Magnetism is the result of attraction, when two objects come together, or repulsion, when two objects move apart. A magnet is an object that has properties of magnetism. For example, a magnet might attract another object. A magnetic field is the invisible area around a magnet where magnetism occurs. And magnetized means that an object acquired magnetic properties.

Now, some substances can be super magnetic and others can be partially magnetic. Let’s take a look at three different types of substances: Ferromagnetic, Paramagnetic, and Diamagnetic 

Magnetic Substances: Diamagnetic Substances

The substances which are weekly magnetized when placed in an external magnetic field, in a direction opposite to the applied filed are called Diamagnetic Substances.

Example: Copper, lead, gold, silver, zinc, antimony, bismuth, etc.

Properties:

  • These substances are repelled by magnet
  • Atomic orbitals of these substances are completely filled
  • It develops weak magnetization in a direction opposite to the direction of the applied magnetic field
  • As soon as the magnetizing field removed, it loses its magnetization
  • When placed in a non-uniform magnetic field, it tends to move from stronger to weaker regions of the magnetic field
  • When placed in a uniform magnetic field, it aligns itself perpendicular to the direction of magnetic field
  • Magnetic susceptibility is small negative value
  • Relative permeability is close to one and always less than 1

Magnetic permeability is slightly less compared to free space.

Magnetic Substances: Paramagnetic Substances

The substances which are weekly magnetized when placed in an external magnetic field, in the same direction of the applied field are called Paramagnetic Substances.

Example: Sodium, aluminum, calcium, manganese, platinum

Properties:

  • These substances are attracted by magnet
  • Atomic orbitals of these substances are partially filled
  • It develops weak magnetization in the direction of the applied magnetic field
  • After removing the magnetizing field, it loses its magnetization
  • When placed in a non-uniform magnetic field, it tends to move from weaker to stronger regions of the magnetic field
  • When placed in a uniform magnetic field, it aligns itself in the direction of magnetic field
  • Magnetic susceptibility is small positive value
  • Relative permeability is close to one and always greater than 1
  • Magnetic permeability is slightly more compared to free space

Magnetic Substances: Ferromagnetic Substances

The substances which are strongly magnetized when placed in an external magnetic field in the same direction to the applied field are called Ferromagnetic Substances.

Example: Iron, nickel, cobalt

Properties:

  • These are characterized by parallel alignment of magnetic dipoles
  • These substances are strongly attracted by magnet
  • It develops strong magnetization in the direction of the applied magnetic field
  • By removing magnetizing filed, it does not lose its magnetization
  • When placed in a non-uniform magnetic field, it tends to move from weaker to stronger regions of the magnetic field
  • When placed in a uniform magnetic field, it aligns itself parallel to the direction of magnetic field
  • Magnetic susceptibility is much greater than 1
  • Relative permeability is much greater than 1
  • Magnetic permeability is much larger compared to free space.
MaterialMagnetic Susceptibility (X)Relative Permeability
(K= 1 + Xm)
Magnetic Permeability
(μm = Kmμ0)
Diamagnetic-10-5 to -10-9< 1μm < Î¼0
Paramagnetic10-5 to 10-3> 1μm > Î¼0
Ferromagnetic≫ 1≫ 1μ Î¼0

Curie Temperature

It is the temperature above which ferromagnetic materials lose their permanent magnetic field and the magnetism completely disappears.

The magnetic susceptibility decreases with increase of temperature. So, the Ferromagnetism decreases with rise of temperature. It is maximum at absolute zero temperature and becomes zero at Curie temperature. Above this temperature the ferromagnetic material behaves as Paramagnetic substance.

Hope this article on Magnetic Substances was helpful for you. If you have any doubts/queries regarding the same you can let us know in the comment section below!