| As the growing and maturating, continuous casting technology is developing toward final shape, high speed, and high quality. Oscillation marks are drawn more and more attention for it's the main reason of the forming of cracks and segregation in strand's surface. The urgent problem must be solved is how to lighten or eliminate the oscillation marks on strand's surface. Electromagnetic soft contact continuous casting technology is become one of the research hotspots of continuous casting technology in recent years due to it's outstanding performance to enable the product quality with no surface defects (e.g. no oscillation marks, no cracks and so on) and the casting speed to be enhanced. However, whether electromagnetic soft contact continuous casting technology can be used in practice, the key is the mold's cooling and magnetism effect. This is also the bottleneck of soft contact continuous casting technology for its industrialization.Based on electromagnetism theory, a physical and mathematical model of electromagnetic continuous casting was developed through finite element methods. The distribution of magnetic induction density (B) in the coil was measured. By comparing the measured value with the calculated results, the validity of calculating the electromagnetic field through the model was proved. The structure parameter of the coil was modified.Three-dimensional numerical simulations on magnetic field in electromagnetic soft-contact continuous casting model were carried out through the finite element software ANSYS. The effects of molten steel level in mold on the distributions of magnetic field and electromagnetic force were analyzed. The effects of mold's structure parameter, induction current power and frequency, the amount of coil circles on the distributions of B. The results show that the distribution of magnetic induction density, B, is mainly distributed at the profile-surface of liquid steel. If the liquid steel level is blow the coil top, the maximum value of B is near the top surface of liquid steel and falls gradually along the withdrawing direction. If the liquid steel level is above the coil top, the maximum value of B is moving toward the centre of the coil as the liquid steel level is rising. The distributing character of electromagnetic body force is mostly consistent with that of B. The liquid steel level should be controlled near the coil top. The better number of mold slits is 16, the better width of the slits is about 1 mm, along the slits length scope should be full distributed with the coil. The better frequency of the induction current is 20 kHz. The power of the induction current should be in a reasonable range, because both uniformity of B distribution and stability of molten steel meniscus should be considered.High frequency electromagnetic field have induction heating effect to the molten steel as the same time as soft-contact is achieved, and have significant effect on temperature field of molten steel, change the location of initial solidification point and the thickness of initial solidification shell. So, in this research, induction heating effect on initial solidification shell in electromagnetic soft-contact continuous casting mold were carried out though coupling electromagnetic field, flow field and temperature field. The results show that the thickness of initial solidification shell is decreased own to the induction heating, and the induction heating is focusing on the top of the strand. The larger the casting speed is, the smaller the effect of high frequency electromagnetic field is. The slit has little effect on the uniformity of temperature distribution along the strand's circumference. The thickness of initial solidification shell is also decreased as the width of slit is increased. With the increment of slit number, intensity of the induction heating is increasing and acting range is expanding.
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