In This Article
Key Takeaways
- ◆NdFeB and SmCo have different property ranges; use the manufacturer’s grade data rather than a universal temperature crossover.
- ◆Evaluate the working point and reverse field at the required temperature.
- ◆SmCo’s corrosion behaviour does not establish implant, vacuum or chemical suitability.
- ◆Compare quotations for equivalent qualified parts; no universal 2026 price ratio is established.
- ◆Grade suffixes and F/N/D series labels do not establish composition or export clearance. Classify the actual item and transaction with the exporter, including the parties, end use and route. See the export-control guide.
Compare material specifications
NdFeB and SmCo are different permanent-magnet families. Br, coercivity, energy product and temperature coefficients vary by composition and grade. A family-wide maximum cannot substitute for the actual property window. Educational high-grade examples do not establish Mainrich supply.
Use the hot curves
Evaluate the required flux and reverse-field margin at temperature in the intended geometry. SmCo can be considered where thermal stability is important, but no fixed temperature alone decides the selection. Both materials require application-specific evaluation.
Check the environment
Confirm corrosion, handling and mounting requirements for the actual alloy and exposure. SmCo can be used uncoated in some environments, but it is not immune to every chemical or automatically suitable for an implant. Medical-device biological evaluation applies to the finished device, as described in FDA guidance.
Compare finished costs
Obtain equivalent drawing-specific quotations including finishing, inspection, tooling and supply terms. The earlier material price ranges and country-wide premiums are not current buying guidance. A material price per MGOe alone cannot capture the installed cost of a motor design.
Export classification
Announcement 18 of 4 April 2025 lists specified rare-earth items, including SmCo permanent-magnet materials and NdFeB permanent-magnet materials containing Tb or Dy. The notice does not establish a generic combined Dy+Tb ≤0.1 wt% safe harbour.
Trace content and uncertain items require classification; a grade suffix cannot decide the outcome. MOFCOM’s 16 September 2025 FAQ says the described rotor/stator components with magnets fixed into or onto iron cores or steel plates, including specified more integrated constructions, are generally outside Announcement 18. This qualified guidance does not clear every assembly or remove other applicable controls.
Confirm the proposed supply route
Mainrich’s sintered NdFeB range is N30 to N56, with no AH grades. The top grade depends on the temperature series: N56, N54M, N52H, N52SH, N50UH and N45EH. Grades up to N52SH can be made without a Chinese export licence, so we offer those first; UH and EH grades need a licence, applied for per order.
Confirm the grade, suffix, geometry and production route for each drawing. This summary does not offer every combination; grades outside it in educational examples are not Mainrich supply offers. Mainrich does not supply SmCo; compare any SmCo candidate against its own manufacturer's data. Check the current certificate for the actual manufacturing entity, address and activity. Agree PPAP level and required reports for the order; a network relationship does not certify every plant or assembly.
Frequently Asked Questions
Which material is better at high temperature?
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Evaluate the required flux and reverse-field margin at temperature in the intended geometry. SmCo can be considered where thermal stability is important, but no fixed temperature alone decides the selection. Both materials require application-specific evaluation.
Does SmCo need a coating?
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Confirm corrosion, handling and mounting requirements for the actual alloy and exposure. SmCo can be used uncoated in some environments, but it is not immune to every chemical or automatically suitable for an implant. Medical-device biological evaluation applies to the finished device, as described in FDA guidance.
Is SmCo always more expensive?
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Obtain equivalent drawing-specific quotations including finishing, inspection, tooling and supply terms. The earlier material price ranges and country-wide premiums are not current buying guidance. A material price per MGOe alone cannot capture the installed cost of a motor design.
Does switching to SmCo establish export clearance?
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Announcement 18 of 4 April 2025 lists specified rare-earth items, including SmCo permanent-magnet materials and NdFeB permanent-magnet materials containing Tb or Dy. The notice does not establish a generic combined Dy+Tb ≤0.1 wt% safe harbour. Trace content and uncertain items require classification; a grade suffix cannot decide the outcome. Grade suffixes and F/N/D series labels do not establish composition or export clearance. Classify the actual item and transaction with the exporter, including the parties, end use and route. See the export-control guide.
Can I use an educational grade as a Mainrich supply offer?
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Mainrich’s sintered NdFeB range is N30 to N56, with no AH grades. The top grade depends on the temperature series: N56, N54M, N52H, N52SH, N50UH and N45EH. Grades up to N52SH can be made without a Chinese export licence, so we offer those first; UH and EH grades need a licence, applied for per order. Confirm the grade, suffix, geometry and production route for each drawing. This summary does not offer every combination; grades outside it in educational examples are not Mainrich supply offers.
Send the operating duty, required field and drawing for a material and supply-route review.
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