Ferrite Disc Magnet

About Ferrite Disc Magnet

An 8x3 ferrite disc magnet is a cylindrical permanent magnet with a diameter of 8 mm and a thickness (height) of 3 mm, made from ferrite ceramic material, typically barium ferrite (BaFeO) or strontium ferrite (SrFeO). These magnets are widely used for their cost-effectiveness, chemical stability, and moderate magnetic strength in industrial, electronic, and consumer applications.

Material and Composition

The 8x3 ferrite disc magnet is a hard ceramic magnet produced by powder sintering. Its main components include:

1. Iron Oxide (FeO) ~7075% by weight, forms the magnetic ferrite lattice and provides the fundamental magnetic properties.

2. Strontium Carbonate (SrCO) or Barium Carbonate (BaCO) ~2530% by weight, stabilizes the crystal structure and enables permanent magnetism.

3. Minor additives (02%) such as TiO or CoO, may be added to improve sintering, surface quality, or mechanical strength.

The powders are pressed into the disc shape and sintered at high temperatures (~12001300C) to produce a dense, hard, and brittle magnetic ceramic. The surface is typically matte or semi-smooth, and the disc may be coated or painted for corrosion protection, though ferrite is naturally resistant to most chemicals.

Key Characteristics

• Permanent Magnetism: Retains magnetization without an external power source.

• Magnetic Strength: Moderate, suitable for holding, sensing, or low-cost magnetic assemblies.

• Brittleness: Hard but brittle; prone to chipping or cracking under mechanical impact.

• Chemical Resistance: Excellent resistance to corrosion, moisture, oils, and most acids or alkalis.

• Electrical Insulation: Non-conductive, safe for use in electronic assemblies.

• Temperature Stability: Operates effectively up to ~250C without significant loss of magnetic performance.