Why Magnets Attract Metals

Why Magnets Attract Metals

Magnets attract metals because of the behavior of electrons within the metal's atoms. Most metals, like iron, cobalt, and nickel, have unpaired electrons in their outermost shells. These unpaired electrons generate tiny magnetic fields.

When a magnet is brought near a metal, the magnetic field of the magnet causes the electrons in the metal to align in a way that reinforces the magnet's field. This alignment creates a strong interaction between the metal and the magnet, causing them to attract each other.

In ferromagnetic metals (like iron), this alignment is especially pronounced, making them strongly magnetic and more likely to be attracted to magnets. The attraction occurs because of the interaction between the magnet's field and the metal's electrons, which is rooted in quantum mechanics and the magnetic properties of the material.

Which Materials Can Attract Metals

Materials are magnetic if their valence electrons align in a special way. This is most likely to happen in transition metals, since they have many loosely held valence electrons. Iron, cobalt and nickel are often magnetic. The earth's iron core makes it a giant magnet, and the terms north and south are used to describe the two directions of a magnetic field. The north pole of a magnet is attracted to the earth's North Pole.

Compounds can also be magnetic. An iron ore with the formula Fe3O4 found in Magnesia, Turkey was called magnetite, and its name because associated with the unusual property. In medieval times the rock was called lodestone (since it will "lead" north) and it was used for navigation. People discovered that iron or steel needles could be rubbed on the rock to acquire magnetization. These needles were made into navigational compasses.

Ceramic magnets such as iron, cobalt, and chromium oxides are manufactured by powder metallurgy. Small particles can be mixed with polymers to make flexible refrigerator magnets, or coated on plastic strips to make audio and video recording tapes. Strong magnetic fields are applied during processing to align the fields of the particles. Deposition of thin films in a vacuum chamber is used for computer hard drives.
Alloys can make very strong magnets. The first successful combination, aluminumnickel-cobalt, was discovered in the 1930's. Alloys containing rare earth elements are even more successful. Samarium cobalt and neodymium-iron-boron are two common combinations.
In the early 1800's it was discovered that electric current running through coils of wire creates a magnetic field. Electromagnets are used in electric transformers.
Magnetism may be lost when a material is heated. Upon heating the electrons gain energy and can reorient, losing their special alignment.

List of Magnetic Metals: Types, Properties, and Applications

Magnetic metals are materials that exhibit magnetic properties, either permanently or when exposed to an external magnetic field. These metals can be categorized into ferromagnetic, paramagnetic, and diamagnetic types, each with distinct behaviors and applications.

1. Ferromagnetic Metals (Strongly Magnetic)

These metals retain their magnetization and are strongly attracted to magnets.

• Iron (Fe) – The most common magnetic metal, used in electromagnets, transformers, and structural steel.

• Nickel (Ni) – Used in stainless steel, rechargeable batteries (NiMH), and magnetic shielding.

• Cobalt (Co) – Essential in high-performance magnets (e.g., AlNiCo, SmCo) and aerospace alloys.

• Gadolinium (Gd) – Exhibits strong ferromagnetism below 20°C, used in MRI contrast agents and data storage.

• Alloys (AlNiCo, Permalloy, Steel) – Steel (Fe + C) is widely used in motors, while AlNiCo (Al-Ni-Co-Fe) is found in sensors and guitar pickups.

2. Rare Earth Magnets (Strongest Permanent Magnets)

These are alloys containing rare earth elements, offering exceptional magnetic strength.

• Neodymium (NdFeB) – The strongest commercial magnet, used in hard drives, electric vehicles, and wind turbines.

• Samarium-Cobalt (SmCo) – High-temperature stability, used in aerospace and military applications.

3. Paramagnetic Metals (Weakly Attracted to Magnets)

These metals are only magnetic under an external field and lose magnetism when removed.

• Aluminum (Al) – Weakly paramagnetic, used in non-magnetic structural applications.

• Platinum (Pt) – Used in medical devices and fuel cells.

• Manganese (Mn) – Enhances steel strength and is used in lithium-ion batteries.

4. Diamagnetic Metals (Repelled by Magnets)

These metals generate an opposing magnetic field when exposed to a magnet.

• Copper (Cu) – Used in electrical wiring and MRI machines due to its non-magnetic properties.

• Gold (Au) & Silver (Ag) – Used in electronics and medical implants where magnetic interference must be avoided.