Application of Neodymium Permanent Magnet in Acoustic Industry
The application of NdFeB magnet in the field of Electroacoustics includes loudspeaker, receiver, microphone, stage sound, alarm, car sound, etc.
The situation of Acoustic Industry
With the development of digital, multi-functional and thin, light, small and portable electronic equipment, and the development of electronic information system towards networking, high-speed processing, high-speed transmission and broadband, the development of electro-acoustic devices ushered in a new growth point.
In 2018, the global market capacity of electro-acoustic devices is about 10 billion. Among them, there are 4.39 billion speakers/buzzers, 1.210 billion speakers and 800 million microphones. It is expected that the world market of electro-acoustic devices will continue to grow at an average annual rate of 10% in the next five years, reaching 14.5 billion by 2023 and more than 130 billion by sales.
Speakers are one of the electroacoustic materials. The basic material for making loudspeakers is a permanent magnet. Rare earth permanent magnet Nd-Fe-B alloy is a very good material for making loudspeakers.
The working principle of loudspeaker
The permanent magnet generates a magnetic field in the annular air gap of the magnetic circuit through the yoke iron, and the voice coil connected with the speaker paper basin is inserted into the annular air gap. The permanent magnet is surrounded by the external yoke iron, thus avoiding the interference of the external stray magnetic field. In turn, the influence of the magnetic field of the permanent magnet can be reduced. When the sound passes through the magnetic field in the form of current, the coil will change due to the strength of the current. It generates different frequencies of vibration, and then drives the paper basin to produce different frequencies and strong sounds.
Benefits of Neodymium Permanent Magnet
The use of rare earth permanent magnet NdFeB instead of traditional ferrite magnets or Al-Ni-Co magnets can not only improve the sensitivity of loudspeakers but also greatly reduce the number of magnets used.
NdFeB magnet is a kind of energy storage material, which can generate a constant magnetic field in a certain space. NdFeB magnets have been widely used in many fields, especially in high-tech fields, due to their high coercivity and magnetic energy product, especially their excellent performance in the environment of 20-150℃ compared with other permanent magnets.