Arc magnet

When purchasing arc magnets, you must specify the Magnetic Grade (e.g., N35 to N52 for Neodymium, or Y30 to Y35 for Ferrite) as this determines the magnetic flux density. Pay close attention to Dimensional Tolerances, typically requiring ±0.05mm to ±0.1mm for high-speed motor applications. Additionally, define the Coating/Plating (such as Ni-Cu-Ni, Zinc, or Epoxy) to prevent oxidation, and confirm the Maximum Operating Temperature (e.g., 80°C for N grade, up to 200°C for EH grade) to ensure stability under load.

Compatibility is determined by the Radian (Degree of Arc), Outer Diameter (OD), and Inner Diameter (ID). You should provide the supplier with a technical CAD drawing to verify the fit. Furthermore, specify the Magnetization Direction (e.g., Diametrically magnetized, Radial, or Multi-pole) because an incorrect orientation will render the magnet useless for your specific motor assembly.

Ensure the supplier complies with ISO 9001 for quality management and IATF 16949 if you are sourcing for automotive applications. For environmental and safety compliance, the magnets must meet RoHS and REACH standards to ensure they are free from hazardous substances. Request a Hysteresis Curve (Demagnetization Curve) report to verify the actual magnetic properties against the advertised grade.

Arc magnets are primarily used in Permanent Magnet Motors (PMM), Electric Vehicle (EV) drivetrains, wind turbine generators, and industrial pumps. They are also essential components in power tools and household appliances like washing machine motors. Understanding the specific RPM and heat environment of your scenario is critical for selecting the right material, such as Neodymium (NdFeB) for high performance or Samarium Cobalt (SmCo) for extreme heat resistance.

Magnets are classified as 'Dangerous Goods' for air freight because they can interfere with aircraft navigation systems. You must ensure the supplier provides Magnetic Shielding Packaging (using iron sheets and foam) and obtains a Non-Magnetic Inspection Report from recognized authorities like DGM. For sea freight, ensure the packaging is moisture-proof to prevent corrosion during long-duration transit.

To avoid 'grade substitution' (e.g., receiving N33 instead of N38), use Made-in-China.com's Secured Trading services. Always request a pre-shipment inspection (PSI) where a third party tests the Surface Gauss and Pull Force. It is also advisable to start with a sample order to conduct a destructive test and verify the internal grain structure of the magnet.

Since raw material prices for Rare Earth elements (like Neodymium and Dysprosium) fluctuate daily, negotiate a price adjustment formula based on market indices. For bulk orders, aim for a 10-15% discount by committing to an annual volume while requesting staggered shipments. Always clarify the Incoterms (e.g., FOB or DAP) to avoid hidden logistics surcharges.

Check for Anti-Dumping Duties (ADD) that may apply to magnets originating from certain regions when imported into the EU or USA. Ensure the supplier provides a correct HS Code (typically 8505.11) to avoid customs delays. Working with Verified Suppliers on Made-in-China.com can help ensure that all Certificate of Origin documentation is handled professionally to leverage applicable trade agreements.