Applied Physics and Materials Science

Magnetism and Magnetic Matterials

Magnetism arises from two sources 1) Electric Current and 2) Spin Magnetic moments of elementary particles. Mostly effects of magnetism are seen in Ferromagnetic materials, which are strongly attracted by magnetic fields and which can become permanent magnet in a long exposition by magnetization. Iron, nickel, cobalt and their alloys are most commonly known ferromagnetic materials. Lodestone, a form of natural iron ore called magnetite is the first material in which permanent magnetism was found. There are many types of magnetic materials such as paramagnetic substances, diamagnetic substances and antiferromagnetic substances. But the force of these materials is too weak and can only be detected by laboratory instruments. The magnetic state depends on temperature, pressure and the applied magnetic field.