Question

What are hard magnetic materials?

Answer 1

Magnetic materials

1. A material is said to be magnetic if a magnetic field is created around it. Magnetic materials can be made to become magnetized either spontaneously or intentionally by exposing them to an external magnetic field.
2. When a substance is held in a magnetic field, magnetic dipole moments start to build inside of it, magnetizing the substance.
3. The material becomes magnetized when these dipole moments line up in the same direction as the external magnetic field.

Hard magnetic materials

1. Hard magnetic materials are highly challenging to magnetize, once they are, they become powerful, long-lasting magnets. Both their retentivity and coercive force are very high in these materials. The region beneath the hysteresis loop is nearly rectangular and stands fairly tall.
2. The initial permeability of hard magnetic materials is modest, and they have a large hysteresis loop.
3. Therefore, hard magnetic materials are those which can get permanently magnetized.
4. Example: Nickel, Neodymium, etc.