Magnetic Field Sensor (magnetic + field_sensor)

Distribution by Scientific Domains


Selected Abstracts


Magnetoelectric laminate based DC magnetic field sensor

PHYSICA STATUS SOLIDI - RAPID RESEARCH LETTERS, Issue 3 2008
Makarand Karmarkar
Abstract We report on a DC magnetic field sensor that utilizes magnetoelectric (ME) laminate composites. It consists of a ring-dot piezoelectric transformer laminated to a magnetostrictive disc. When a constant voltage is applied to the ring section of the piezoelectric layer at resonance, a stress is induced in the dot section. Then, if an external magnetic object is introduced in the vicinity of the dot section, the effective elastic stiffness is increased, altering the resonance frequency. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Sensitive In0.53Ga0.47As/InP (SI) magnetic field sensors

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 2 2004
T. Przes, awski
Abstract The usefulness of InGaAs/InP heterostructures for magnetic field sensor applications has been studied. Basic parameters of the Hall and magnetoresistive devices have been determined. Magnetic field sensitivities in a wide temperature range from 3.5 K to 300 K for layers with different carrier concentration from 2 , 1020 m,3 to 8 , 1023 m,3 have been measured. It is concluded that optimized lattice-matched InGaAs/InP heterostructures can be used as very sensitive magnetic field sensors. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Prüfung von Spannbetonbauteilen mit magnetischen Methoden

BETON- UND STAHLBETONBAU, Issue 3 2010
Gottfried Sawade Dr.
Bauwerksüberwachung; Bewehrung; Brückenbau; Spannbeton Abstract Die Methoden der magnetischen Streufeldmessung und der magnetischen Restfeldmessung eignen sich gut zur zerstörungsfreien Detektion von Spanndrahtbrüchen in Spannbetonbauteilen. Unter Verwendung eines Jochmagneten mit integrierten Magnetfeldsensoren werden die Bauteile mit mehreren Messfahrten bei verschiedenen Magnetisierungsfeldstärken abgescannt. Die Auswertung basiert auf dem Vergleich von Messungen nach verschiedenen Vormagnetisierungen sowie der Bestimmung der Korrelation mit idealisierten Bügel- und Bruchsignalen. Die Nachweisgrenze des Verfahrens wird fallabhängig diskutiert. Die Anwendung in der Prüfpraxis wird an drei Beispielen illustriert. Inspection of Prestressed Concrete Structural Members with Magnetic Methods The methods of magnetic stray field measurement and of magnetic remanence measurment are well suited for nondestructive detection of ruptures in prestressing wires of concrete structural members. Using a yoke magnet with integrated magnetic field sensors, the members are scanned several times with varying magnetization field strength. The signal analysis is based on the comparison of measurements after different premagnetizations as well as on the determination of the correlation with idealized rebar and crack signals. The limits of detection are discussed on a case-by-case basis. The application in inspection practice is illustrated with three examples. [source]