High Frequency Magnetics

These past two to three decades have witnessed significant increases in switching frequencies. Specifically, switching frequencies have risen from the 75-kHz range to the 1000-kHz (1 MHz) range and beyond. This has facihtated the decrease of physical sizes of electronics objects, such as ICs, board areas, etc. Such trends have been more visible in the power-module arena where very low profile and minimal board area is required. 

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The application of WIROTEST 202 device with high frequency magnetic currents, will allow for simultaneous detection of parts with bums, which can occur during grinding. 

Arc Plasma Method The principle of NPs synthesis in this method is based on evaporation by heating and condensation by cooling. The bulk metal is evaporated by heating with electrical resistance, electron beam, or high-frequency magnetics, and subsequently the vapor of metal atoms is condensed on a substrate as a sohd film or particles. In the AP method, electrical charge filled in an external capacitor... 

The value of the exchange modes of the magnetic resonance has the same order of a magnitude as triplet excitations in the dimerized state [5], These modes exist in both U- and D-AFM states. Furthermore, these modes excite by a high frequency magnetic field polarized perpendicular to easy axis. Their intensities define by the DM interactions. The spin oscillations in these modes respect to a violation of 3D AFM order along chains as well as between chains. Therefore, one can expect an amplification of their intensities under motion of boundaries between coexisting SP- and AFM states. The next experiments are necessary to make situation clear. 

Replacement of active centres by a high frequency magnetic field... 

Dispersion of magnetic suspensions may be effected by subjecting the suspension to a high frequency magnetic field [109]. For the Autometrics PSM 200, 400 Hz was selected at a peak field strength of 800 Oersted [110]. 

Ohnuma S (1996) High-frequency magnetic properties in metal-nonmetal granular films. JApplPhys 79 5130-5135... 

High-frequency magnetic fields cause eddy currents to flow in conductive materials, or composites containing conductive fibers or a certain amount of graphite. Mainly limited to... 

Limited at first to the inspection of metallic components, it was later demonstrated that high-frequency magnetic fields causing eddy current production could be applied to the testing of composites containing conductive fibers, or a certain amount of graphite [108.109], Eddy current testing has been successfully applied in the detection and characterization of defects in carbon fiber reinforced plastics (CFRP) panels, helicopter rotor blades, truck tires, and more [110-112]. 

S. J., Deeter, M.N., and Day, G.W. (1992) High-frequency magnetic-field sensors based on the Faraday-effect in garnet thick-films Appl. Phys. Lett. 60, p. 2048. Copyright 1992, American Institute of Physics. 

Hu HS, Liu TY, Liu DM et al (2007) Controlled pulsatile drug release from a ferrogel by a high-frequency magnetic field. Macromolecules 40 6786-6788... 

The suspension of non-ferrous metals by high-frequency magnetic fields. 

The atomization/ionization in ICP spectroscopy is accomplished via the high-temperature plasma source. The plasma is obtained by applying a high-frequency magnetic field to an ionized argon gas stream in the ICP torch device (Fig. 5). 

Stutzke, N., S.L. Burkett, and S.E. Russek. 2003. Temperature and field dependence of high-frequency magnetic noise in spin valve devices. Applied Physics Letters 82(1) 91-93. 

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