The magnetic effect of the material is of basic research. It provides rich information that is interconnected by the material structure, various interactions within the material, and the various physical properties caused by it. For example, the magnetic light effect can be used to detect the transition of magnetic electrons and its energy levels of magnetic substances; magnetic electrical effects reflect the interaction between transmission electrons and electrons that cause macro magnetic electrons. Magnetic effects have or obtained important applications in technology applications, providing various new devices, new materials and new methods for various needs. For example, magnetic-force effects and magnetic sound effects are used to manufacture electrocomputers and delay lines respectively; magnetic light effects are used to observe the distribution of magnetic intensity, develop magnetic light devices and magnetic light storage devices; The heating and degeneration is an effective means to obtain ultra -low temperature; the magnetic resistance effect is used to detect magnetic fields and make new magnetic heads and foam detectors. In terms of engineering technology, constant elastic materials and low-expansion coefficient materials are based on magnetic-force effects and magnetic thermal effects, all related to the magnetic telescopic effect.