Will the magnet's magnetism disappear? The answer is yes, the magnet is not permanent. The external factor will change its magnetism, such as more than its high temperature will make it lose magnetic, the impact will make it lose magnetic, powerful magnetic field can change its magnetic pole and magnetic strength. The magnetic field produced by the alternating current of the size change will soon demagnetize the magnetic object. In the absence of external factors to add the magnetic field is the magnet can maintain its own magnetic objects. Permanent magnets can be made of ferromagnetic materials such as iron and nickel. Its atomic structure is special, the atom itself has a magnetic moment. Metal, iron, cobalt, nickel is the most common on the market is also commonly used magnet, magnets can be divided into permanent magnetic and soft iron, permanent magnet is coupled with a strong magnetic So that the magnetic material spin and the electronic angular momentum into a fixed direction; soft magnetic is coupled with the current, if there is no current, soft iron is lost magnetic. Magnet is a generic term for all types of magnets, and is generally referred to as having magnetic properties. The actual composition does not necessarily contain iron. Relatively pure metal state of the iron itself is not permanent magnetic, only close to the permanent magnet will be induced and produce magnetic, the general permanent magnet which added other impurity elements, such as carbon will make the magnetic stability down, but this will make the electronic Reduced freedom and easy to conduct. So when the current through the light when the bulb is not bright, is posted with a common magnetic elements, but many elements are more powerful magnetic, such as the strength is mixed with NdFeB magnets.