Induction Heating Research Articles

Warpage control and interface characteristics of Ti/Al composite plates by differential temperatures rolling with mobile induction heating

This study addresses the issue of warping and low interfacial bonding strength in composite plates due to uncoordinated deformation during the rolling of titanium/aluminum composites. By adopting mobile induction heating with differential temperature rolling composite technology, heated titanium plates and room-temperature aluminum plates were successfully rolled into composites. The results show that when the titanium plate is heated to 500–900°C, the warpage of the titanium/aluminum composite plates first decreases and then increases, while the interface shear strength first increases and then decreases. It is particularly emphasized that the rolled composite plates is straight at 800°C, the Ti6O oxide layer formed on the titanium plate surface exhibits excellent adhesion to the substrate, while displaying susceptibility to cracks during the rolling process, allowing fresh aluminum metal to be squeezed into the cracks to form a mechanical mesh and an atomic bonding diffusion layer occurs due to the fresh metal contact between titanium and aluminum within the crack, thereby resulting in the composite plates exhibiting optimal shear strength. The findings verify the preliminary feasibility of the proposed novel rolling process and provide a novel solution for prepared titanium/aluminum composite plates, which is an important step for future fabrication and applications of composite plates.

Study on L-Bending Springback of 45 Steel Leather Cutting Tool Coupled with Local Induction Heating

Study on L-Bending Springback of 45 Steel Leather Cutting Tool Coupled with Local Induction Heating

Sub-minute carbonization of polymer/carbon nanotube films by microwave induction heating for ultrafast preparation of hard carbon anodes for sodium-ion batteries

Hard carbons (HCs) are excellent anode materials for sodium-ion batteries (SIBs). However, the carbonization and granulation of HC powders involve complex processes and require considerable energy. Here, we developed a facile method for manufacturing HC anodes for SIBs via a novel microwave induction heating (MIH) process for polymer/single-walled carbon nanotube (SWCNT) films. Numerical simulations solving electromagnetic field and heat transfer problems revealed the MIH mechanism; the electric current induced by the applied microwave enables direct Joule heating of the SWCNT networks in the composite film. Consequently, the composite films could be heated to the target temperatures (800–1400 °C) and free-standing HC/SWCNT anodes could be prepared by applying MIH for only 30 s. Comparative analyses confirmed that ultrafast MIH is a reliable technique for producing HC anodes and can replace conventional carbonization processes which require a high-temperature furnace. Moreover, the HC/SWCNT anodes prepared by the ultrafast MIH were successfully applied to the SIB full cells. Finally, the feasibility of MIH for scalable roll-to-roll production of HC anodes was verified through local heating tests using a circular sheet larger than a resonator.

Amaiur Mendi Altube - Modeling and Design of Induction Heating Systems

Amaiur Mendi Altube - Modeling and Design of Induction Heating Systems

Modeling and Design of Induction Heating Systems

This thesis is based on a specific industrial application of induction heating technology: induction hardening. The main objective is to create a simulation model that predicts the whole heating process, combining the electrical simulation with the electromagnetic-thermal analysis, employing electrical simulation software and finite element tools, respectively. This proposed model will be called as dynamic model in the following lines.

Minimizing Porosity in 17-4 PH Stainless Steel Compacts in a Modified Powder Metallurgical Process

Nowadays, powder-based manufacturing processes are recognized as cost-efficient methods frequently employed for producing parts with intricate shapes and tight tolerances in large quantities. However, like any manufacturing method, powder-based technologies also have several disadvantages. One of the most significant issues lies in the degree of porosity. By modifying the morphology of the gas-atomized spherical 17-4PH stainless steel powder via prior ball milling and then raising both the pressure of cold compaction (1.6 GPa) and sintering temperature (1275 °C), the porosity could be reduced considerably. In our novel powder metallurgical (PM) experimental process, an exceptionally high green density of 92% could be reached by employing die wall lubrication instead of internal lubrication and utilizing induction heating for rapid sintering. After sintering (at temperatures of 1200, 1250, and 1275 °C), the samples aged in the H900 condition were then mechanically tested (Charpy impact, HV hardness, and tensile tests) as a function of porosity. Sintering at 1275 °C for one hour enabled porosity reduction to below 4%, resulting in 1200 MPa yield strength and 1350 MPa ultimate tensile strength with significant (16%) fracture strain. These values are comparable to those of the same alloy products fabricated via ingot metallurgy (IM) or additive manufacturing (AM).

The effect of fibers addition on the microstructure and mechanical properties of ZrO2 fibers toughened Al2O3/ZrO2 (Y2O3) solidified ceramics

Fiber toughening is considered an effective way to strengthen the toughness of traditional sintered ceramics. Herein, ZrO2 fibers toughened Al2O3/ZrO2 (Y2O3) directionally solidified eutectic ceramics (DSECs) were prepared with the high-frequency induction heating zone melting (IHZM). The effects of ZrO2 fibers content on the phase composition, microstructure, and mechanical properties of the eutectic ceramics were studied. The findings revealed that DSEC consists of α-Al2O3 and ZrO2 phases, presents a typical colony microstructure. The phase spacing in the colony decreased with the addition of fibers, reaching a minimum value of 1.99 ± 0.25 μm at 20 wt%, which was nearly 40 % lower than that without the fiber’s addition. The hardness of DSEC increased gradually with the addition of fibers. Its highest value reaches 18.42 ± 0.55 GPa when the fiber content is 20 %. The fracture toughness of DSEC first increased and then decreased, reaching a maximum of 5.43 ± 0.22 MPa·m1/2 at 10 wt%, which was 1.5 times higher than that of the fibers-free eutectic ceramic. The improvement of fracture toughness was primarily due to the fibers toughening. In addition, the crack deflection, pinning, bridging, and branching had a significant inhibitory effect on the crack propagation.

Widely targeted metabolomics analysis of nutrient changes in a new black rice variety ‘Huamoxiang No.3’ (Oryza sativa L. var. Glutinosa Matsum) under different cooking modes

AbstractBackgroundBlack rice is rich in various nutrients, such as anthocyanins, which may undergo some changes during cooking. However, previous studies have been mainly focused on a single substance and paid less attention to the changes in overall nutrient components. Here, we performed widely targeted metabolomics analysis on the chemical compositional changes in a new black rice variety (‘Huamoxiang No.3’) under three cooking modes, including bottom heating (BH), induction heating (IH), and IH + pressure.ResultsAmong the detected 1458 metabolites, 276 and 108 metabolites were differential metabolites after cooking and in three cooking modes, respectively. Cooking increased the contents of most peptides, phenolic acids, and organic acid compounds but significantly decreased those of lipids and flavonoids, particularly anthocyanins. However, phenolic acids such as chlorogenic acid, erucic acid, and p‐coumaric acid increased significantly, possibly due to the release of bound phenols and degradation of flavonoids to phenolic acids, such as thermal degradation of C3G to protocatechuic acid and among the three heating modes, the IH + pressure mode resulted in the most significant changes.ConclusionAlthough cooking reduced the content of flavonoids and anthocyanins, the increase in phenolic acids and other substances contributed to the healthy effect of cooked black rice, and the content of these active substances increased more significantly in the IH + pressure mode.

A novel heat-inducible plasmid-driven T7 system for enhancing carbonic anhydrase in engineered Escherichia coli strains

Over the past decades, the heat-inducible (HI) promoter, derived from cI857 phage system has been widely utilized. However, the developments of alternative temperature-controlled promoters are limited. In this study, we explored a novel HI promoter through PCR amplification using the degenerate primer design. BLAST analysis identified this sequence as a partial plsB on Escherichia coli chromosome. Antisense RNAs targeting distinct regions of HI promoter were applied to examine the mechanism. The fluorescence of super-folder green fluorescent protein (sfGFP) driven by the HI promoter showed 5.5-fold increase from 30 to 42 °C, whereas the truncated HI yielded a trace amount of sfGFP. Among various E. coli strains, BL21 exhibited the highest fluorescence, reaching 3976 a.u. at 42 °C. Subsequently, the novel HI promoter was employed to drive T7RNA polymerase within a plasmid-driven T7 (PDT7) plasmid, serving its capability to express sfGFP and carbonic anhydrases (CA), respectively. The maximum intensity of sfGFP reached 38,702 a.u., and CA activity surged to 14286 WAU/mL in W3110 among other strains. Finally, the highest CA activity was 27,521 WAU/mL at pH 9. The promising results from the novel heat-inducible promoter-driven T7RNAP, incorporating the T7 terminator as HI-PDT7-TT, demonstrate potential for expressing more heterogeneous proteins across various chassis in the future.

Energy‐based PINNs for solving coupled field problems: Concepts and application to the multi‐objective optimal design of an induction heater

AbstractPhysics‐informed neural networks (PINNs) are neural networks (NNs) that directly encode model equations, like Partial Differential Equations (PDEs), in the network itself. While most of the PINN algorithms in the literature minimize the local residual of the governing equations, there are energy‐based approaches that take a different path by minimizing the variational energy of the model. It is shown that in the case of the steady thermal equation weakly coupled to magnetic equation, the energy‐based approach displays multiple advantages compared to the standard residual‐based PINN: it is more computationally efficient, it requires a lower order of derivatives to compute, and it involves less hyperparameters. The analyzed benchmark problems are the single‐ and multi‐objective optimal design of an inductor for the controlled heating of a graphite plate. The optimized device is designed by involving a multi‐physics problem: a time‐harmonic magnetic problem and a steady thermal problem. For the former, a deep neural network solving the direct problem is supervisedly trained on Finite Element Analysis (FEA) data. In turn, the solution of the latter relies on a hypernetwork that takes as input the inductor geometry parameters and outputs the model weights of an energy‐based PINN (or ePINN). Eventually, the ePINN predicts the temperature field within the graphite plate.

Enhancing self-healing of asphalt mixtures containing recycled concrete aggregates and reclaimed asphalt pavement using induction heating

Given the growing demand for sustainable road construction materials, this research aims to evaluate the synergistic effects of incorporating recycled concrete aggregate (RCA) and reclaimed asphalt pavement (RAP) in asphalt mixtures. Induction heating was also utilized to enhance the self-healing ability of asphalt mixtures, with the intention of prolonging their lifespan and mitigating environmental impacts. This research assessed the pavement performance of recycled asphalt mixtures (RAM) with different RCA and RAP dosages. The induction heating performance, cooling performance, and effective heating depth of RAM were tested. Lastly, the cumulative healing efficiency of the RAM was evaluated under multiple "fracture-healing" conditions. Findings indicated that the inclusion of RCA and RAP negatively influenced the water stability, high-temperature deformation resistance, and crack resistance at low temperatures of the RAM. However, when the RCA content was 20 % and the RAP content did not exceed 20 %, the road performance of the RAM met the requirements. The contents of the RCA and RAP had no discernible effect on the RAM's induction heating capability. Moreover, when the RCA content was 20 % and the RAP content did not exceed 10 %, the effective heating depth of the RAM could reach 50 mm. Using fracture energy recovery rate as the healing index, after three cycles of "fracture-healing", the RAM with 20 % RCA achieved the highest cumulative healing efficiency of 291 %. The cumulative healing efficiency of recycled asphalt mixtures with 20 % RCA and 10 % RAP was close to that of normal asphalt mixtures. This research contributes to reducing the consumption of non-renewable resources, minimizing environmental impact, and maintaining or even improving the performance of asphalt pavements by optimizing the use of RCA and RAP.

Problem-oriented numerical model of the process of tailored induction heating of a steel cylindrical billet

Problem-oriented numerical model of the process of tailored induction heating of a steel cylindrical billet

CF/PEEK skins assembly by induction welding for thermoplastic composite sandwich panels

A method to assemble sandwich panels made of carbon fibre reinforced poly-ether-ether-ketone (CF/PEEK) facesheets and 3D-printed poly-ether-imide (PEI) honeycomb cores using induction welding is presented. Induction heating patterns inside CF/PEEK laminates of variable dimensions are first evaluated with a thermal camera and compared to a COMSOL Multiphysics model. Sandwich samples are then prepared by vacuum-assisted continuous induction welding under parameters selected from the modelling effort. Joining of sandwich panels made of CF/PEEK facesheets by induction welding under vacuum is demonstrated. Facesheets do not deconsolidate in the process and core crushing is avoided. Flatwise skin/core strength of the welded samples reaches up to 7 MPa, above reported performance for thermoset or thermoplastic composite sandwich panels.

Efficiency Optimization in Parallel LLC Resonant Inverters with Current-Controlled Variable-Inductor and Phase Shift for Induction Heating

This paper presents a comprehensive analysis of a novel control approach to improve the efficiency of parallel LLC resonant inverters using a combination of a current controlled variable inductor (VI) and phase shift (PS). The proposed control aims to reduce the Root Mean Square (RMS) current, thereby reducing conduction and switching losses, and improving power transfer efficiency, while considering zero-voltage-switching (ZVS) operation, output power variations and load changes. Furthermore, a design methodology for the variable inductor is proposed, and design considerations relevant to this application are discussed. The effectiveness of the proposed approach is evaluated through mathematical modeling and experimental results. The mathematical modeling results show that the proposed approach, utilizing SiC MOSFETs, maintains a maximum efficiency of 98.5% for a 20 kW inverter over a wider range of output power, which is a significant improvement over existing approaches. The experimental results also confirm the effectiveness of the proposed control in improving the efficiency of parallel LLC resonant inverters.

Physicochemical characteristics of solid-phase reduction of pellets (briquettes) under induction heating

A new method for organizing the solid-phase reduction of pellets (briquettes) using induction heating was proposed, and the physicochemical aspects of the heating and reduction processes were investigated. A thermodynamic analysis of the reactions during solid-phase reduction was carried out; the equilibrium composition of the gaseous phase in the Fe–O–C and Mn–O–C systems was determined, and the thermodynamically permissible temperature of iron oxide reduction initiation at different values of =РСО+РСО2 were established. The results of calculating the rate of heating of coal and ore concentrate by the metallic component of the pellets (briquette) were analyzed both under condition of the flow of chemical reactions and in the absence of chemical transformation. The experiments demonstrated the fundamental possibility of heating and reducing iron oxides inside the volume of the pellet, as well as conducting both solid-phase reduction and melting of the reduced iron to obtain liquid steel under induction furnace melting conditions.

Enhanced interlayer strength in 3D-printed PA12 composites via electromagnetic induction post-processing

Weak interlayer strength remains a critical limitation in the application of material extrusion 3D-printed parts. Herein, a non-contact method, electromagnetic induction post-processing, is proposed to address this issue. This method aims to enhance the weak interlayer strength of 3D-printed PA12 samples by introducing Fe3O4 particles for induced heat generation under alternating magnetic fields. The heat generation characteristics, surface morphology, crystallization behavior, and interlayer performance of 3D-printed samples subjected to induction post-processing are systematically investigated. The results indicate that a remarkable improvement in the interlayer strength of 3D-printed PA12 samples can be achieved through induction post-processing. Tensile strength along the Z-direction (perpendicular to the printing plane) exhibits a distinct increase of 218.3 %, while interlayer tear strength can rise by 328.1 %. Improvement in interlayer strength results from heat generation driving interfacial resin diffusion. Additionally, induction post-processing results in localized surface smoothing and a slight reduction in the crystallinity of the 3D-printed sample. Compared to traditional methods like in-oven heat treatment (annealing), induction post-processing offers higher efficiency by circumventing the initial constraints of heat transfer. Furthermore, the concept of selective induction heating (SIH) is proposed to achieve non-contact, localized heating by adjusting the composition of thermoplastics during printing. SIH holds good promise for applications in 3D-printed continuous carbon fiber-reinforced thermoplastic composites, including mold-free forming, complex surface welding, and repair (particularly in narrow and inaccessible areas).

Optimizing the magnetic field strength and concentration of silica coated cobalt ferrite nanoparticles for magnetic hyperthermia

A therapeutic breakthrough in cancer treatment has recently been made by using magnetic nanoparticles (MNPs) for heating in hyperthermia therapy. Unapproachable tumors are being effectively destroyed by focused heat produced by MNPs. The major challenges regarding practical application of this therapy include the control and improvement of induction heating ability of MNPs and hyperthermia temperature range between 42–47 °C, for secure treatment at targeted area. Here, in this study, we have reported the synthesis and characterization of core–shell structured silica-coated cobalt ferrite nanoparticles (SiO2 coated CoFe2O4 MNPs), which are potential candidates for use as heat source in magnetic hyperthermia therapy. The SiO2 coated CoFe2O4 MNPs were synthesized using the reverse micelle method, with the SiO2 coating performed simultaneously during MNP synthesis. Various analytical tools were utilized for the characterization. The structural measurements were probed by X-ray diffraction (XRD). Monodisperse MNPs with nearly spherical core–shell structure was revealed by Transmission electron microscopy (TEM) results. The average diameter of MNPs obtained from TEM analysis was 15 nm. The surface coating of cobalt ferrite MNPs with silica was verified by Fourier transform infrared spectrometry (FTIR). The saturation magnetization values obtained using vibrating sample magnetometer (VSM) measurements were 45.74 emu/g, revealing the superparamagnetic nature of the nanoparticles. The heating efficiency of different concentrations of synthesized nanoparticles was evaluated in an aqueous solution under an alternating magnetic field of strength 5.5 kA/m at a frequency of 260 kHz. A saturation temperature of 42 °C was attained at an optimum concentration of 1.7 mg/mL, while a magnetic field strength of 3.9 kA/m achieved 42 °C at a fixed concentration of 3.5 mg/ml. The obtained specific absorption rate (SAR) values for all the samples were between 56.23 to 100.1 W/g. The correlation between SAR values, MNP concentration, and applied magnetic field strength was also examined. The high saturation magnetization, efficient heating rates, and high SAR values make our synthesized silica-coated cobalt ferrite nanoparticles promising candidates for magnetic hyperthermia treatments, potentially improving therapeutic outcomes for cancer patients.

Fröhlich model characterization of magnetic properties of the induction heating load

Fröhlich model characterization of magnetic properties of the induction heating load

A new accelerated thermal fatigue experiment method of pistons and its application

This study proposed a new test method to take the piston instead of the internal combustion engine as the experimental object and use electromagnetic induction heating and auxiliary cooling to simulate the actual operating conditions of the piston during engine start-stop, to achieve accurate control of the temperature of the heating and cooling cycles. The experimental process can be accelerated by worsening the service conditions. In order to prove the feasibility of this scheme, the temperature field distribution, fatigue life, and failure mode of the piston are compared and analyzed using finite element simulation, theoretical calculation, and surface topography observation. The results show that the error between the simulated temperature value of the key point of the piston and the experimental value of the actual operating condition is less than 5%, the position and value of the maximum temperature of the piston under the thermal fatigue test condition are consistent with the actual engine operating condition, the error between the fatigue life test results and the theoretical calculation results is less than 10%, and the location and cracking mode of the main crack is consistent with the actual working condition. It is proved that the test method is reasonable and feasible, which can provide an important guarantee for the fast and efficient design of high-performance pistons.

Diagnostics of the technical condition of wells drilled through freshwater horizons using active thermometry

Relevance. Recently, ESG (Environment, Social, Governance) principles have been given an important role in the agenda of oil and gas companies – this is an actively developing global trend in the modern business environment. One of its key aspects is a responsible attitude to the environment, increasing the priority of solving environmental problems arising from the extraction of hydrocarbons. A significant environmental problem is, in particular, pollution of freshwater horizons during oil production due to their poor-quality insulation during well cementing. At the same time, in the space of the well behind the casing, there is a flow of borehole fluid to freshwater horizons, which has a negative impact on the environmental situation in this region. In this regard, monitoring the technical condition of wells crossing freshwater horizons is an important and urgent task. Object. An operational well drilled through freshwater horizon, in which geophysical studies are carried out by the method of active thermometry – local heating of the casing section is carried out and the dynamics of the temperature field in it is studied. Aim. To identify qualitative patterns and obtain quantitative estimates of the effect of the fluid flow in the space behind the casing (column space) on the temperature field in the casing. Methods. Numerical mathematical modeling of thermal and hydrodynamic processes in a well using the software package Ansys Fluent (ANSYS Academic Research CFD license, agreement with Bashkir State University dated 06/15/2020). Results. The authors have studied the influence of a plane-parallel horizontal fluid flow of the freshwater horizon on the azimuthal temperature distribution of the casing string during induction heating. It is shown that in the case of leakiness of the cement ring in the interval of the freshwater horizon, an inhomogeneity of the azimuthal temperature distribution of the column is observed, reaching a value of few more K. The authors carried out the simulation of induction heating in the well with liquid column flow to the interval of the freshwater horizon. It is shown that the sign indicating the overflow is the occurrence of a temperature disturbance area vertically above the induction heating interval with a length of more than 1 m. In general, the results of the performed studies show the informativeness of the active thermometry method in relation to the diagnosis of the technical condition of wells drilled through freshwater horizons.