Induction Heating Process Research Articles

Effect of Repeated Induction Heating on Fatigue Crack Propagation in SAE 52100 Bearing Steel

Martensitic high carbon high strength SAE 52100 bearing steel is one of the main alloys used for rolling contact applications when high wear and fatigue resistance are required. Refining the microstructure of steel improves its mechanical properties (e.g. toughness). In this work SAE 52100 specimens were exposed to repeated induction heating process and rotation bending tests were performed using single- and repeatedly heat-treated material in order to investigate the influence of this cyclic heat treatment on the mechanical properties of SAE 52100. In an attempt to determine the effect of the repeated induction heating and quenching on the material, we focused our observations on the internal fatigue “fisheye" cracks. It was noted that crack propagation was successfully halted by the refined microstructure in heat affected zone, therefore it can be concluded that repeated induction heating and quenching processes help to slow down the propagation of fisheye cracks in SAE52100 steel bars.

Prediction of heating-line paths in induction heating process using the artificial neural network

This paper presents the development of a back propagation neural network model for the prediction of heating-line positions in induction heating process. The vertical displacements of plate have been considered as the input parameters and the selected induction heating lines as output parameters to develop the model. The training patterns of neural network are obtained using an analytical solution that predicts plate deformations in induction heating process. The feasibility test reveals that the developed method can be used to determine the heating-line positions in line heating process.

Influence of workpiece height on the induction heating process

A set of 2D steady state finite element numerical simulations of electromagnetic fields, eddy currents distribution and induction heating pattern was performed for different heights of a metal workpiece. Comparison between the calculation results show the height of the workpiece body with respect to the induction coil has a marked effect on the electromagnetic field distribution, eddy currents profile, heating structure and coil efficiency in the system. If the workpiece height is equal to or less than the coil height, then overheating at the workpiece ends is high and makes a nonuniform heating pattern along the workpiece wall.

MODELLING OF INDUCTION HEATING OF EXTRUDER BARREL DURING MANUFACTURING EXPANDED POLYSTYRENE SLABS

The mathematical models of the process of indirect induction heating of granulated polystyrene in extruder during manifacturing of expanded polystyrene slabs are viewed. The proposed models are used to design energy-efficient construction of induction heaters in extrusion- type line for the production of expanded polystyrene slabs.

磁性金属における誘導加熱過程の計算法

磁性金属における誘導加熱過程の計算法

Numerical Simulation of Induction Heating for Crankshaft

This paper describes the three-dimensional modeling of an induction heating processing for crankshaft. To realize the suitable processing parameters of induction heating, magneto-thermal coupled analysis of eddy currents and heat conduction have been carried out by using the finite element method. The dependence of material properties on temperature is taken into account in numerical simulation. Influences of induction heating parameters on eddy current and temperature are identified. The transient temperature field of heated crankshaft is obtained. The simulation results can offer a reference in determining processing parameters.

Numerical study of induction heating in melt growth systems—Frequency selection

A set of 2D finite element numerical simulation of induction heating process for an oxide Czochralski crystal growth system has been made for a range of f=1–100 kHz applied frequency of driving current. It was shown that the frequency selection has a marked effect in all basic induction phenomena, including electromagnetic field distribution, skin depth, coil efficiency, and intensity and structure of heating in the growth setup.

Simulations and measurements of combined induction heating and extrusion processes

The manufacturing process chain at glass-lubricated extrusion of stainless steel tubing is simulated using the finite element method. The developed model includes sub-models of induction heating, expansion and extrusion. An in-house mapping tool is used to transfer the temperature fields between the electromagnetic-thermal and thermo-mechanical analyses. Using the combined model it is possible to study the influence of different process parameters on the temperature distribution in the billet, and how this affects the final extrusion properties. In this study, the model is applied to two cases of tube extrusion, one using an austenitic stainless steel and one using a duplex, austenitic/ferritic, stainless steel. It is shown that the induction heating model successfully predicts the temperatures obtained experimentally from thermocouples placed in the steel billets during heating. The agreement between models and experiments regarding extrusion force and expansion force is satisfactory.

급속소결에 의해 제조된 Al2O3/Fe-Ni 나노복합재료의 미세조직 및 기계적 특성

A new High Frequency Induction Heating (HFIH) process has been developed to fabricate dense <TEX>$Al_2O_3$</TEX> reinforced with Fe-Ni magnetic metal dispersion particles. The process is based on the reduction of metal oxide particles immediately prior to sintering. The synthesized <TEX>$Al_2O_3$</TEX>/Fe-Ni nanocomposite powders were formed directly from the selective reduction of metal oxide powders, such as NiO and <TEX>$Fe_2O_3$</TEX>. Dense <TEX>$Al_2O_3$</TEX>/Fe-Ni nanocomposite was fabricated using the HFIH method with an extremely high heating rate of <TEX>$2000^{\circ}C/min$</TEX>. Phase identification and microstructure of nanocomposite powders and sintered specimens were determined by X-ray diffraction and SEM and TEM, respectively. Vickers hardness experiment were performed to investigate the mechanical properties of the <TEX>$Al_2O_3$</TEX>/Fe-Ni nanocomposite.

고주파유도 급속 금형가열 과정의 3차원 유한요소해석

Abstract Rapid mold heating has been recent issue to enable the injection molding of thin-walled parts or micro/nano structures. High-frequency induction is an efficient way to heat mold surface by electromagnetic induction in a non-contact manner, and has been recently applied to the injection molding due to its capability of rapid heating and cooling of mold surface. The present study covers a three-dimensional finite element analysis to investigate heating efficiency and structural safety of the induction heating process of an injection mold. To simulate the induction heating process, an integrated simulation method is proposed by effectively connecting an electromagnetic field analysis, a transient heat transfer analysis and a thermal stress analysis. The estimated temperature changes are compared with experimental measurements for various types of induction coil, from which heating efficiency according to the coil shape is discussed. The resulting thermal stress distributions of the mold plate for various types of induction coils are also evaluated and discussed in terms of the structural safety.

Numerical analysis and thermographic investigation of induction heating

Induction heating process was investigated numerically and experimentally. Cylindrically shaped steel workpiece was heated with different heating protocols. Numerical model with coupled electromagnetic and thermal physical phenomena was solved using the finite element method. Temperature-dependent and temperature-independent steel material properties were considered and their impact on simulation results was evaluated. Simulation results were also compared with experimental measurements using an algorithm for processing thermographic images. Good agreement between them was obtained for workpieces without defects. With ability to observe temperature distributions and material defects, the thermographic camera demonstrated to be an effective non-contact measurement tool and suitable alternative to thermocouples.

INDUCTION SINTERING OF %3 Cu CONTENTED IRON BASED POWDER METAL PARTS

In this study; iron powder metals were sintered with induction heating process. Sintering process has been achieved with an induction generator that has 12 kW power supply and 30 kHz frequency. ASC10029 grade iron powder was mixed with copper with a ratio of %3 and zinc stearat with a ratio of %0.8 of iron mass by weight. Several duration in the range of 1, 2 and 3 minutes was studied during induction sintering. Transverse rupture strength, hardness and micro structural investigations were done. Obtained mechanical properties and microstructures were compared with traditionally sintered samples. At the end of the induction sintering process for a period of 3 minutes, the maximum stress values that were gotten from classically oven-sintered samples for a period of 30 minutes are reached.

Computational Study of Electromagnetic Fields, Eddy Currents and Induction Heating in Thin and Thick Workpieces

A set of 2D steady state finite element numerical simulations of electromagnetic fields, eddy currents distribution and induction heating pattern has been done for different thicknesses of ametal workpiece. Comparison between the calculation results show the importance of workpiece thickness on induction heating process including electromagnetic field distribution, eddy currents pattern, heating structure and coil efficiency. PACS: 02.60.Cb, 02.70.Dh, 07.05.Tp, 81.05.Bx

Numerical Simulation of Temperature Field in Barrel of Injection Molding Machine during Induction Heating Process Based on ANSYS Software

A finite element model of temperature field coupled with electromagnetic field has been established based on induction heating theory including Maxwell’s equations, thermal conductivity differential equation and magnetic vector potential to simulate the induction heating process of barrel of injection molding machine by universal ANSYS software, and to obtain temperature field of the barrel related to time variation. The coupled thermal and electromagnetic field problem taking account of nonlinear materials characteristics related to temperature was discussed. The induction heating process of barrel was analyzed, and the temperature distribution and its variation with time were obtained.

Influence of crucible geometry and position on the induction heating process in crystal growth systems

A series of 2D finite element numerical simulations of induction heating process for an oxide Czochralski crystal growth system has been done for different shapes and locations of a metal crucible. Comparison between the computational results shows the importance of crucible shape, geometry and its position with respect to the RF-coil on the electromagnetic field and heat generation distribution in the growth setup.

Analysis of Bending Deformation in Triangle Heating of Steel Plates with Induction Heating Process Using Laminated Plate Theory#

The steel-forming process in shipyards is considered an important stage with respect to productivity and precision of curved plates. The induction heating process has been of interest to steel formation because the power and its distribution are easier to control and reproduce. Besides, induction heating equipment can be easily integrated with a robotic system for automation. The heating process usually utilizes line heating or triangle heating methods to form hull plates. Even though a number of studies on the line heating method have been performed, there have been few studies on the triangle heating method. In this study, using a simplified elasto-plastic model and laminated plate theory, an analytic means of predicting the bending deformation in triangle heating of steel plates is derived. For the purpose of this, the induction heating process is modeled in advance, with numerical heat flux and heat flow analyses to determine the plastic region. The plastic region is considered as an inclusion that has eigenstrains in the laminated plate. The analytic solution is applied to predict deformations to verify its exactness. The results of the analytic solution are quite good compared with those of the triangle heating experiment, revealing the effectiveness of the analytic solution.

The Development of an Artificial Neural Network Model to Predict Heating-Line Positions for Plate Forming in Induction Heating Process#

An artificial neural network model can help manufacturers determine the positions of induction heating lines and their heating parameters to form a desired shape of plate. The vertical displacements of a deformed plate are considered as the input parameters and the selected induction heating lines as output parameters to develop the model. The training patterns of neural network are obtained using an analytical solution that is derived from the plate theory to predict plate deformations in induction heating process. The plastic region in the analytical solution of the angular deformation of a steel plate is obtained from the thermal analysis of the plate with the heat input calculated from the electro-magnetic analysis of the induction heating process.

Prediction of deformations of steel plate by artificial neural network in forming process with induction heating

To control a heat source easily in the forming process of steel plate with heating, the electro-magnetic induction process has been used as a substitute of the flame heating process. However, only few studies have analyzed the deformation of a workpiece in the induction heating process by using a mathematical model. This is mainly due to the difficulty of modeling the heat flux from the inductor traveling on the conductive plate during the induction process. In this study, the heat flux distribution over a steel plate during the induction process is first analyzed by a numerical method with the assumption that the process is in a quasi-stationary state around the inductor and also that the heat flux itself greatly depends on the temperature of the workpiece. With the heat flux, heat flow and thermo-mechanical analyses on the plate to obtain deformations during the heating process are then performed with a commercial FEM program for 34 combinations of heating parameters. An artificial neural network is proposed to build a simplified relationship between deformations and heating parameters that can be easily utilized to predict deformations of steel plate with a wide range of heating parameters in the heating process. After its architecture is optimized, the artificial neural network is trained with the deformations obtained from the FEM analyses as outputs and the related heating parameters as inputs. The predicted outputs from the neural network are compared with those of the experiments and the numerical results. They are in good agreement.

Simplified Approach for 3-D Nonlinear Induction Heating Problems

The paper presents a two-stage approach to solve a class of nonlinear 3-D eddy current problems with high saturation, typical of induction heating processes. The proposed method separates the problem of heavy nonlinearity from the complexity of the geometry, by resorting to a 1-D fast nonlinear solver which is coupled with a linear 3-D solver. Under certain hypotheses on the geometry, the approach is shown to be effective and accurate. Comparison with a commercial 3-D nonlinear code are provided.

Compression of the Radiative Heat Transfer BEM Matrix of an Inductive Heating System Using a Block-Oriented Wavelet Transform

Inductive heating processes become more and more important, and therefore the interest in thermal effects of an inductive heating system increases. Radiative heat transfers are normally neglected even though these transfers affect the temperature of the inductive heating system up to ten percent. To compute radiative heat transfers a boundary element method (BEM) is of first choice, due to a surface-to-surface heat transfer. To counteract the general disadvantage of a BEM-the quadratic growth of the system matrix-an application is presented using an adapted version of the JPEG2000 standard, a file format for compressing graphic images. Furthermore, an arbitrary number N of degree of freedom (DOF) can be used to set up the BEM system matrix, while an adapted block-oriented fast wavelet transform compresses the preponderant populated BEM system matrix. Finally, the BEM system of linear equations is solved at compressed state using a normal iterative solver with nearly the same number of iterative steps as in uncompressed state.