Key takeaways
- NiCuNi has nickel, copper and nickel layers. Specify the complete stack and thickness.
- An epoxy designation must identify the formulation, application method and any base plating.
- Compare salt-spray results only with the same specimen preparation, conditions and failure criterion. ASTM B117 does not assign product acceptance hours.
- Adhesive performance depends on the actual coating, surface preparation, adhesive and cure.
Overview
Overview
Coating performance belongs to a complete protective system. Two epoxy coatings or NiCuNi stacks can have different thickness, preparation and test results. Treat catalogue hours as source-specific data until the full system and acceptance criterion are identified.
Side-by-side
Side-by-Side Comparison
Reference properties and design questions. A count of comparison points does not establish a material or supplier recommendation.
| Criterion | NiCuNi Coating | Epoxy Coating |
|---|---|---|
| Coating construction | Nickel/copper/nickel plating | Specified epoxy formulation and any base layers |
| Thickness | Specify each layer and total finished allowance | Specify polymer and base-layer thickness |
| Salt-spray acceptance | Agreed method, exposure and failure criterion | Agreed method, exposure and failure criterion |
| Adhesive bonding | Qualify preparation, adhesive and cure | Qualify preparation, adhesive and cure |
| Wear and handling | Check scratches, edge coverage and assembly damage | Check scratches, edge coverage and assembly damage |
| Temperature | Qualify the finished protective system | Qualify formulation, cure and finished system |
| Magnetic circuit | Nickel layers can affect the circuit; include coating geometry | Include coating thickness and magnetic working gap |
| Cost | Current part quotation | Current part quotation |
Confirm source conditions and the actual part requirements before using reference values as acceptance limits.
Use cases
Conditions for considering each option
When NiCuNi Coating wins
- The specified plating passes the part’s exposure and assembly tests.
- Its finished dimensions and surface meet the retention design.
When Epoxy Coating wins
- The specified epoxy system passes the environmental and bonding tests.
- Its qualified insulation or barrier properties serve the assembly design.
How to choose
Decision Framework
Decision framework
Define exposure, temperature, assembly loads and finished dimensions. Agree the coating stack and test criterion, then compare results for equivalent specimens. Qualify the bond line separately. A coating name does not establish corrosion life or adhesive strength.
Specs
Related NdFeB Grades
N42SH
150°C classN42SH reference: 40–43 MGOe at 20°C, with a nominal 150°C temperature class.
Reference; drawing review required
N45SH
150°C classN45SH reference: 43–46 MGOe at 20°C, with a nominal 150°C temperature class.
Reference; drawing review required
N48SH
150°C classN48SH reference: 45–48 MGOe at 20°C, with a nominal 150°C temperature class.
Reference; drawing review required
N45UH
180°C classN45UH reference: 43–46 MGOe at 20°C, with a nominal 180°C temperature class.
Reference; drawing review required
Industries
Related Applications
EV Motors
NdFeB magnet design inputs for permanent-magnet traction motors, auxiliary drives and e-axles.
Wind Turbines
NdFeB block and tile design inputs for permanent-magnet wind generators.
Industrial Automation
NdFeB magnets for stepper motors, servo drives, linear actuators, magnetic couplings, and factory automation equipment across European and North American manufacturing.
Questions
Frequently Asked Questions
What is the difference between NiCuNi and epoxy?
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NiCuNi is a three-layer metal plating system. Epoxy is a polymer coating that may use a base plating. Specify the full system, including preparation and layer thicknesses, before comparing performance.
Which coating should I use outdoors?
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Qualify the complete coating and enclosure against the expected water, salt, UV and temperature exposure. Salt-spray hours alone do not predict outdoor service life.
Can epoxy-coated magnets be bonded into a rotor?
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They can be evaluated for that use. Test the specified coating, surface preparation, adhesive and cure under representative shear, temperature and fluid exposure. Sharing the word epoxy does not guarantee bond strength.
Need help deciding?
Share your drawing, operating conditions and acceptance requirements for review. Human response within 1 business day.