Injection Molded NdFeB Magnet

Overview

Product Specifications

Key specifications include:

· Magnetic Properties: Remanence (Br): 0.7-1.05 T; Coercivity (Hcj): 750-1600 kA/m; Maximum energy product ((BH)max): 8-16 MGOe.

· Physical Properties: Density: 5.2-6.0 g/cm³; Hardness: Shore D 75-85; Tensile strength: 30-50 MPa.

· Thermal Stability: Continuous operating temperature: -40°C to 120°C (nylon binders) or 150°C (PPS binders); Curie temperature: 310-350°C.

· Geometries: Complex 3D shapes (cylindrical, annular, rectangular with cutouts, gears, flanges); Minimum wall thickness: 0.5-1.0 mm; Maximum part size: typically <100 mm (varies by mold).

Product Grades

Grades are categorized by magnetic performance and binder type:

· Standard Grades: Based on (BH)max: IM-8 (8 MGOe), IM-12 (12 MGOe), IM-16 (16 MGOe), with Hcj ranging from 800-1200 kA/m.

· High-Temperature Grades: Designated by suffix "H" (e.g., IM-12H), using PPS binders for 150°C operation; Hcj up to 1600 kA/m.

· Custom Grades: Tailored binder systems (e.g., flame-retardant, laser-markable) or magnetic powder blends for specific torque/field requirements.

Coatings

Injection-molded NdFeB has inherent corrosion resistance due to the thermoplastic binder encapsulating magnetic particles, reducing the need for additional coatings. Optional treatments for harsh environments include:

· Epoxy Coating: Thin (20-50 μm) layer for improved chemical resistance; salt spray resistance >500 hours.

· Nickel Plating: Electroless Ni-P coating for wear resistance; used in automotive underhood applications.

· Parylene Coating: Conformal coating (5-20 μm) for medical/electronics; biocompatible and moisture-proof.

Application Scope

Key applications include:

· Electronics: Micro-motors (hard disk drives, printers), camera autofocus modules, smartphone vibration motors, sensors (proximity, speed).

· Automotive: ABS sensors, fuel injector actuators, HVAC flaps, window lift motors, dashboard displays.

· Consumer Goods: Power tools (drills, screwdrivers), home appliances (refrigerator compressors, air conditioners), toys (remote-controlled vehicles), magnetic closures.

· Medical Devices: Hearing aids, insulin pumps, surgical robotics, miniature pumps.

· Industrial: Linear actuators, encoders, magnetic couplings, small gear motors.

Packaging Information

· Primary Packaging: Anti-static plastic trays or blister packs with dividers to prevent scratching and part-to-part contact; critical for maintaining dimensional precision.

· Secondary Packaging: Sealed polyethylene bags with desiccants (to control moisture) and vacuum-sealed options for long-term storage.

· Shipping Packaging: Corrugated cardboard boxes with foam inserts or molded pulp trays; labeled with grade, binder type, magnetization pattern, quantity, and handling instructions ("Avoid Static Discharge").

· Magnetic Shielding: Rarely required due to lower flux density, but available (steel sheets) for air transport compliance with IATA regulations.

Common Questions

· Multi-Pole Magnetization: Can they be magnetized with complex pole patterns? Yes, ideal for ring or arc magnets with 4-32 poles (e.g., brushless DC motor rotors).

· Design Limitations: What geometries are challenging? Very thick sections (>20 mm) may cause binder-powder separation; sharp corners require radii >0.2 mm.

· Recyclability: Are they recyclable? Yes, magnetic powder can be recovered via thermal decomposition of binders, then reprocessed into new magnets.

· Cost vs. Sintered NdFeB: Why choose injection-molded? Lower tooling costs for high volumes (>100k parts), no secondary machining, and integrated features reduce assembly steps.

Environmental Resistance: How do they perform in humidity? Nylon binders absorb moisture (up to 2% weight gain), so PPS or coated grades are recommended for humid (>85% RH) environments.