Related topics: magnetic properties

A new 2-D magnet draws future devices closer

We are all familiar with the image of electrons zipping around an atom's nucleus and forming chemical bonds in molecules and materials. But what is less known is that electrons have an additional unique property: spin. It ...

Small currents for big gains in spintronics

University of Tokyo researchers have created an electronic component that demonstrates functions and abilities important to future generations of computational logic and memory devices. It is between one and two orders of ...

Direct atom-resolved imaging of magnetic materials

In conventional electron microscopes, performing atomic-resolution observations of magnetic materials is particularly difficult because high magnetic fields are inevitably exerted on samples inside the magnetic objective ...

New material with magnetic shape memory

Researchers at the Paul Scherrer Institute PSI and ETH Zurich have developed a new material that retains a given shape when it is put into a magnetic field. It is a composite material consisting of two components. Unlike ...

3-D magnetic interactions could lead to new forms of computing

A new form of magnetic interaction which pushes a formerly two-dimensional phenomenon into the third dimension could open up a host of exciting new possibilities for data storage and advanced computing, scientists say.

page 1 from 23

Magnet

A magnet (from Greek μαγνήτις λίθος magnḗtis líthos, "Magnesian stone") is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials and attracts or repels other magnets.

A permanent magnet is one made from a material that stays magnetized. An example is a magnet used to hold notes on a refrigerator door. Materials that can be magnetized, which are also the ones that are strongly attracted to a magnet, are called ferromagnetic (or ferrimagnetic). These include iron, nickel, cobalt, some rare earth metals and some of their alloys (e.g. Alnico), and some naturally occurring minerals such as lodestone.

Although ferromagnetic (and ferrimagnetic) materials are the only ones with an attraction strong enough to a magnet to be commonly considered "magnetic", all other substances respond weakly to a magnetic field, by one of several other types of magnetism.

An electromagnet is made from a coil of wire which acts as a magnet when an electric current passes through it, but stops being a magnet when the current stops. Often an electromagnet is wrapped around a core of ferromagnetic material like steel, which enhances the magnetic field produced by the coil.

The overall strength of a magnet is measured by its magnetic moment, while the local strength of the magnetism in a material is measured by its magnetization.

This text uses material from Wikipedia, licensed under CC BY-SA