| Only the Electroslag Casting has all these three functions:increase the metal purity, control solidification microstructure and refine the roughcast with near net shaping technology. After Electroslag Remelting (ESR), the ingots have many advantages, such as uniform and compact crystallization tissues, high purity, low sulphur content, less non-metallic inclusion, higher toughness, higher anti-fatigur and weldability property. Every performance index of the casting is significantly better than common casting, and basically meets the forgeability. The products of ESR are used in many ways, involving machinery, chemical industry, transportation, aviation and aerospace, atomic energy, military industry and so on.The paper focuses on electrode, slag, steel fluid and ingots. With the finite element theory, it builds the 3-D finite element calculation model of ESR system model and the model applied with electromagnetic stirring. With finite element analysis software-ANSYS, it programs the composition of electromagnetic and flow field in ESR process. Besides, it exploringly studies the distributions of magnetic induction, electromagnetic force and current density in different process parameters.From the calculated model results in ANSYS, it shows that the distributions of magnetic field and flow field in typical location are in good agreement to the fact. Due to the skin effect, as the current flows from top to bottom, it mostly centralizes on the surface region, and in the radial direction it gradually decreases form external to internal. In the area of steel fluid, the electromagnetic force points to the center, and the value is lower down from two sides to the center. Applied with alternating current of 10kA and 25hz, the maximum electromagnetic force is on the surface. At the center, the value reaches zero. In electrode, steel fluid and ingot, the distribution of the magnetic field is showed as rotation shape. In the slag area, the value of magnetic induction and current density is very little, almost tending to zero. As the frequency increases, the skin effect of the current density's distribution is more and more significant. When the frequency arrives at 35hz, in the center of electrode and ingot, the eddy current is greater than the source, and near the center it generates a small range's reflux whose peak value increases with frequency. Because of the electromagnetic force in ESR system, it forms two symmetric rotating flow near the wall of steel fluid, and its maximum velocity can reaches 0.059 m/s near the slag surface.In the case of magnetic stirring, the paper studies the electromagnetic and fluid distribution of slag area, steel fluid and steel ingot. The result shows:With magnetic stirring machine, in the steel fluid area, it forms rotating electromagnetic force, and its value increases with the frequency; While applied with current 100A and frequency 5hz, magnetic induction can reach 0.026T, and current density can up to 33537A/m2. The maximum force in slag area is 0.45e-10N which can be neglected compared to steel fluid. Applied with magnetic stirring, it forms a rotating flow in fluid steel, and the maximum velocity is 0.20m/s. |
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