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

V Connord; B Mehdaoui; R P Tan; J Carrey; M Respaud

doi:10.1063/1.4895656

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

Rev Sci Instrum. 2014 Sep;85(9):093904. doi: 10.1063/1.4895656.

Authors

V Connord¹, B Mehdaoui¹, R P Tan¹, J Carrey¹, M Respaud¹

Affiliation

¹ Laboratoire de Physique et Chimie des Nano-objets (LPCNO), Université de Toulouse, INSA, UPS, CNRS (UMR 5215), 135 avenue de Rangueil, F-31077 Toulouse, France.

PMID: 25273736
DOI: 10.1063/1.4895656

Abstract

A setup for measuring the high-frequency hysteresis loops of magnetic samples is described. An alternating magnetic field in the range 6-100 kHz with amplitude up to 80 mT is produced by a Litz wire coil. The latter is air-cooled using a forced-air approach so no water flow is required to run the setup. High-frequency hysteresis loops are measured using a system of pick-up coils and numerical integration of signals. Reproducible measurements are obtained in the frequency range of 6-56 kHz. Measurement examples on ferrite cylinders and on iron oxide nanoparticle ferrofluids are shown. Comparison with other measurement methods of the hysteresis loop area (complex susceptibility, quasi-static hysteresis loops, and calorific measurements) is provided and shows the coherency of the results obtained with this setup. This setup is well adapted to the magnetic characterization of colloidal solutions of magnetic nanoparticles for magnetic hyperthermia applications.