coercivities

Coercivity is a property of ferromagnetic materials that describes their resistance to demagnetization. When a magnetic field is applied to a ferromagnetic material, it becomes magnetized. If this external field is then removed, some residual magnetization remains. Coercivity quantifies the strength of the reverse magnetic field required to reduce the magnetization of the material to zero. A material with high coercivity is difficult to demagnetize and is therefore considered a "hard" magnetic material. Conversely, a material with low coercivity is easily demagnetized and is classified as a "soft" magnetic material. The unit of coercivity is the ampere per meter (A/m) in the International System of Units (SI), or the oersted (Oe) in the CGS system. Coercivity is a crucial parameter in the design of permanent magnets, magnetic storage media, and transformers, influencing their performance and stability. The value of coercivity depends on factors such as the material's composition, microstructure, and temperature.