What materials are magnetic?

Materials containing varying degrees of iron (Fe) are strongly attracted to or can be drawn toward a magnetic field source. Such materials are known as ferromagnetic materials and are the metals most easily influenced by an external magnetic field. Iron-based materials have a higher number of unpaired electrons in their molecules compared to other metals. These free electrons can be aligned more readily and densely in the presence of an external magnetic field, effectively converting the ferrous material into a magnetized object, i.e., a magnet.

While iron is the most easily magnetized material, other metallic elements, such as nickel and cobalt, also exhibit significant magnetic properties. Iron and steel alloys possess magnetic characteristics, though to a lesser extent. Some magnetic alloys contain iron, while others include steel; very strong alloys may be composed of rare earth minerals like neodymium and samarium cobalt. Most common materials have a nucleus with electrons in some state. In the majority of these materials, the effect of a magnetic field on these electrons is so minimal that it is nearly imperceptible without electronic detection devices. Metal detectors utilize active electrical signals to measure the influence of a magnetic field, enabling the detection and differentiation of other metals like gold, copper, silver, and tin. Additionally, materials such as copper and aluminum exhibit unique interactions with magnetic fields that can generate an electric current.

Response to Magnets by Material Type

Superconductor: Strongly repelled (at low temperatures)
Diamagnetic: Weakly repelled
Paramagnetic: Weakly attracted (e.g., oxygen, tungsten, aluminum)
Ferromagnetic: Strongly attracted (e.g., iron, cobalt, nickel)