Magnetic properties of matter

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When placed in a magnetic field of an object, its "behavior" and the type of internal structural changes will depend on the material from which the object is made.All known materials can be divided into five main groups: paramagnetic, ferromagnetic and antiferromagnetic, ferrimagnetic and diamagnetic.In accordance with this classification distinguish magnetic properties of matter.To understand what lies behind these terms, we consider each group in more detail.

substance exhibiting the properties of paramagnetism, characterized by magnetic permeability with a positive sign, regardless of the value of the external magnetic field, which is the subject.The best known representatives of this group are oxides of nitrogen and oxygen gas, metals and alkaline earth alkaline group and ferrous salts.

high magnetic susceptibility is positive (up 1 million.) Characteristic of the ferromagnet.Being dependent on the intensity of the external field and temperature susceptibility varies widely.Importantly, because elementary particles of different points in the structure sublattices are equal, then the total value of the moment is zero.

As for the title, and on some of the properties they are close ferromagnetic material.They are united by the high dependence of the susceptibility of the heating and field strengths, but there are differences.The magnetic moments of the atoms placed in the sublattices are not equal to each other, so, unlike the previous group, the total time is different from zero.The substance is inherent in the spontaneous magnetization.Contact sublattices antiparallel.The best known ferrites.Magnetic properties of the substances in this group are high, so they are often used in engineering.

Of particular interest is a group of antiferromagnets.Upon cooling, similar substances below a certain temperature limit of the atoms and ions are arranged in a crystal lattice, naturally changing their magnetic moments, getting protivoparallelnoe orientation.An entirely different process takes place by heating the substance - he recorded the magnetic properties that are typical of the group of paramagnetic substances.Examples include carbonates, oxides, and so forth.

Finally, diamagnetic.The magnetic properties of the material of this group does not depend on the field intensity, and value of the magnetic susceptibility is negative.If the substance has a covalent bond, it is a "pure" diamagnetic.Representatives of - gold, copper, and other inert gases.

Magnetic properties of the material widely used in modern technology.For example, the windings of the transformer windings are wound on the magnetic materials.High permeability and magnetized to saturation, even in the low-intensity means a narrow hysteresis loop in the graph, as well as minor losses at magnetization reversal of that demand in electrical engineering.If the magnetic properties of the substance comply with magnetic materials, for the products made of it characterized by a significant flow, limited only by saturation.In practice, this means being able to reduce the size of the magnetic circuit, thereby reducing the weight of the device.However, the merits of lies and lack of - alternating field generated in this material eddy currents causes heating, so a compromise solution is reclaiming the conductor.

Another type of material - magnetically, the coercive force of which is not less than 4000 amperes per meter.This means that for the magnetization reversal of the magnetic field are necessary with high intensity, after which the material retains magnetic properties, becoming a permanent magnet.