Permeability, magnetic

The intensity of the magnetic field produced by eddy current is depended on electrical conductivity and magnetic permeability of the studied area. In case of a uniform structure, when the conductivity of the material is high, the intensity of the induced magnetic field is big and signal received by probe Hp is small. 

As for the cemented coating constitution, the carbon stability in iron is very low. This addition element is essentially present under the form of cementite. The presence of carbon atoms in iron leads to an increasing of the resistivity and diminishes the magnetic permeability. 

A magnetic probe should be realized in a material of a high magnetic permeability and a low electric conductivity. 

The eddy current method allows to evalute the state of stress in ferromagnetic material. The given method is used for determining own stress as well as that formed in effect of outside load. With regard to physical principles of own stress analysis, the dependence between the magnetic permeability and the distance between atomic surfaces is utilized. 

In effect of loads acting in the scope of elastic deformations (proportional) in polycristalline bodies, changes in distances between atomic surfaces of the net are observed, which change the initial magnetic permeability. 

At the separation surface of two mediums of different magnetic permeability, lines force trajectory is deviated by the anomaly according to known and precise laws. 

The magnetic field distribution near the surface of z = 0 separation is considered. The pattern has Ll = 0 magnetic permeability, over the pattern medium is 4 = 1. The equations for (p... 

Electrical and Magnetic Resistivity Dielectric constant Magnetic permeability... 

A separate study was the improvement of magnetic permeability in soft alloys such as are used in transformers and motors by lining up the orientations of individual crystal grains, also known as a preferred orientation this became an important subspeciality in the design of transformer laminations made of dilute Fe-Si alloys, introduced more than 100 years ago and still widely used. 

Figure 2-68 illustrates the basics of a transformer. First there is a core, usually constructed of a material of high magnetic permeability to achieve a high magnetic flux density. The core has two windings of conductors, a primary coil (designated as... 

If now the physical properties of the body (e.g., thermal expansion, compressibility, refractive index, electric and thermal conductivities, dielectric constant, and magnetic permeability) are measured along OPi, OP2, OP,. .. we find that all the bodies fall into one or other of two large groups —... 

Hashin, Z Shtrikman, S, A Variational Approach to the Theory of Effective Magnetic Permeability of Multiphase Materials, Journal of Applied Physics 33, 3125, 1962. 

In the inductive mode the magnetic permeability of a solution-containing cell placed in the field of an inductance coil represents the measuring principle of the method however, this property is not very sensitive to differences in solution composition, so that the inductive mode still remains of limited applicability. 

Here /j,0 is the magnetic permeability. When the two spheres are aligned in the direction of the external magnetic field and touch each other, cj) is given by... 

Two outstanding properties of FeB metallic glasses are their low magnetic permeabilities and their low acoustic attenuations. The former results from their lack of magnetic anisotropy and has led to their use in power transformers, theft detectors, and various electronic devices. The latter results from the very low dislocation mobility in them. 

Chemical reagents are primarily concerned with dielectric liquids or solids. For metal oxides such as ferrites, however, magnetic losses occur in the microwave region. As for a dielectric material, a complex magnetic permeability is defined as given by Eq. (16) ... 

The real part is the magnetic permeability whereas the imaginary part is the magnetic loss. These losses are quite different from hysteresis or eddy current losses, because they are induced by domain wall and electron-spin resonance. These materials should be placed at position of magnetic field maxima for optimum absorption of microwave energy. For transition metal oxides such as iron, nickel, and cobalt magnetic losses are high. These powders can, therefore, be used as lossy impurities or additives to induce losses within solids for which dielectric loss is too small. 

For absorbers with magnetic dipole transitions, the evanescent magnetic field H leads to absorption of electromagnetic energy. Assuming equal magnetic permeabilities at both sides of the interface, the components of the evanescent field H at z = 0 are... 

In Chapter 4 we will consider the so-called classical approximation, in which the electromagnetic radiation is considered as a classical electromagnetic wave and the solid is described as a continnous medium, characterized by its relative dielectric constant e or its magnetic permeability fx. The interaction will then be described by the classical oscillator (the Lorentz oscillator). 

Vacuum magnetic permeability 245 Vacuum permittivity 31 Variable field NMR relaxometry 406 Volclay 306, 308-9... 

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