In material science, the Coercivity of a ferromagnetic material is the intensity of the magnetic field required to reduce the magnetization of that material to zero after the magnetization of the sample has reached saturation. A ferromagnet is a piece of ferromagnetic material, in which the microscopic magnetized regions, called domains, have been aligned by an external magnetic field (e. ... Current flowing through a wire produces a magnetic field (M) around the wire. ... For magnetic materials, saturation is the state when the material can not absorb a stronger magnetic field, such that an increase of magnetization produces no significant change in magnetic flux density. ...