Magnets are important functional materials for industrial, military, and civilian applications because they can pick up weights up to 640 times their own weight. Magnets play an important role in the conversion of electrical energy into mechanical energy, electrical energy into acoustic energy, and mechanical energy into electrical energy. Strong magnets can well meet the needs of downstream products, being thin and light, as well as energy saving. This makes the end product more comfortable, convenient, energy-saving and effective, and has a wide range of applications.