.