How does a ferrite magnet work and how is it different from other magnets?

Working Principle of Ferrite Magnets
The main component of ferrite magnets is a composite of iron oxide (Fe₂O₃) and other metal oxides (such as strontium, barium, etc.). Its magnetism comes from its crystal structure and the arrangement of internal magnetic domains. Ferrite magnets belong to hard magnetic materials, and their crystal structure is hexagonal. In this structure, iron ions and oxygen ions form a special arrangement, which enables the material to form stable magnetic domains (i.e. microscopic magnetic regions) under the action of an external magnetic field. These magnetic domains gradually align during the magnetization process, resulting in strong magnetism.
Ferrite magnets need to undergo high-temperature sintering and magnetic field treatment during the manufacturing process. At high temperatures, the crystal structure of the material is stabilized, and under the action of an external strong magnetic field, the magnetic domains are aligned along the direction of the magnetic field to form permanent magnetism. Even if the external magnetic field disappears, the magnetic domains can still remain aligned, giving the material lasting magnetism. The magnetism of ferrite mainly comes from the arrangement of electron spins inside it. Since ferrite is a ferromagnetic material, the unpaired electron spins inside it will generate magnetic moments, which align under the action of an external magnetic field to form macroscopic magnetism.

Differences between ferrite magnets and other magnets
Ferrite magnets differ significantly from other common magnets (such as NdFeB magnets, AlNiCo magnets, and SmCo magnets) in terms of material composition, performance characteristics, and application areas.
Ferrite magnets are mainly composed of iron oxide and strontium/barium oxide, and do not contain rare earth elements. In contrast, NdFeB magnets are composed of rare earth elements neodymium, iron, and boron, with a high rare earth content; AlNiCo magnets are composed of aluminum, nickel, cobalt, and iron, without rare earth elements; and SmCo magnets are composed of rare earth elements samarium and cobalt, with a high rare earth content. This difference in composition directly affects their magnetic properties and application scenarios.
In terms of magnetic properties, ferrite magnets have a lower magnetic energy product (usually 3.5-5 MGOe), a higher coercive force, good anti-demagnetization properties, but weak magnetic force. NdFeB magnets have extremely high magnetic energy (up to 50 MGOe or more), strong magnetic force, but low coercive force and easy demagnetization. Alnico magnets have a medium magnetic energy product (5-10 MGOe), good temperature stability, but low coercivity. Smco magnets have a high magnetic energy product (20-30 MGOe), excellent temperature stability, but high cost.
Temperature stability is a major advantage of ferrite magnets. It can work in the range of -40℃ to +250℃, suitable for high temperature environments. NdFeB magnets have poor temperature stability and are easily demagnetized at high temperatures. They usually need to add elements such as dysprosium to improve temperature resistance. Alnico magnets have excellent temperature stability and can work for a long time in high temperature environments. Smco magnets have the best temperature stability and are suitable for extreme high temperature environments.
Cost and environmental protection are also important advantages of ferrite magnets. It has low cost, abundant raw materials, does not contain rare earth elements, and has good environmental protection. In contrast, NdFeB magnets have high costs, rely on rare earth resources, and have poor environmental protection; Alnico magnets have medium costs, do not contain rare earth elements, but cobalt resources are limited; Smco magnets have extremely high costs, rely on rare earth resources, and have poor environmental protection.
In terms of application areas, ferrite magnets are widely used in low-cost, high-volume scenarios such as speakers, motors, sensors, and household appliances. NdFeB magnets are mainly used in high-performance motors, hard disk drives, wind turbines, and other fields with high magnetic requirements. Alnico magnets are often used in scenarios such as instruments, sensors, and high-temperature motors. Samarium cobalt magnets are mainly used in special fields such as aerospace, military, and high-end industrial equipment.

Unique advantages of ferrite magnets
Although ferrite magnets have weak magnetic force, their unique properties give them irreplaceable advantages in many applications. Its low cost makes it an ideal choice for mass production. The raw materials are abundant and the production process is simple, making it suitable for mass manufacturing. The high coercive force of ferrite magnets makes it anti-demagnetization and suitable for long-term use. Its excellent temperature stability allows it to work stably in high temperature environments and is suitable for industrial applications. Ferrite magnets do not contain rare earth elements, are environmentally friendly, and meet modern environmental protection requirements.