Ferromagnetism

Ferromagnetism , property of some materials that causes them to be intensely magnetized when placed in a magnetic field, and retain part of their magnetization when that field disappears.

Summary

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• 1 Explanation
• 2 Ferromagnetic materials
• 3 Materials and their temperature
• 4 See also
• 5 Sources
• 6 External links

Explanation

Ferromagnetism is a physical phenomenon in which magnetic ordering of all the magnetic moments in a sample occurs, in the same direction and direction. A ferromagnetic material is one that can show ferromagnetism. Ferromagnetic interaction is the magnetic interaction that makes magnetic moments tend to be arranged in the same direction and direction. It has to spread throughout a solid to achieve ferromagnetism.

Ferromagnets are generally divided into magnetic domains, separated by surfaces known as Bloch walls. In each of these domains, all the magnetic moments are aligned. At the boundaries between domains there is some potential energy, but the formation of domains is offset by the gain in entropy.

By subjecting a ferromagnetic material to an intense magnetic field, the domains tend to align with it, so that those domains in which the dipoles are oriented in the same direction and direction as the inducing magnetic field increase in size. This increase in size is explained by the characteristics of the Bloch walls, which advance towards the domains whose direction of the dipoles does not coincide; giving rise to a monodomain. By deleting the field, the domain remains for a certain time.

Ferromagnetic materials

There are many crystalline materials that exhibit ferromagnetism. A representative selection of them is shown in the table (Kittel, p. 449), along with their Curie temperatures, the temperature above which they are no longer ferromagnetic. Like iron , nickel , cobalt , steel, etc.

Materials and their temperature