- May 21, 2019-

1, Atomic structure

The magnetism of material  is come from electronic in the atoms of material. Material is made of atoms, and atoms is made up of nuclei and electronic, which is located in the nucleus. Nucleus is similiar to the sun, and the extranuclear electron just like a planet going round the Sun. Besides electronic spin, it can run around  the electronic nucleus.

In addition, the electron will be layered if a number of atoms extranuclear electron, each layer has a different number of electrons. The first layer is 1 s, and the second floor has two layer 2 p and 2 s, and the third layer has three layer 3 s, 3 p and 3 d, and so on.


Magnetic field inside the atom

Extranuclear electron is a charged particles with negative charge in atomic. Electronics is a small magnets with N pole and S pole because the Electronic spin. In other words, electronic like many small magnet run around the nucleus in the rotation. In fact, it’s similiar to the suituation of creating a magnetic field by electronic.

The atomic magnetic is come from the magnetic moment of the electrons and nuclei of atoms.Nuclear magnetic moment is small, and it can be ignored in the problems that we consider.
Electronic magnetic moment (orbital magnetic moment, the spin magnetic moment)
The total magnetic moment of the atom.


3.Why most substances without strong magnetic

Generally speaking, there are two kinds of electronic’s rotation direction. That is up and down. In some material, the magnetic pole they produce will offset each other because the same number of electronic spin up and down. So the whole atom of entire object show any magnetic . For the most situation that different rotation direction in different munber of electronic, these electronic magnetic moment cannot cancel each other out, causing the atom has a certain total magnetic moment. But there is no interaction between magnetic moment these atoms, they are confused and the whole object without strong magnetic.

4.Methods for making magnets

Heating permqanent magnet can make it magnetic disappear. A phenomenon first noticed by the French scientist Pierre Curie (1859 ~ 1906),that is the magnetic will completely disappear when the magnet in a particular temperature, and the magnet won’t recover after cooling down. The temperature value is according to his name, called “Curie temperature. The temperature of magnet is depends on the composition.