Difference Between Hard and Soft Magnetic Materials

Hard vs Soft Magnetic Materials
 

Magnetic materials are very important in the industries related to magnetism. Magnetic induction is the conversion of a magnetic material into a magnet. Hard and soft magnetic materials are used in such magnetization processes. The concept of magnetization plays a very important role in fields such as electromagnetic theory and magnetism. It is vital to have a proper understanding in the concept of magnetization and magnetic materials. In this article, we are going to discuss magnetism, magnetic induction, and what soft magnetic materials and hard magnetic materials are, their applications, similarities, and finally the difference between soft magnetic material and hard magnetic material.

What is Soft Magnetic Material?

In order to understand the concept of soft magnetic materials, one must first have a background knowledge in magnetic induction. Magnetic induction is the process of magnetization of materials in an external magnetic field. Materials can be categorized into several according to their magnetic properties. Paramagnetic materials, Diamagnetic materials and Ferromagnetic materials are to name a few. There are also some lesser common types such as anti-ferromagnetic materials and ferrimagnetic materials. Diamagnetism is shown in atoms with only paired electrons. The total spins of these atoms are zero. The magnetic properties arise only due to the orbital motion of electrons. When a diamagnetic material is placed in an external magnetic field, it will produce a very weak magnetic field antiparallel to the external field. Paramagnetic materials have atoms with unpaired electrons. The electronic spins of these unpaired electrons act as small magnets, which are very stronger than the magnets created by the electron orbital motion. When placed in an external magnetic field, these small magnets align with the field to produce a magnetic field, which is parallel to the external field. Ferromagnetic materials are also paramagnetic materials with zones of magnetic dipoles in one direction, even prior to the external magnetic field is applied. When the external field is applied, these magnetic zones will align themselves parallel to the field so that they would make the field stronger. Ferromagnetism is left in the material even after the external field is removed, but paramagnetism and diamagnetism vanishes as soon as the external field is removed. The soft magnetic materials are a part of the ferromagnetic material family. The soft magnetic materials show strong magnetic properties in an external magnetic field but lose the magnetism after the external field is removed. This causes a leaf like hysteresis curve.

What is Hard Magnetic Material?

Hard magnetic materials have more powerful magnetization than the soft magnetic materials when exposed to an external field. Hard magnetic materials will contain the magnetism even after the external field is removed. These are used to create permanent magnets. The hysteresis loop of the hard magnetic materials is almost a square shaped one.