An air-cooled Litz wire coil for measuring the high frequency hysteresis loops of magnetic samples : a useful setup for magnetic hyperthermia applications

摘要

A low-cost and simple setup for measuring the high-frequency hysteresis loopsof magnetic samples is described. An AMF in the range 6-100 kHz with amplitudeup to 80 mT is produced by a Litz wire coil. The latter is air-cooled using aforced-air approach so no water flow is required to run the setup.High-frequency hysteresis loops are measured using a system of pick-up coilsand numerical integration of signals. Reproducible measurements are obtained inthe frequency range of 6-56 kHz. Measurement examples on ferrite cylinders andon iron oxide nanoparticle ferrofluids are shown. Comparison with othermeasurement methods of the hysteresis loop area (complex susceptibility,quasi-static hysteresis loops and calorific measurements) is provided and showsthe coherency of the results obtained with this setup. This setup is welladapted to the magnetic characterization of colloidal solutions of MNPs formagnetic hyperthermia applications.