The key difference between magnetization and demagnetization is that magnetization is the change of magnetic moment of a magnetic per unit volume, whereas demagnetization is the removal of the magnetic property of the magnet.
Magnetization and demagnetization are discussed mainly in classical electromagnetism. These are opposite terms of each other.
CONTENTS
1. Overview and Key Difference
2. What is Magnetization
3. What is Demagnetization
4. Magnetization vs Demagnetization in Tabular Form
5. Summary – Magnetization vs Demagnetization
What is Magnetization?
Magnetization is the vector field expressing the density of permanent/induced magnetic dipole moments regarding a magnetic material. This term is used in classical electromagnetism. The movement of the material within this field can be described using the direction, and this direction is usually either axial or diametric. Moreover, the foundation of magnetic moments that determines magnetization is either microscopic electric currents, which result from the motion of electrons inside the atoms, or the spin of the electrons or the nuclei.
Net magnetization is the result of the response a material has toward the external magnetic field. When considering the magnetization of paramagnetic materials, they have a weak induced magnetization in a magnetic field. This can disappear upon the removal of the magnetic field. But in the case of ferromagnetic materials, they have strong magnetization. Moreover, the magnetization of ferromagnetic materials can make them have magnetization in the absence of an external field.
Furthermore, magnetization describes the response of a material to a magnetic field that is applied to it, along with the material’s ability to change the magnetic field. Therefore, we can use this to calculate the forces resulting from the interactions. We can compare it with the electric polarization that is indicated as the measure of the response of a particular material towards an electric field in electrostatics.
What is Demagnetization?
Demagnetization is the creation of a magnetic field by the magnetization in a magnet. This state can be defined as the alignment of domains which has been subdivided into smaller domains having random directions of magnetization. The process of demagnetization is also known as magnetic cleaning, degaussing, etc., which refers to the returning of a magnetic to a neutral state. We can achieve this state with the use of an alternating magnetic field for the removal of evenly aligned elementary magnets into a homogenous disorder.
A magnet forms upon the orientation of magnetic dipoles in a material in the same general direction. For example, we can make iron and manganese magnets by aligning the magnetic dipoles in the metal. The demagnetization process can randomize magnetic dipole orientation. This process also includes heating past the Curie point, which is done by applying a strong magnetic field, an alternating current, or hammering the metal.
Over time, demagnetization can occur naturally. The speed of this process usually depends on the material, the temperature, and some other factors. Moreover, this can occur by accident as well. However, it is typically performed intentionally upon the magnetization of parts of metals and when there is a requirement to destroy magnetic-encoded data.
What is the Difference Between Magnetization and Demagnetization?
The key difference between magnetization and demagnetization is that magnetization is the change of magnetic moment of a magnetic per unit volume, whereas demagnetization is the removal of the magnetic property of the magnet.
Below is a summary of the difference between magnetization and demagnetization in tabular form for side-by-side comparison.
Summary – Magnetization vs Demagnetization
Magnetization is the vector field expressing the density of permanent/induced magnetic dipole moments regarding a magnetic material. Demagnetization is the creation of a magnetic field by the magnetization in a magnet. The key difference between magnetization and demagnetization is that magnetization is the change of magnetic moment of a magnetic per unit volume, whereas demagnetization is the removal of the magnetic property of the magnet.
Reference:
1. Helmenstine, Anne Marie. “How to Demagnetize a Magnet.” ThoughtCo, Aug. 28, 2020.
Image Courtesy:
1. “Magnetic field lines with compass needles” By Dayna Mason (CC BY-NC-SA 2.0) via Flickr