Static magnet

Buyers must prioritize the Magnetic Grade (e.g., N35 to N52 for Neodymium) and Remanence (Br), which determines the flux density. It is crucial to verify the Maximum Operating Temperature; for instance, standard NdFeB magnets lose magnetism above 80°C, whereas Samarium Cobalt (SmCo) can withstand up to 350°C. Additionally, specify the Coating/Plating (Ni-Cu-Ni, Zinc, or Epoxy) to prevent oxidation, especially in humid environments.

Request a Hysteresis Graph (Demagnetization Curve) from the supplier to verify magnetic properties. Implement a sampling plan where Gaussian values are measured using a calibrated Gaussmeter or Fluxmeter. Ensure the supplier adheres to ISO 9001 quality management systems and provides a Certificate of Analysis (CoA) for every batch to guarantee that the Magnetic Force meets your specific pull-strength requirements.

For the EU market, magnets must comply with REACH and RoHS directives to ensure they are free from hazardous substances. If the magnets are used in toys or consumer electronics, they must meet EN71 or ASTM F963 safety standards to prevent ingestion hazards. For medical applications, ISO 13485 certification is highly recommended to ensure biocompatibility and manufacturing traceability.

For high-volume applications where space is not a constraint, Ferrite (Ceramic) magnets offer the best economic feasibility due to low raw material costs. However, if high performance and miniaturization are required, Neodymium (NdFeB) is the industry standard, though prices are subject to Rare Earth market fluctuations. Always evaluate the Energy Product (BHmax) to determine the most efficient material for your specific application.

Magnets are classified as Dangerous Goods (Class 9) in air transport if their magnetic field strength exceeds 0.00525 gauss at 4.6 meters. You must ensure the supplier uses Magnetic Shielding Packaging (iron sheets and foam) and provides a Magnetic Inspection Report from a certified third-party agency to comply with IATA regulations.

Utilize Secure Payment Terms such as Escrow services or Letters of Credit (L/C). Before placing a large order, conduct a Factory Audit or hire a third-party inspector to verify the supplier's production capacity and Sintering equipment. On platforms like Made-in-China.com, prioritize Audited Suppliers who have undergone on-site verification to reduce the risk of receiving sub-standard materials.

Negotiate based on the Raw Material Index for Neodymium and Dysprosium. Request a Price Breakdown that separates material costs from machining and coating costs. For long-term contracts, seek Volume-Based Rebates or a Fixed-Price Agreement for a set period to protect your supply chain from the volatility of Rare Earth metal prices.

The most common pitfall is ignoring Dimensional Tolerances; magnets are brittle and usually ground, so standard tolerances are typically +/-0.05mm to +/-0.1mm. Ensure the Magnetization Direction (Axial, Radial, or Multi-pole) is clearly defined in the technical drawings, as incorrect orientation will render the product unusable for your assembly.