Ferromagnetism
From Wikipedia, the free encyclopediaFerromagnetism is the "normal" form of magnetism which most people are familiar with, as exhibited in horseshoe magnets and refrigerator magnets, for instance. It is responsible for most of the magnetic behavior encountered in everyday life. The attraction between a magnet and ferromagnetic material is "the quality of magnetism first apparent to the ancient world, and to us today," according to a classic text on ferromagnetism.[1] Ferromagnetism is defined as the phenomenon by which materials, such as iron, in an external magnetic field become magnetized and remain magnetized for a period after the material is no longer in the field. All permanent magnets are either ferromagnetic or ferrimagnetic, as are the metals that are noticeably attracted to them. Historically, the term ferromagnet was used for any material that could exhibit spontaneous magnetization: a net magnetic moment in the absence of an external magnetic field. This general definition is still in common use. More recently, however, different classes of spontaneous magnetisation have been identified when there is more than one magnetic ion per primitive cell of the material, leading to a stricter definition of "ferromagnetism" that is often used to distinguish it from ferrimagnetism. In particular, a material is "ferromagnetic" in this narrower sense only if all of its magnetic ions add a positive contribution to the net magnetization. If some of the magnetic ions subtract from the net magnetization (if they are partially anti-aligned), then the material is "ferrimagnetic". If the ions anti-align completely so as to have zero net magnetization, despite the magnetic ordering, then it is an antiferromagnet. All of these alignment effects only occur at temperatures below a certain critical temperature, called the Curie temperature (for ferromagnets and ferrimagnets) or the Néel temperature (for antiferromagnets).it is not feromagnetic
they are iron nickel cobalt and manganese
Ferromagnetism
Heating randomizes the alignment of the atoms.
Maxwell's equations ... electro-magnetism.
Cobalt, iron, and nickel exhibit ferromagnetism at reasonable temperatures. Check the Wikipedia article on "ferromagnetism", for additional materials that exhibit ferromagnetism - some of them are compounds, and some only exhibit ferromagnetism at temperatures that are too low for many practical uses (for example, Dysprosium requires a temperature below 88 kelvin).
J. R. Ashworth has written: 'Ferromagnetism' -- subject(s): Iron, Magnetism
At a specific high temperature, called Curie point, the ferromagnetism disappear.
Richard M. Bozorth has written: 'Ferromagnetism' -- subject(s): Magnetism, Magnetic materials
J. Robert Schrieffer has written: 'Electronic structure of impurities in metals' -- subject(s): Ferromagnetism, Metals, Superconductivity
A. G. Gurevich has written: 'Magnetization oscillations and waves' -- subject(s): Spin waves, Magnetostatics, Ferromagnetism, Ferrites (Magnetic materials)
Palladium is considered weakly magnetic. It exhibits a very small magnetic susceptibility. It is not considered to be a ferromagnetic material. Contaminants can, however, make Pd show ferromagnetism.