Heat transfer and deformation of initial solidification shell in soft contact continuous casting mold under high frequency electromagnetic field were analyzed using numerical simulation method; the relative electromag...Heat transfer and deformation of initial solidification shell in soft contact continuous casting mold under high frequency electromagnetic field were analyzed using numerical simulation method; the relative electromagnetic parameters were obtained from the previous studies. Owing to the induction heating of a high frequency electromagnetic field （20 kHz）, the thickness of initial solidification shell decreases, and the temperature of strand surface and slit copper mold increases when compared with the case without the electromagnetic filed. The viscosity of flux de- creases because of the induction heating of the high frequency electromagnetic field, and the dimension of the flux channel increases with electromagnetic pressure; thus, the deformation behavior of initial solidification shell was different before and after the action of high frequency electromagnetic field. Furthermore, the abatement mechanism of oscillation marks under high frequency electromagnetic field was explained.展开更多
To improve the slab quality, a kind of non-sinusoidal oscillation technique of mold driven by elliptic gears was developed. The waveform functions of non-sinusoidal oscillation were determined, and the calculation met...To improve the slab quality, a kind of non-sinusoidal oscillation technique of mold driven by elliptic gears was developed. The waveform functions of non-sinusoidal oscillation were determined, and the calculation method and curves of technological parameters for non-sinusoidal oscillation were given. At the case of waveform deviation factor a equal to 0.31 and oscillation amplitude h equal to ±2.7 mm, the relationship between oscillation frequency and casting speed is determined, and the technological parameters for non-sinusoidal oscillation are calculated. The testing results of industrial application indicated that this technique could not only improve the Slab surface quality, but also reduce the steel breakout.展开更多
In order to check the general existence of broadening of slab and the reasons of formation,the broadening of slab was investigated on the basis of several industrial manufactures of continuous casting.The results show...In order to check the general existence of broadening of slab and the reasons of formation,the broadening of slab was investigated on the basis of several industrial manufactures of continuous casting.The results show that slab broadening commonly exists in the process of continuous casting.The causes of broadening were ruled out of the consideration of the change of mold size or the change of technical parameters.The results reveal that the broadening of slab probably results from the static pressure of molten steel and the force from driving rolls.At the same time,online observations of three grades of steel in the process of continuous casting reveal that the ratio of ultimate broadening of slab ranges from 1.27% to 3.00%,and even arrives at 4.4%.展开更多
基金Item Sponsored by National Natural Science Foundation of China (59734080)
文摘Heat transfer and deformation of initial solidification shell in soft contact continuous casting mold under high frequency electromagnetic field were analyzed using numerical simulation method; the relative electromagnetic parameters were obtained from the previous studies. Owing to the induction heating of a high frequency electromagnetic field （20 kHz）, the thickness of initial solidification shell decreases, and the temperature of strand surface and slit copper mold increases when compared with the case without the electromagnetic filed. The viscosity of flux de- creases because of the induction heating of the high frequency electromagnetic field, and the dimension of the flux channel increases with electromagnetic pressure; thus, the deformation behavior of initial solidification shell was different before and after the action of high frequency electromagnetic field. Furthermore, the abatement mechanism of oscillation marks under high frequency electromagnetic field was explained.
基金Item Sponsored by National Natural Science Foundation of China(51275446)National Natural Science Foundation of China and Baosteel Group Co.,Ltd.(U1260203)Natural Science Foundation of Hebei Province of China(E2012203080)
文摘To improve the slab quality, a kind of non-sinusoidal oscillation technique of mold driven by elliptic gears was developed. The waveform functions of non-sinusoidal oscillation were determined, and the calculation method and curves of technological parameters for non-sinusoidal oscillation were given. At the case of waveform deviation factor a equal to 0.31 and oscillation amplitude h equal to ±2.7 mm, the relationship between oscillation frequency and casting speed is determined, and the technological parameters for non-sinusoidal oscillation are calculated. The testing results of industrial application indicated that this technique could not only improve the Slab surface quality, but also reduce the steel breakout.
基金Item Sponsored by National Science and Technology Support Program for 11th Five-Year Plan of China(2006BAE03A04)
文摘In order to check the general existence of broadening of slab and the reasons of formation,the broadening of slab was investigated on the basis of several industrial manufactures of continuous casting.The results show that slab broadening commonly exists in the process of continuous casting.The causes of broadening were ruled out of the consideration of the change of mold size or the change of technical parameters.The results reveal that the broadening of slab probably results from the static pressure of molten steel and the force from driving rolls.At the same time,online observations of three grades of steel in the process of continuous casting reveal that the ratio of ultimate broadening of slab ranges from 1.27% to 3.00%,and even arrives at 4.4%.
