magnetizable

Magnetizable describes the property of a material or object to acquire a magnetic moment when exposed to an external magnetic field. The extent to which it becomes magnetized is typically characterized by magnetic susceptibility, χ, with the magnetization M related to the applied field H by M = χH. Materials can be categorized as paramagnetic (positive, small χ), diamagnetic (negative χ), or ferromagnetic (large χ with possible permanent magnetization). Ferromagnetic materials can retain a degree of magnetization after the external field is removed, whereas paramagnetic and diamagnetic materials do not.

In chemistry, magnetizability also refers to the extent to which a molecule or ion develops an induced magnetic moment in a field; the magnetizability can be described by a tensor that relates an applied magnetic field to the induced magnetic dipole moment. This molecular perspective helps explain how different substances respond to magnetic fields at the atomic level.

Common magnetizable materials include iron, nickel, cobalt, ferrites, and many alloys. Some substances are only weakly magnetizable under typical field strengths, or are effectively non-magnetizable. The degree of magnetizability depends on factors such as electronic structure, temperature, and microstructure, with ferromagnets showing pronounced effects due to domain alignment and exchange interactions.

Applications rely on magnetizability: transformer cores, magnetic storage media, motors and actuators, sensors, and magnetic shielding. The term is closely related to magnetic susceptibility and magnetization; a material is magnetizable if it can be polarized by an external field, with the response determined by its intrinsic properties and conditions.