Ferromagnetism¶

Ferromagnetism is a physical phenomenon in which certain electrically uncharged materials strongly attract others. In contrast to other substances, ferromagnetic materials are magnetized easily, and in strong magnetic fields the magnetization approaches a definite limit called saturation. When a field is applied and then removed, the magnetization does not return to its original value; this phenomenon is referred to as Hysteresis. When heated to a certain temperature called the Curie point, which is different for each substance, ferromagnetic materials lose their characteristic properties and cease to be magnetic; however, they become ferromagnetic again on cooling.

A ferromagnetic substance contains permanent atomic magnetic dipoles that are spontaneously oriented parallel to one another, even in the absence of an external field.

1. Ferromagnetism | Britannica