Definition
Otherwise known as "hard magnetic materials". A material that maintains a constant magnetism once magnetized. It has wide hysteresis loop, high coercivity and high remanence.
Characteristic
1.It needs a strong external magnetic field to magnetizes.
2.When the external magnetic field is deleted, the magnetic field should not disappear.
A material that maintains a perpetual magnetism once magnetized. It has wide hysteresis loop, high coercivity and high remanence.
Materials with wide hysteresis loops, high coercivity and high remanence can maintain constant magnetism once magnetized. Also called hard magnetic materials. In practice, permanent magnetic material work in the second quadrant demagnetization part of deep magnetic saturation and hysteresis loop after magnetization. Common permanent magnetic materials are Al-Ni-Co permanent magnet alloy, Fe-Cr-Co permanent magnet alloy, permanent ferrite, rare earth permanent magnetic material and composite permanent magnetic material.
Type
Permanent magnetic material includes ferrite permanent magnet, rare earth permanent magnet (rare earth cobalt, neodymium iron boron, etc.), aluminium nickel cobalt, iron chromium cobalt, aluminium iron and other materials, among which the most commonly used and used are ferrite permanent magnet and neodymium iron boron rare earth permanent magnet.
In permanent magnetic material, ferrite permanent magnet has low comprehensive magnetic properties, but compared with metal permanent magnet, it has high resistivity, good stability, strong resistance to environmental changes, abundant raw materials, high-performance and price, mature technology, and no oxidation problem. Therefore, it has a lot of applications in permanent magnetic material. Domain is still the preferred permanent magnetic material. Ferrite permanent magnet has been developing rapidly since mass production. It is anticipated that it will remain the most widely used and demanded permanent magnetic material for a long time to come.
At the same time, ferrite permanent magnet and its application products are typical products of energy saving, material savings, foreign exchange savings and export earnings. Whether from the point of view of resource utilization, or from the point of view of energy and application, its development prospects are expected to be very broad. The development of ferrite permanent magnets is of great significance to the development of China's automobile, motorcycle, electronic information and other pillar industries of the national economy and export earning foreign exchange. It is consistent with the national industrial policy and planning. With the rapid development of automated information technology, the market demand for high performance ferrite permanent magnets is growing at home and abroad. Therefore, it is necessary and promising to research, develop and produce high performance permanent magnetic material of ferrite.
