Magnetic inclusion

For the case of electro-magnets, inclusions detection in welds situated at 1-2 mm of depth is very important, because the reluctance variation between the two mediums is not important, and thus the detection of this type of defect is very difficult. It will be sufficient to be in optimal conditions to eliminate this problem. 

Relevant Magnetic Potential Parameters Calculation of the Static Magnetization Inclusion of Thermal Agitation A. Langevin s Treatment of Brownian Motion ... 

Nuclear fusion energy is the great hope for the future, and tremendous efforts were and are being spent to demonstrate and to achieve breakeven for this type of energy, especially for the magnetic inclusion of the high-temperature plasma... 

The Zond VD - 96 is intended for the detection of cracks, precipitates, inclusions etc. and corrosive defects with the preliminary estimation of their depth in various objects of magnetic and non - magnetic steels, non-ferrous and refractory metals and welds including coatings. 

The aim of the work we present in this paper is to optimize the control parameters used in particles magnetic and interpret the obtained results. Experiments are performed on samples of welds or materials containing known defects. The realized and tested defects are grooves situated at different depths with variables dimensions. Other types of defects have been studied (inclusions, lack of penetration, etc.). 

Detection of Ferrous Inclusions in Non-magnetic Turbine Disks... 

An important application of the HMT is the test for ferrous inclusions in high pressure turbine disks made from a non-magnetic metal alloy. On principle, such ferrous inclusions can be introduced during the manufacturing process and, if present, they can be the origin of cracks in these most critical parts. Therefore such tests are stringent necessary. 

A measurement procedure has been developed that allows to determine the mass of the inclusions as well as their locations with respect to radius, angle, and depth (2). For the depth determination use is made of the approximate 1/R dependence of the magnetic field strength from the distance R to the inclusion When in a first measurement at a small lift off an inclusion is detected, the measurement is repeated at an increased lift off From the signal ratio the depth can be calculated or seen from a diagram like fig. 5a which was generated experimentally. After that, from calibration curves like fig. 5b the absolute value of the signal leads to the mass of the inclusion. 

The first application has been fully developed and is performed in a routine service Turbine disks are tested for extremely small iron inclusions. The physical principal is to measure their magnetic remanence. 

The higher-order bulk contribution to the nonlmear response arises, as just mentioned, from a spatially nonlocal response in which the induced nonlinear polarization does not depend solely on the value of the fiindamental electric field at the same point. To leading order, we may represent these non-local tenns as bemg proportional to a nonlinear response incorporating a first spatial derivative of the fiindamental electric field. Such tenns conespond in the microscopic theory to the inclusion of electric-quadnipole and magnetic-dipole contributions. The fonn of these bulk contributions may be derived on the basis of synnnetry considerations. As an example of a frequently encountered situation, we indicate here the non-local polarization for SFIG in a cubic material excited by a plane wave (co) ... 

A more recent implementation, which completely eliminates the gauge dependence, is to make the basis functions explicitly dependent on the magnetic field by inclusion of a complex phase factor refening to the position of the basis function (usually the nucleus). 

The first attempts to rationalize the magnetic properties of rare earth compounds date back to Hund [10], who analysed the magnetic moment observed at room temperature in the framework of the old quantum theory, finding a remarkable agreement with predictions, except for Eu3+ and Sm3+ compounds. The inclusion by Laporte [11] of the contribution of excited multiplets for these ions did not provide the correct estimate of the magnetic properties at room temperature, and it was not until Van Vleck [12] introduced second-order effects that agreement could be obtained also for these two ions. 

Figure 1.4 Plot of the lowest hyperfine split pseudo-doublet for field applied along the easy magnetization axis of Na9Ho(W5018)2 t)H20. Grey dotted lines are obtained in the assumption of purely axial symmetry while black continuous lines result after inclusion...

Variable-temperature ESR studies have revealed large magnetic bistabilities in thiadiazole-fused 1,3,2-dithiazolyl 32 <2001SM1767, 2001MI451, 2002MI064434>, the thiadiazolopyrazine-fused 1,3,2-dithiazolyl 34, but not with the benzothiadiazolo-fused 1,3,2-dithiazolyl 33 <2004JA8256>. ESR studies have also been performed on inclusion crystals of the bicyclic [ 1,2,5]thiadiazolo[3,4-z/][ 1,3,2]dithiazol-2-yl 32 in channels of perhydrotriphenylene and tris(o-phenylenedioxy)cyclotriphosphazene <2002MI432>. 

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