Yong Magnet (permanent parochial), permanent magnets, can be natural products, also known as natural magnets, or can be manufactured by artificial (the most powerful magnet is NdFeB magnets). With wide hysteresis loop, high coercivity, high residual magnetism, the material which can maintain constant magnetism once magnetized. Also known as permanent magnet materials, hard magnetic materials. In the application, the permanent magnet works in the demagnetization part of the second quadrant of the magnetic Rayleigh back line after deep magnetic saturation and magnetizing. The permanent magnet shall have the highest possible coercive force HC, residual magnetism BR and maximum magnetic energy product (BH) m to ensure maximum magnetic energy and stable magnetism.