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Why are iron, cobalt, and nickel strongly attracted to magnets?

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Learn about magnetic fields and the levels of particles, atoms, crystals, and domains — magnet Magnetic fields and the levels of magnetism of particles, atoms, crystals, and domains.

Iron, cobalt, and nickel are strongly attracted to magnets because they are ferromagnetic materials. This phenomenon arises from the specific behavior of their electrons and the resulting atomic structure.12

At the atomic level, electrons possess a magnetic moment due to their motion and spin. In ferromagnetic elements, a quantum mechanical effect known as the exchange interaction encourages the spins of electrons in neighboring atoms to align parallel to one another. This alignment is a lower-energy configuration that minimizes the repulsive forces between electrons, as dictated by the Pauli exclusion principle.123

These aligned atoms form small regions called domains, where all atomic magnetic moments point in the same direction. When an external magnetic field is applied, these domains rotate or grow to align with the field, resulting in strong magnetization. This collective, spontaneous alignment is what gives iron, cobalt, and nickel their characteristic magnetic strength.143