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The purpose of this paper is to present, a novel boost‐active clamp bridge single stage high‐frequency zero voltage soft‐switching‐pulse width modulation (ZVS‐PWM) inverter, which converts the utility frequency AC power into high‐frequency AC power with an embedded controller. This single stage high‐frequency inverter is composed of a single‐phase diode bridge rectifier, a non‐smoothing filter, a boost‐active clamp bridge type ZVS‐PWM high‐frequency inverter, and an induction‐heated load with planar type litz wire working coil assembly. Also, the paper discusses how to extend the soft‐switching operation ranges and improve power conversion efficiency.

The proposed converter is simulated and it is implemented using embedded controller.

It was found that the single stage high‐frequency induction heating (IH) inverter using boosted voltage function can eliminate the DC and low‐frequency components of the working coil current and reduce the power dissipation of the circuit components and switching devices.

The paper shows that the PWM HF inverter is preferred for IH, since it has reduced switching losses and switching stresses. The paper can be extended to PC‐based wireless control, which can be part of a distributed control system in major industrial heating systems.

The purpose of this paper is to develop a ferromagnetic needle adaptable for a novel ablation cancer therapy; the heat generation ability of the mild steel rod embedded into the Ti‐tube having a different thickness was investigated in a high‐frequency output at 300 kHz.

The outer diameter and length of the Ti‐tubes were 1.8 and 20 mm, respectively, while the inner diameter was varied from 1.6 to 0 mm. The mild steel rod was embedded in a Ti‐tube for preparing the needle‐type specimen. Their heat generation ability was examined by changing the inclination angle to the magnetic flux direction in a high‐frequency coil.

When the thickness of the Ti surrounding the mild steel rod was as low as 0.1 mm, the heat generation ability was drastically different among the three inclination angles (θ=0°, 45°, and 90°) to the magnetic flux direction due to the effect of the shape‐induced magnetic anisotropy. However, the effect of the inclination angle was almost eliminated in the specimen surrounded by the 0.4 mm thick Ti, suggesting that the non‐oriented heat generation property is achieved for the needle‐type mild steel rod coated with Ti having the optimum thickness.

The prototype ablation needle having a complete non‐oriented heat generation ability was fabricated to use in subsequent animal experiments. It is considered that the newly designed Ti‐coated device is useful in ablation treatments using a high‐frequency induction heating.

This paper reviews and compares the methods of kinetic heat simulation which may be used simultaneously with normal loading in structural tests of aircraft or components. Basic data on the quantities involved in and the limitations of the various techniques are given. An extensive bibliography of current literature on heat technology is provided.

This paper presents the results of a series of tests made in order to validate the magneto‐thermal module of the new FLUX3D v3.40. The tool was conceived to solve the coupled problems of electromagnetic and thermal phenomena. The solving method of the program considers a thermal‐transient problem during a certain period of time and it solves, at each time step, the thermal and electromagnetic equations (in quasi‐stationary magneto‐harmonic formulation), alternatively. We have modelled the inductive longitudinal welding of steel pipes. The results of 3D simulations are compared with measurements on a laboratory device.

Modeling of induction surface hardening strongly depends on accuracy of material properties data and their temperature characteristics. However, it is especially complicated in case of the magnetic permeability dependent not only on temperature but also on the magnetic strength. This paper aims to estimate the influence of the magnetic permeability on modeling of coupled physical fields describing the process. Investigations are provided for the gear wheels made of the steel C45E.

Computation of coupled electromagnetic temperature and hardness fields is based on FEM methods. The Flux 3D software is applied for the numerical simulation of coupled electromagnetic and temperature fields. The QT Steel software is applied for a determination of the hardness and microstructure distributions.

Obtained results may be used as a kind of background for the design of induction surface hardening systems.

The presented calculation model provided quite a good accuracy of hardness distribution validated by the experiments. Next work in the field should be aimed at taking into account a dependence of the magnetic permeability on the field current frequency.

Mathematical model of induction surface hardening with taking into account time dependence on the magnetic permeability on temperature and magnetic strength is elaborated. Experimental validation of hardness distribution is provided. A quite reasonable convergence between simulations and measurements was achieved.

The purpose of this paper is to determine technological potential of using multi‐frequency electromagnetic fields for the optimization of induction heating process.

The aim of the research is achieved by using phase‐modulated current feeding the solenoid that excites the magnetic field. In this case, the magnetic field, side by side with the carrier frequency, contains frequency spectrum arising due to modulation. At that, spectral components possess different penetration depths, which ensures a more uniform current density distribution over the cross‐section of the heated object. The results are obtained using theoretical analysis of electrodynamic and thermal processes in the heated body.

In the course of the work, a basic possibility of the objective realization is established, and its high enough efficiency is achieved using a sufficiently large range of modulation parameters.

The described method can significantly improve the technology of thermal treatment of metals and alloys liable to the formation of surface defects due to extreme temperature stresses.

The novelty of the paper consists in the use of phase‐modulated currents in induction heating.

The aim of this paper is to propose a design procedure based on the impedance boundary condition in order to simplify the design of inductors for domestic induction heating systems.

An electromagnetic description of the inductor system is performed to substitute the effects of a component, named system load, for a mathematical condition, the so‐called impedance boundary condition. This is suitable to be used in electromagnetic systems involving high conductive materials at medium frequencies, as it occurs in an induction heating system. Applying this approach, a simplified electrical model arises from the general system.

A considerable reduction in the efforts devoted to design a coil for induction heating purposes is achieved, because the solution considering the variation of three physical parameters are projected to a one‐dimensional space only depending on a single parameter named corrected penetration depth. This proposal assesses the working conditions of standard induction systems.

This work is performed to achieve a better understanding of the fundamentals involved in the electromagnetic modeling of an induction heating system. The main goal is the definition of a better coil design process because it is probably the most time‐consuming task in the construction of a complete induction system.

In this paper, the so‐called corrected penetration depth is defined. This single parameter allows explaining the influence of the physical parameter of the inductor load and the excitation frequency in the equivalent of the complete inductor system. The numerical results carried out considering the corrected penetration depth instead of the physical load properties have been validated experimentally.

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Wettability and corrosion inhibition. In the course of an ambitious research programme on corrosion inhibitors and related problems, the Institute of Chemistry at Ferrara, Italy, has investigated certain special aspects of corrosion inhibition in the presence of wetting agents. It would appear that the surface conditions have an important bearing on the mechanism of the corrosion phenomena, and that the action of the wetting agents tends to modify the distribution of the local cells so that the corrosion mechanism is re‐orientated.

Diffusion treatments may comprise the diffusion of interstitial elements such as oxygen, nitrogen, carbon, or boron into the surface from a gaseous or molten salt bath environment, or less commonly it may consist of substitutional diffusion of a previously deposited metal coating or by packing in materials such as ferromanganese or chromium with suitable additives.