46 10 () Vol.46 No.10 2015 10 Journal of Central South University (Science and Technology) Oct. 2015 DOI: 10.11817/j.issn.1672-7207.2015.10.004 ( 110819) () TP391 A 1672 7207(2015)10 3580 06 Electromagnetic behavior for laboratory scale and industrial scale electroslag remelting process LIU Fubin, LI Yongwang, JIANG Zhouhua, LI Huabing, GENG Xin, CHEN Xu (School of Materials and Metallurgy, Northeastern University, Shenyang 110819, China) Abstract: The electromagnetic phenomena occurring in the electroslag remelting (ESR) have a significant influence on the performance and the quality of ingot product. The electromagnetic phenomena (current density, magnetic field intensity, electromagnetic force and Joule heating) of ESR system were described by numerical simulation. Moreover, the model was verified according to the magnetic field intensity measured results reported. There is a good agreement between the calculated results and the measured results in slag bath. The results show that the skin effect is remarkable in industrial scale ESR system. The current density at electrode surface increases with the increase of working current frequency. Furthermore, the characteristic of current density distribution, magnetic field intensity, electromagnetic force and Joule heating in the slag bath during laboratory scale and industrial scale ESR process were analyzed. Key words: electroslag remelting (ESR); electromagnetic field; Lorentz force; numerical simulation [1] 2015 03 202015 05 26 (Foundation item)(51204041)(863 )(2012AA03A502) (LT20120008)(Project (51204041) supported by the National Natural Science Foundation of China; Project (2012AA03A502) supported by the National High Technology Research and Development Program of China (863 Program); Project (LT20120008) supported by Innovative Research Team in University of Liaoning Province) E-mailliufb@smm.neu.edu.cn
10 3581 [2 12] Dilwari [2 3] Maxwell [6] Jardy [7 8] Li [9] Maxwell ANSYS 1 1.1 Maxwell [2] 1) 2) [7] 3) [7] 4) 1 Maxwell 1) Faraday B E (1) t 2) Ampere H J (2) B 0 (3) J 0 (4) E V/mB T H A/m J A/m 2 t, s F JB J H (5) Lorentz 0 J J QJoule (6) μ 0 H/mσ Ω m Maxwell 2 1 Hˆ Hˆ r j ˆ 2 0H r r r z Ĥ H θ ω j 1 (7)(2) J ˆ Jˆ r z Hˆ z 1 ( rhˆ ) r r J ˆr J ˆz J r J z (5) 2π / 1 * F ˆ ˆ r 0 Re( H Jz) 2 (9) 1 ˆ ˆ* Fz 0 Re( H Jr) 2 Re Jˆr * Jˆz * J ˆr J ˆz Q Joule * * 1 Jˆ ˆ ˆ ˆ Re rjr JzJ z 2 sl( T ) (7) (8) (10) (ANSYS solid97 ) () 0 V 1.2 ( 1) [13] 1(a) (b) [6] 50%CaF 2 30%Al 2 O 3 20%CaO M2
3582 () 46 40%~60% CaF 2 10%~20% CaO20%~30% Al 2 O 3 10%, SiO 2 5% MgO() Cr5 1 2 (r=60 mm) Fig. 2 Comparison of predicted and measured value of magnetic field intensity (a) (b) 1 Fig. 1 Finite element model of electroslag remelting 1 Table 1 Parameters of model [6] /mm 40 350 ()/ (mmmm) 700.1 4750.7 /mm 80 180 /mm 5 20 /( ) 37 0 /ka 26 22 /Hz 50 5, 25, 40, 50, 60 /(kω 1 m 1 ) 2.22 8.33 /(kω 1 m 1 ) 1.18 1.40 /(MH m 1 ) 1.26 1.26, (CT3 ) [6] 2.2 3 f=50 Hz / 0 V 4 f=50 Hz 4 2 2.1 2 2.6 ka 50 Hz (r=60 mm) 2 /(z=0) (a) (b) 3 Fig. 3 Distribution of electric potential in ESR
10 3583 (a) (b) 4 Fig. 4 Distribution of current density of ESR 4(a) 1/ πf 0 0.077 m 3 m ( 4(b)) 5 5 5 Hz 60 Hz 60 ka/m 2 140 ka/m 2 2.3 6 f=50 Hz 6 (a) (z=1 m)(b) (z=0.5 m) /Hz15225340450560 5 Fig. 5 Current density distribution of industrial scale ESR (a) (b) 6 Fig. 6 Distribution of magnetic field intensity in ESR 7 f=50 Hz 7 (r=0.35 m) (r=0.475 m)
3584 () 46 9 / 9 / x / 1z=0.88 m()2z=0.88 m(/) 3z=0.84 m()4z=0.70 m(/) 5z=0.68 m() 7 Fig. 7 Distribution of magnetic field intensity along radius at different axial locations in industrial scale ESR process 7.366 ka/m(7.37 ka/m) Patel [14] 2.4 8 f=50 Hz 8 (a) (b) 8 Fig. 8 Distribution of Lorentz force in ESR /Hz15225340450560 9 / Fig. 9 Effect of frequency on Lorentz force distribution of slag-metal interface in industrial scale ESR 10 f=50 Hz 10 10(a) (b) 90.4 MW/m 3 12.3 MW/m 3 () () ( 4) ( 10)
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