RF Induction Research Articles

Magnetic Nanoparticles and Radio Frequency Induction: From Specific Heating to Magnetically Induced Catalysis

AbstractThis comprehensive review explores the potential of radio frequency (RF) induction heating in chemical reactions, explicitly focusing on magnetically induced catalysis using magnetic nanoparticles (NPs). We trace the recent historical progress of induction heating and highlight the advancements in liquid and gas‐phase reactions, particularly in its integration with heterogeneous catalysis. The review finds that induction heating profoundly impacts reaction kinetics, and selectivity, and can even reduce overpotentials in electrocatalytic processes. A final outlook unveils the challenges and opportunities associated with aspects such as fundamental research and reactor design, with a particular focus on expanding its use to higher pressures and necessary optimizations to improve energy efficiency. Moreover, it highlights the pressing need for standardized reporting in induction‐heated catalysis. The study underscores the significance of this brand‐new field in developing efficient and sustainable catalytic processes, which are essential for meeting the growing demand for clean energy and sustainable chemical production.

Preparation of spherical Gd2Zr2O7 powders by RF induction thermal plasma process

Spherical Gd2Zr2O7 (GZO) powders with a uniform particle size distribution are successfully prepared using a novel industrial approach, which combines spray-drying process and thermal plasma sintering technology together. In this, GZO powders with pyrochlore structure as the main phase are first synthesized via a solid-state reactive route using a mixture of the milled Gd2O3 powders and ZrO2 powders as starting materials. The influence of sintering temperature on the microstructure of prepared powders is researched. Then, GZO granules are prepared after wet-grinding and spray-drying process, which exhibit a spherical shape with the average particle size of 46.5 μm. RF induction thermal plasma is finally used to sinter the granulated particles, and the influence of feeding rate on the properties of spherical powders is investigated. The apparent density of plasma sintered GZO spherical powders is increased from 1.53 g/cm3 to 2.29 g/cm3 when the feeding rate of granulated powders is 80 g/min, and further increased up to 3.90 g/cm3 when the feeding rate is 15 g/min. Such powders are in potential demand for plasma sprayed coatings and additive manufacturing techniques, and the successful synthesis of spherical GZO powders may guide the way toward the preparation of many other spherical rare earth zirconates powders.

Radiofrequency Induction Heating for Green Chemicals Manufacture: A Systematic Model of Energy Losses and a Scale-Up Case-Study.

Radiofrequency (RF) induction heating has generated much interest for the abatement of carbon emissions from the chemicals sector as a direct electrification technology. Three challenges have held back its deployment at scale: reactors must be built from nonconductive materials which eliminates steel as a design choice; the viability of scale-up is uncertain; and to date the reported energy efficiency has been too low. This paper presents a model that for the first time makes a comprehensive analysis of energy losses that arise from RF induction heating. The maximum energy efficiency for radio frequency induction heating was previously reported to be 23% with a typical frequency range of 200-400 kHz. The results from the model show that an energy efficiency of 65-82% is achieved at a much lower frequency of 10 kHz and a reactor diameter of 0.2 m. Energy efficiency above 90% with reactor diameters above 1 m in diameter are predicted if higher voltage radio frequency sources can be developed. A new location of the work coil inside of the reactor wall is shown to be highly effective. Losses arising from heating a steel reactor wall in this configuration are shown to be insignificant, even when the wall is immediately adjacent to the work coil. This analysis demonstrates that RF induction heating can be a highly efficient and effective industrial technology for coupling high energy demand chemicals manufacture electricity from zero carbon renewables.

Elucidation of annealing effects on austenite–martensite and magnetic phase transitions in Mn2Ni1.6Sn0.4 ribbons synthesized from bulk alloys prepared by RF induction melting

We investigate the consequences of annealing on the structure, microstructure, magnetic, and electrical transport of Mn2Ni1.6Sn0.4 ribbons. The 40–60 μm thick ribbons were formed by melt spinning of the bulk ingot synthesized by RF induction melting. Ribbons were annealed at 600 °C for 12 hrs and the other at 800 °C for 2 hrs in vacuum. All ribbons crystallize into a cubic symmetry (space group F4¯3m). The orthorhombic phase appears as the secondary one. In ribbons annealed at 600 °C, the crystallite size decreases from ∼ 47 nm to ∼ 29 nm, and annealing at 800 °C doubles the crystallite size to ∼ 96 nm. The least amount of microstrains (17x10−4) in the as-synthesized ribbon is consistent with the occurrence of the superlattice peaks (111) and (200). Lower intensities of the superlattice peaks in 600 °C and 800 °C ribbons are consistent with higher microstrains (25x10−4 and 24x10−4). Hence, a higher degree of Ni-Mn ordering improves magnetic properties in annealed samples. The as-synthesized ribbon has an austenite-phase Curie temperature of TCA∼303K, which enhances to TCA∼320K and TCA∼310K after annealing at 600 °C and 800 °C. The ribbon annealed at 600 °C has the highest saturation moment. All the ribbons show the exchange-bias (EB) effect, and the most pronounced effect is seen in the 800 °C annealed ribbon. Microstructure uniformization and relative strengths of the Ni-Mn and Mn-Mn interactions improve the magnetics. Near TC, MT=M0TC-Tβ is satisfied (β = 0.31, 0.36, and 0.37, for as-synthesized, 600 °C and 800 °C annealed ribbons). The low-temperature spontaneous magnetization obeys the Bloch law MT=M01-AT32, with a deviation in 600 °C annealed ribbon due to spin freezing. The ρ-T has been fitted in the different temperature ranges using the various combinations in ρT=ρ0+AphT+BsdTα. At T < 85 K, the resistivity of the as-synthesized ribbon follows ρT=ρ0+BsdTα, with α≈1.47, while for the 600 °C annealed ribbon, α≈1.49. The exponent α∼1.5 supports the existence of the spin glass state in the lower temperature region of as-synthesized and 600 °C annealed ribbons. In the high-temperature range, the linear ρ-T behavior is described by ρT=ρ0+AphT and consistent with the electron–phonon scattering.

A wireless-power and data-transfer using inductive RF link and ASK modulation

This paper aims to present a novel trans-cutanaeous, wireless and an efficient radio frequency (RF) inductive power and data link (IPDL) based on amplitude shift key (ASK) - modulator with an efficient ‘Class-E’– RF ‘power amplifier’ that is applicable to implantable medical devices (IMDs). The IPDL system comprises an external device placed on exterior to human skin to transmitting power and data to IMDs like implantable micro-systems (cardiac pacemakers, cochlear implants, retinal implants, deep brain stimulators) to excite and monitor respective neural and muscular system. The entire system is designed to operate with a ‘low-band-frequency’ of 4 MHz by avoiding the problem of tissue heating. A practical model for the IPDL with results is presented. Various graphs such as frequency vs primary coil/secondary coil output are plotted and shown. Typical specifications of the exterior device, namely, the modulation-index (MI) and the modulation-rate (MR) are 40% and 4.3% respectively with a data rate of 172 Kbps. The design is simulated with electronic workbench MULTISIM 12.0 and TINA Ver 9.

Design, development, and performance of a versatile graphene epitaxy system for the growth of epitaxial graphene on SiC.

A versatile graphene epitaxy (GrapE) furnace has been designed and fabricated for the growth of epitaxial graphene (EG) on silicon carbide (SiC) in diverse growth environments ranging from high vacuum to atmospheric argon pressure. Radio-frequency induction enables heating capabilities up to 2000 °C, with controlled heating ramp rates achievable up to 200 °C/s. The details of critical design aspects and temperature characteristics of the GrapE system are discussed. The GrapE system, being automated, has enabled the growth of high-quality EG monolayers and turbostratic EG on SiC using diverse methodologies, such as confinement-controlled sublimation (CCS), open configuration, polymer-assisted CCS, and rapid thermal annealing. This showcases the versatility of the GrapE system in EG growth. Comprehensive characterizations involving atomic force microscopy, Raman spectroscopy, and low-energy electron diffraction techniques were employed to validate the quality of the produced EG.

Phase transformation of AB5 to AB2 type phase on substitution of Mn with Zr in TiVCoNi (ZrxMn2-x) (x = 0, 0.3, 0.6, 1.0) high entropy alloys

In this present investigation, we discussed the synthesis, microstructure, and phase transformation from BCC (AB5) to C14 Laves (AB2) phase in TiVCoNi (ZrxMn2-x) (x = 0, 0.3, 0.6, 1.0) high entropy alloys on substituting Mn with Zr. These high entropy alloys were synthesized using a 35 kW radio frequency induction furnace under an argon atmosphere. At x = 0 (i.e. in quinary HEA), the single BCC phase was observed, whereas at x = 1 (i.e. in hexanery HEA), the single C14 Laves phase was found to be stable. The calculations of the thermodynamic parameters were done with the help of Miedema's semi-empirical model and other models available in the literature. TiVCoNi (ZrxMn2-x) high entropy alloys exhibited mixing enthalpy at x = 0, 0.3, 0.6, 1 as −15.6 kJ/mol, −18.1 kJ/mol, −22.8 kJ/mol, −25.3 kJ/mol respectively. The corresponding atomic size mismatch was found to be 10.03%, 11.85%, 10.18%, and 9.86%. It is established that on replacing Mn with Zr, the mixture of the BCC and Laves phase was observed, which was converted into a single C14 intermetallic Laves phase at equiatomic composition, i.e., x = 1. Further, the study of surface morphology and elemental composition of these as-cast high entropy alloys gives us the idea that hardness increases on substitution of Mn in BCC (at x=0) phased-based; TiVCoNi (ZrxMn2-x) (x = 0, 0.3, 0.6, 1.0) high entropy alloys due to the evolution of harder C14 Laves phase.

Stealth RF energy harvesting in MRI using selective shielding.

To utilize the transmit radiofrequency (RF) field in MRI as a power source, near or within the field of view but without affecting image quality or safety. Power harvesting is performed by RF induction in a resonant coil. Resulting RF field distortion in the subject is canceled by a selective shield that couples to the harvester while being transparent to the RF transmitter. Such shielding is designed with the help of electromagnetic simulation. A shielded harvester of 3 cm diameter is implemented, assessed on the bench, and tested in a 3T MRI system, recording power yield during typical scans. The concept of selective shielding is confirmed by simulation. Bench tests show effective power harvesting in the presence of the shield. In the MRI system, it is confirmed that selective shielding virtually eliminates RF perturbation. In scans with the harvester immediately adjacent to a phantom, up to 100 mW of average power are harvested without affecting image quality. Selective shielding enables stealthy RF harvesting which can be used to supply wireless power to on-body devices during MRI.

Similarity rules for inductive radio frequency plasmas with thermohydrodynamic coupling effects

We demonstrate similarity rules for inductively coupled plasmas with thermohydrodynamic coupling effects using two-dimensional fluid simulations and theoretical analyses of the gas flow and heat transfer equations. The results confirm the validity of conventional similarity laws, e.g., the similarity relation for electron density, which can be violated by the nonlinear gas heating effects from exothermic and endothermic reactions. The nonlinear gas heating can obviously perturb the invariance of spatial distributions of the gas flow velocity, resulting in the electron density decreasing nonproportionally with different scaling factors. Adding an external heat source can mitigate the violation of the gas temperature scaling law, thus maintaining the validity of similarity relations to some extent. In addition, two kinds of scaling relations for excited-state argon atoms are identified with and without the consideration of nonlinear collisions.

Synthesis of single‐phase high‐entropy diboride powders and their spheroidization process

AbstractSpherical (Zr.2Ti.2Ta.2Nb.2Mo.2)B2 powders with a uniform particle size distribution are successfully prepared using a novel industrial approach, which combines spray‐drying process and thermal plasma sintering technology together. In this, single‐phase (Zr.2Ti.2Ta.2Nb.2Mo.2)B2 powders are first synthesized via a borothermal reduction process using a mixture of individual metallic oxides and boron powders as starting materials. The influence of boron powder content on the structure of prepared powders is researched. Then, (Zr.2Ti.2Ta.2Nb.2Mo.2)B2 granules are prepared after wet‐grinding and spray‐drying process, which exhibit a spherical shape and homogeneous element distribution. RF induction thermal plasma is finally used to sinter the granulated particle, and the apparent density of sintered spherical powders is increased to 2.57 g/cm3 from 1.43 g/cm3. Such powders are in potential demand for additive manufacturing techniques, and the successful synthesis of spherical (Zr.2Ti.2Ta.2Nb.2Mo.2)B2 powders may guide the way toward the preparation of many other spherical high‐entropy diboride powders.

Investigations on phase formation and magnetic properties of promisingCo35Cr5Fe10Ni30Ti20 high entropy alloysynthesized through radio frequency induction melting

Previously, we designed and developed a promising excellent soft magnetic Co35Cr5Fe10Ni30Ti20High Entropy Alloy (HEA) through mechanical alloying (MA) followed by annealing at 790 ̊C. Densification of the powder sample synthesized through MA is critical for industrial a pplications, particularly as amagnetic material. Therefore, in the present study,optimizedCo35Cr5Fe10Ni30Ti20 HEA is synthesized again through the radio frequency (RF) induction melting.The X-ray diffraction (XRD) analysis of the RF induction melted HEA revealed the formation of mixture of fcc and ordered B2 phase. The phase stability of synthesized HEA has also been investigated through annealing at 790 °C for 2 h. Thesynthesized HEA maintained its phase identity after annealing. The synthesized and annealed Co35Cr5Fe10Ni30Ti20HEAs showed ferromagnetic behavior with high saturation magnetization (Ms) and low coercivity (Hc). For as-synthesized Co35Cr5Fe10Ni30Ti20 HEA, the value of Ms and Hcis found to be 80.22 emu/g and 4.63 Oe, respectively. However, after annealing, the value of Hcis increased to 7.89 Oe, while Ms remained same to as synthesized HEA.Vickers hardness test was also performed on the synthesized and annealed HEAs. The results displayed that hardness increased after annealing upto 512.50 Hv. The present studynot only investigates phase formation and magnetic properties of RF induction melted HEA but it also emphasizes the effect of the processing route on the structural, magnetic, and mechanical properties of the most promising magnetic Co35Cr5Fe10Ni30Ti20 HEA. The found value of hardness for the RF- melted Co35Cr5Fe10Ni30Ti20 HEA is excellent as compared to the conventional soft magnetic materials such as polycrystalline Fe (100–150 Hv), Fe50Ni50 (120 Hv) etc. The present investigation is also important for the industrial development of the magnetic Co35Cr5Fe10Ni30Ti20 HEA.

Numerical simulation of thermal-fluid field and vortex flow pattern in the RF induction plasma under atmospheric pressure

大气压射频热等离子体由于高比焓、低流速以及无电极污染，近年来广泛应用于粉末球化、耐烧蚀涂层喷涂和纳米粉体合成等领域。本文基于二维轴对称磁流体方程组，建立大气压氩气射频热等离子体仿真模型，研究了不同工况和结构参数下放电管内等离子体温度场、速度场以及焦耳热、辐射耗散和洛伦兹力分布特征。重点研究了放电高温区域前端涡流场形态及其形成的原因，讨论了两种不同涡流形态之间的转变条件，并计算了不同线圈功率，放电频率、中心管内径和出口位置条件下涡流形态转变所需的中心气体临界流量，研究结果为射频热等离子体工况参数的选取以及中心管粉末供给系统的设计提供重要理论依据。

Simultaneous improvement of heating efficiency and mechanical strength of a self-healing thermoplastic polymer by hybridizing magnetic particles with conductive fibres

Radio-Frequency (RF) induction heating is a versatile in-situ method for contactless heating of structures by utilizing either magnetic hysteresis loss or eddy-current loss mechanism. Achieving high heating efficiency without degrading mechanical properties is a major challenge. Herein, a RF induction compatible self-healing composite was developed by hybridizing iron oxides (Fe3O4) nanoparticles with carbon fibre veils (CFVs) in poly(ethylene-co-methacrylic acid) (EMAA), which could possess both high magnetic and electrical properties. Owing to the multiscale conductive networks built by Fe3O4 nanoparticles and CFVs, the electrical conductivity of the nanocomposite was found to be higher than the linear combination of the individual contributions, thus creating a synergistic improvement in electrical conductivity and heating efficiency. Furthermore, single lap shear test results demonstrated that the combination of Fe3O4 nanoparticles and CFVs could significantly improve the bonding strength of EMAA polymer. Therefore, the hybridization of magnetic particles with conductive fibres offers a promising technology for a wide range of applications, such as self-healing, reversable bonding, and multiple use bonded composites.

A Comparative Study on the Effect of Different Sintering Temperatures on Structural and Magnetic Properties of Mg–Zn Ferrite Nanoparticles

The current study involved the synthesis of magnesium zinc ferrite (Mg0.8Zn0.2Fe1.4Al0.6O4) using the sol–gel method. Various techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier Transform Infrared (FTIR), vibrating sample magnetometer (VSM), and radiofrequency (RF) induction were utilized to analyze the properties of the synthesized ferrite nanoparticles. The objective was to examine how different sintering temperatures affected the structural and magnetic characteristics of Mg0.8Zn0.2Fe1.4Al0.6O4. The XRD analysis confirmed the presence of a well-defined single phase crystalline structure with a spinel arrangement. Increasing the annealing temperature resulted in larger nanoparticles, ranging from 28.38 nm to 30.14 nm. SEM provided information about the morphology, agglomeration, and grain size of the ferrite, revealing a grain size ranging from 326 nm to 485 nm. The FTIR spectroscopy indicated a single-phase spinel structure for the prepared sample. The magnetic properties of the sample were evaluated using VSM, showing a maximum magnetization of 45.6 emu/gm and the least coercivity of 90 Oe at an annealing temperature of 900 °C. RF induction at a frequency of 108 kHz exhibited superior results for the sample annealed at 900 °C compared to those annealed at 700 °C and 800 °C. At this frequency, the specific absorption rate (SAR) value was high, making it suitable for magnetic hyperthermia applications. The prepared magnesium zinc ferrite demonstrated suitability for both low and high frequency devices, and it could be employed in various technological applications, including microwave devices, inductor cores, transformers, and other electronic devices.

Plasma Parameters and Kinetics of Reactive Ion Etching of SiO2 and Si3N4 in an HBr/Cl2/Ar Mixture

The parameters of the gas phase and the kinetics of reactive ion etching of SiO2 and Si3N4 under conditions of an induction RF (13.56 MHz) discharge with a varying HBr/Cl2 ratio is studied. The study includes plasma diagnostics using Langmuir probes, plasma modeling to find stationary concentrations of active particles, measuring velocities, and analyzing etching mechanisms in the effective interaction prob-ability approximation. It is found that the substitution of HBr by Cl2 at a constant argon content (a) is accompanied by a noticeable change in the electrical parameters of the plasma; (b) leads to a weak increase in the intensity of ion bombardment of the treated surface; and (c) causes a significant increase in the total concentration and flux density of reactive particles. It is shown that the etching rates of SiO2 and Si3N4 increase monotonically as the proportion of Cl2 increases in a mixture, while the main etching mechanism is an ion-stimulated chemical reaction. The model description of the kinetics of such a reaction in the first approximation assumes (a) the additive contribution of bromine and chlorine atoms and (b) the direct pro-portional dependence of their effective interaction probabilities on the intensity of ion bombardment. The existence of an additional channel of heterogeneous interaction with the participation of HCl molecules is proposed.

Security of underwater and air–water wireless communication: State-of-the-art, challenges and outlook

The technologies used in underwater and air–water (A–W) wireless communication networks (WCN) are increasingly attracting attention due to numerous modern applications, e.g., internet of underwater things etc. However, for practical implementations of these modern applications, the security of the underwater and A–W WCNs needs to be ensured beforehand. Thus, the main focus of this survey is to systematically discuss the security needs of underwater and A–W WCNs, and solutions proposed to date. Before extending our discussion on security, we initially cover the fundamentals of underwater and A–W WCNs. First, we provide a comprehensive overview of different underwater communication technologies: radio frequency (RF), acoustic, optical, and magnetic induction (MI) in terms of channel characteristics, merits, and demerits. The discussion is further extended to A–W wireless communication by presenting direct and indirect (relay-aided) techniques. Then we present the primer on information security which highlights the four fundamental properties of security (i.e., confidentiality, integrity, authentication, and availability) and security solutions (i.e., cryptography and physical layer security) built for the considered underwater communication technologies. In addition, we discuss at length the security aspects of the underwater and A–W WCNs by reviewing and summarizing the existing work in the literature. We notice that the related work on security of RF-based, magnetic induction-based underwater WCNs, and A–W WCNs is practically non-existent. Thus, we highlight this research gap in the literature, and propose a few additional security-related open problems too, that we believe deserve to receive more attention from the underwater, marine, and oceanic research community.

Preparation of spherical WC-Co powder by spray granulation combined with radio frequency induction plasma spheroidization

In this paper, spray granulation and radio frequency plasma spheroidization were used to obtain spherical WC-Co powder for laser powder bed fusion from mixed WC and Co powder. The effects of solid content and polyvinyl alcohol content of the slurry on granulated powder were studied. Then the spheroidization effects of different granulated WC-Co powders were investigated and compared. Results show that the granulated powder obtained from the slurry with solid content of 65 wt% and polyvinyl alcohol content of 2.5 wt% has the best performance after plasma spheroidization, whose flowability and apparent density are 10.20 s/50g and 6.76 g/cm3, respectively. Moreover, W and C distribute uniformly in the spheroidized WC-Co powder while the Co element is mainly distributed in the gaps of tungsten carbide. It is also noted that W2C, free carbon and Co3W3C appear in the spheroidized WC-Co powders due to the decomposition of WC during the plasma spheroidization process. Furthermore, the decomposition of WC-Co powder particles with smaller size is more serious, which leads to the presence of black and white particles with significantly different carbon content distribution in the spheroidized powder.

Pre-Exposure to Radiofrequency Electromagnetic Fields and Induction of Radioadaptive Response in Rats Irradiated with High Doses of X-Rays

Background: Some evidence shows that a pre-exposure to RF can mitigate the effects of subsequent exposures to high doses of ionizing radiation.Objective: We aimed to assess the effect of a pre-exposure to non-ionizing RF radiation on survival, weight changes, food consumption, and water intake of lethally irradiated rats.Material and Methods: In this case-control study, we used a commercial mobile phone (GSM, 900/1800 MHz) as well as a 2.4 GHz Wi-Fi router as the sources of pre-exposure to RF radiation. Forty-eight rats were randomly divided into six groups of control, “8 Gy X-rays”, mobile phone, “mobile phone+8 Gy”, Wi-Fi, and “Wi-Fi+8 Gy”. Then, the survival fraction, weight loss, water, and food consumption changes were compared in different groups. Results: The survival analysis indicated that the survival rates in all of the exposed animals (“8 Gy X-rays”, “mobile phone+8 Gy”, “Wi-Fi+8 Gy”) were significantly lower than the control, “Wi-Fi”, and “mobile phone” groups. The changes in survival rates of “mobile+8 Gy”, “Wi-Fi+8 Gy”, and 8 Gy alone were not statistically significant. However, food and water intake were significantly affected by exposure to both RF pre-exposures and exposure to high dose ionizing radiation.Conclusion: To the best of our knowledge, the existence of a dose window for the induction of AR can be the cause of the lack of AR in our experiment. Our findings confirm that in a similar pattern with the adaptive responses induced by pre-exposure to ionizing radiation, the induction of adaptive response by RF-pre-exposures requires a minimum level of damage to trigger adaptive phenomena.

Liquid Metal-Elastomer Composites with Dual-Energy Transmission Mode for Multifunctional Miniature Untethered Magnetic Robots.

Miniature untethered robots attract growing interest as they have become more functional and applicable to disruptive biomedical applications recently. Particularly, the soft ones among them exhibit unique merits of compliance, versatility, and agility. With scarce onboard space, these devices mostly harvest energy from environment or physical fields, such as magnetic and acoustic fields and patterned lights. In most cases, one device only utilizes one energy transmission mode (ETM) in powering its activities to achieve programmed tasks, such as locomotion and object manipulation. But real-world tasks demand multifunctional devices that require more energy in various forms. This work reports a liquid metal-elastomer composite with dual-ETM using one magnetic field for miniature untethered multifunctional robots. The first ETM uses the low-frequency (&lt;100Hz) field component to induce shape-morphing, while the second ETM employs energy transmitted via radio-frequency (20kHz-300GHz) induction to power onboard electronics and generate excess heat, enabling new capabilities. These new functions do not disturb the shape-morphing actuated using the first ETM. The reported material enables the integration of electric and thermal functionalities into soft miniature robots, offering a wealth of inspirations for multifunctional miniature robots that leverage developments in electronics to exhibit usefulness beyond self-locomotion.

Reflected impedanceometry: a contact-free technique for measuring induced magnetic hysteresis and eddy current heating

Reflected Impedanceometry is a new technique that can remotely measure the power absorbed during radiofrequency induction heating. It measures the total system impedance from the phase difference between current and voltage in the electromagnetic field work coil and uses the characteristic impedance of the work coil circuit to infer the heating power transferred into a susceptor bed. Induction heating of susceptor materials within alternating magnetic fields occurs by magnetic hysteresis, eddy currents, Néel relaxation or Brownian relaxation. It shows potential for replacing fossil fuels with renewable electricity in carbon-intensive industrial applications but requires advances in measurement techniques. Previously developed methods for measuring heating power, such as pick-up coils, are limited to applications involving magnetic materials. Results presented here show that reflected impedanceometry accurately measures heating power for both magnetic hysteresis and eddy currents, fulfilling the requirement for measuring induction heating power.