Product Descriptions
High Temperature Resistance Arc Shape Neodymium Magnet – Engineered for Extreme Environments
For permanent magnet motors, generators, and sensors operating in high‑temperature environments, the high temperature resistance arc shape neodymium magnet offers a reliable, high‑performance solution. These sintered NdFeB arc segments are engineered with dysprosium and terbium additions to maintain high intrinsic coercivity (Hcj) at elevated temperatures, ensuring stable magnetic output and resistance to demagnetization even under continuous thermal stress. The curved geometry follows the rotor surface precisely, optimizing air‑gap flux distribution and delivering high torque density with minimal cogging. Typical applications include EV traction motors, turbocharger actuators, aerospace servos, and industrial drives where operating temperatures exceed 150°C. Our high temperature resistance arc shape neodymium magnets are manufactured from 100% virgin rare‑earth materials (purity ≥95%) with full process control – from vacuum melting and jet milling to sintering, heat treatment, and precision grinding. Available in N42SH (150°C), N40UH (180°C), and N38EH (200°C) grades, each magnet is precision ground on inner/outer radii, chord height, and end faces to tolerances of ±0.02‑0.03 mm, ensuring uniform air gaps and reduced vibration. Standard Ni‑Cu‑Ni triple plating (13‑18 μm) provides excellent corrosion resistance, while epoxy or Parylene coatings offer electrical insulation for high‑voltage systems. Every batch is 100% flux‑tested and dimensionally inspected, with full material traceability. Our IATF 16949 and ISO 9001 systems ensure consistent quality for automotive and industrial OEMs. Custom arc angles (30°‑150°), inner radii (10‑200 mm), thicknesses (2‑25 mm), and lengths (10‑200 mm) are available to match your rotor design.
Why High‑Temperature Arc Magnets Are Essential for Demanding Applications
Superior Thermal Stability
With dysprosium‑enhanced grain boundary diffusion, our high temperature resistance arc shape neodymium magnets maintain coercivity up to 200°C, ensuring reliable performance in turbochargers, EV motors, and aerospace actuators where standard N grades would rapidly demagnetize.
Optimized Motor Efficiency
The arc geometry minimizes air‑gap reluctance and reduces cogging torque, resulting in smoother rotation and higher overall motor efficiency – critical for EV range and servo precision.
Precision Grinding for Consistent Air Gaps
CNC rotary grinding achieves tight tolerances (±0.02‑0.03 mm) on all critical dimensions, ensuring uniform flux distribution and reducing rotor balancing effort during assembly.
Magnetic direction
Coating / Plating
Magnetic Grade Parameters
Quality Assurance – Engineered for Reliability in Extreme Conditions
Our vertically integrated facility ensures consistent quality for every high temperature resistance arc shape neodymium magnet. The process begins with vacuum induction melting of virgin rare earths (neodymium, iron, boron, and dysprosium/terbium). After jet milling to 3‑5 μm powder, the material is pressed in a segmented die under a magnetic field, sintered, and subjected to multi‑stage heat treatment to achieve maximum coercivity. Segments are ground on all critical surfaces using CNC rotary grinders, then plated with Ni‑Cu‑Ni in automated barrel lines. Final inspection includes 100% magnetic flux measurement (Helmholtz coil), dimensional check (CMM), and coating thickness verification (XRF). High‑temperature demagnetization tests are performed on sample batches to validate performance at rated temperatures. All shipments include material test certificates with full traceability. Our IATF 16949 and ISO 9001 systems ensure compliance with automotive and aerospace OEM standards.
Packaging & Logistics – Ready for Production Lines
Each arc segment is placed in a dedicated foam pocket within anti‑static trays to prevent edge chipping. Trays are stacked and packed into reinforced export cartons. Lead times: standard segments 10‑12 days; custom tooling 15‑20 days after drawing approval. Free samples available for qualified projects. We support just‑in‑time delivery and consignment stock for high‑volume OEMs.
FAQ
Q1: How are high-temperature arc neodymium magnets graded, and what do the suffix letters mean?
A1: The suffix letter indicates the maximum operating temperature. Standard grades (no suffix) work up to 80°C. M‑grade reaches 100°C, H‑grade 120°C, SH‑grade 150°C, UH‑grade 180°C, EH‑grade 200°C, and AH‑grade up to 220°C. For example, N48SH maintains stable flux up to ~150°C, while BMAG's AH series withstands 220°C without irreversible demagnetization. Choose the grade based on your motor's peak internal temperature.
Q2: What manufacturing processes create the arc shape while preserving high-temperature properties?
A2: The arc shape is achieved through wire electrical discharge machining (EDM) or diamond grinding. These precision methods ensure a smooth finish that protects the coating integrity. High-temperature grades (SH, UH, EH, AH) are typically processed from sintered NdFeB blocks by wire cutting. Premium manufacturers maintain tight tolerances of 0.02mm on arc geometry to minimize air gaps and maximize motor efficiency.
Q3: Where are high-temperature arc neodymium magnets most commonly applied?
A3: They are essential for EV motors, industrial drives, high-speed BLDC motors, generators, and magnetic couplings where both strong magnetic output and elevated temperature tolerance are required. The arc shape matches rotor/stator contours to minimize flux leakage. Specific uses include voice coil motors (VCMs), coreless DC motors, and aerospace actuators operating at high thermal limits.
Q4: How do you select the right high-temperature arc magnet grade for a motor application?
A4: First, determine your motor's maximum operating temperature including safety margin. For 120°C environments, choose H‑grade; for 150°C, SH‑grade; for 180°C, UH‑grade; for 200°C+, EH or AH‑grade. Also consider coercivity – higher grades (SH/UH/EH) have greater intrinsic coercivity to resist demagnetization under thermal stress. Always specify the grade with a suffix; otherwise, you'll receive standard 80°C magnets.
Q5: What coatings are recommended for high-temperature arc neodymium magnets?
A5: Nickel‑copper‑nickel (NiCuNi) is the standard coating, offering corrosion resistance up to 200°C. For more demanding environments, epoxy coatings provide additional chemical protection. Zinc plating is cost‑effective but thinner. The coating must withstand thermal expansion without cracking – nickel performs well up to 220°C. For specialty applications, gold, silver, or PTFE coatings are available. Always verify that the coating's temperature rating matches the magnet grade.