Effect of particle diameter and packing density on heating of metallic iron particles in alternating magnetic field

The heat losses originated from the electro-magnetic absorption in mechanically packed metallic iron nano- and micro-sized magnetic particles (MPs) and in magnetic epoxybased composites with embedded MPs were studied by Calvet microcalorimetry. Nano-sized MPs with numerical average diameter 40 nm were synthesized by electrical explosion of wire method; micro-sized MPs with numerical average diameter 2 μm were synthesized by flame decomposition of the iron pentacarbonyl. The specific loss power (SLP) of re-magnetization of press-packed powdered samples and epoxy composites in magnetic field 1750 A/m at 214 kHz was measured as a function of the volume fraction of MPs in the sample. The results showed up that SLP depended both on particle size and on volume fraction, which meant the significant effect of magnetic interaction among particles on the heat losses in electromagnetic absorption. © Published under licence by IOP Publishing Ltd.Russian Foundation for Basic Research, RFBR: 18-08-00178Russian Academy of Sciences, RASThe study has been done with the financial support of RF State Assignment of IEP UB RAS as well as of the Russian Foundation of Basic Research, project 18-08-0017

Electomagnetic absorption of composites based on epoxy resin and metallic iron nanoparticles

The heat losses originated from the electro-magnetic absorption in magnetic epoxy-based composites with embedded metallic iron nanoparicles were studied by Calvet microcalorimetry. Iron magnetic nanoparticles (MNPs) were synthesized by electrical explosion of wire (EEW) method; they were non-agglomerated, spherical in shape and had a weight average diameter 85 nm. Composites based on the cured epoxy-dian resin contained MNPs in weight content varying from 10% up to 70%. To study the heat loss in alterating magnetic field commercial Calvet microcalorimeter was equiped by two coils in the serial connection placed in the calorimeter cells; one of the coils contained a sample of composite the other was a reference. The electromagnetic adsorption was studied in the alternating magnetic field up to 1700 A/m in 67-214 kHz frequency range. The measured values of the specific power losses revealed linear dependence on iron MNPs content in composite and non-linear increasing function of the field frequency. © 2018 The Authors, published by EDP Sciences.This work is supported in part by the project for basic research of UD RAS. The assistance of Shchipanova T. A. in the measurements of hysteresis loops for composites is appreciated

THERMODYNAMIC BEHAVIOR AND MECHANICAL PROPERTIES OF COMPOSITES BASED ON EPOXY RESIN AND IRON NANOPARTICLES

Interfacial adhesion of Fe nanoparticles to the epoxy resin KDA in the entire composition range was studied by Calvet calorimetry. Mechanical Behavior was studied by mechanical tests of crosslinked composites based on epoxy resin KDA with Fe nanoparticles