Ferrite magnets are metal oxides with ferromagnetism. In terms of electrical properties, the resistivity of ferrite is much higher than that of metal and alloy magnetic materials, and it also has higher dielectric properties. The magnetic properties of ferrite also exhibit high permeability at high frequencies. Therefore, ferrite has become a widely used non-metallic magnetic material in the high-frequency weak current field. It belongs to non-metallic magnetic materials and is a composite oxide (or ferrite) of magnetic iron oxide and one or more other metal oxides. Magnetic force is usually between 800 and 1000 Gauss and is often used in instruments such as speakers and speakers. [3]

The advantages of neodymium iron boron magnets are high cost-effectiveness and good mechanical properties; The disadvantage lies in the low Curie temperature point, poor temperature characteristics, and easy pulverization corrosion. It must be improved by adjusting its chemical composition and adopting surface treatment methods to meet the requirements of practical applications. Neodymium iron boron is a third-generation rare earth permanent magnet material with the characteristics of small size, light weight, and strong magnetism. It is currently the most cost-effective magnet and is known as the magnetic king in the magnetic field. The advantages of high energy density have made neodymium iron boron permanent magnet materials widely used in modern industry and electronic technology. In a bare magnetic state, the magnetic force can reach around 3500 Gauss.