-
In the electromagnetic levitation experiment, the liquid flow in the undercooled liquid alloy remarkably affects the relevant thermodynamic property measurement and solidification microstructure. Therefore, it is of great importance to understand the fluid convection inside the undercooled melt. Theoretical calculation and electromagnetic levitation experiment have been used to investigate the internal velocity distribution and rapid solidification mechanism of Fe50Cu50 alloy. Based on axisymmetric electromagnetic levitation model, the distribution patterns of magnetic flux density and inducted current for levitated Fe50Cu50 alloy are calculated together with the mean Lorenz force. The Navier-Stokes equations are further taken into account in order to clarify the internal fluid flow. The results of the theoretical calculation reveal that the fluid velocity within levitated melt is strongly dependent on three factors, i.e., current density, current frequency and melt undercooling. As one of these factors increases, the maximum fluid velocity decreases while the average fluid velocity increases. Meanwhile, the area with fluid velocity larger than 100 mm·-1 is significantly extended. Furthermore, the fluid flow within levitated melt displays an annular tubular distribution characteristic. The Fe50Cu50 alloy melt is undercooled and solidified under electromagnetic levitation condition. In this undercooling regime △ T50Cu50 alloy melt has suppressed phase separation substantially. Once the undercooling attains a value of 150 K, metastable phase separation leads to the formation of layered pattern structure consisting of floating Fe-rich zone and sinking Cu-rich zone. A core-shell macrosegregation morphology with the Cu-rich zone distributed in the center and outside of the sample and Fe-rich zone in the middle occurs if the undercooling increases to 204 K. With the enhancement of undercooling after phase separation, the grain size of α -Fe dendrites in Cu-rich zone presents a decreasing trend. In contrast to the phase separated morphology of Fe50Cu50 alloy under the glass fluxing condition, the phase separated morphologies show obviously different characteristics. In such a case, the forced convection induced by electromagnetic stirring results in the formation of wavy interface between Fe-rich and Cu-rich zones, the distorted morphology of the Cu-rich spheres distributed in the Fe-rich zone, and the increased appearance probabilities of Cu-rich spheres at the upper part of electromagnetically levitated sample. Experimental observations demonstrate that the distribution pattern of Cu-rich spheres in Fe-rich zone is influenced by the tubular fluid flow inside the melt.
-
Keywords:
- electromagnetic levitation /
- forced convection /
- high undercooling /
- phase separation
[1] Seidel A, Soellner W, Stenzel C 2011 4th International Symposium on Physical Sciences in Space Bonn, Germany, July 11-15, 2011 p1
[2] Daun K J 2016 Metall. Mater. Trans. A 47 3300
[3] Chang J, Wang H P, Zhou K, Wei B 2012 Appl. Phys. A 109 139
[4] Ma W Z, Ji C C, Li J G 2002 Acta Phys. Sin. 51 2233 (in Chinese)[马伟增, 季诚昌, 李建国 2002 物理学报 51 2233]
[5] Wang H P, Chang J, Wei B 2009 J. Appl. Phys. 106 033506
[6] Brillo J, Lohofer G, Schmidt-Hohagen F, Schneider S, Egry I 2006 Int. J. Mater. Prod. Tec. 26 247
[7] Zhang L B, Dai F P, Xiong Y Y, Wei B B 2005 Acta Phys. Sin. 54 419 (in Chinese)[张蜡宝, 代富平, 熊予莹, 魏炳波 2005 物理学报 54 419]
[8] Lu X Y, Cao C D, Kolbe M, Wei B, Herlach D M 2005 Meas. Sci. Technol. 16 394
[9] Sneyd A, Moffatt H 1982 J. Fluid. Mech. 117 45
[10] Okress E, Wroughton D, Comenetz G, Brace P, Kelly J 1952 J. Appl. Phys. 23 545
[11] Spitans S, Jakovics A, Baake E, Nacke B 2013 Metall. Mater. Trans. B 44 593
[12] Dughiero F, Baake E, Forzan M, Bojarevics V, Roy A, Pericleous K 2011 Compel. 30 1455
[13] Feng L, Shi W Y 2015 Metall. Mater. Trans. B 46 1895
[14] Menter F R 1994 AIAA J. 32 8
[15] Cho Y C, Kim B S, Yoo H, Kim J Y, Lee S, Lee Y H, Lee G W, Jeong S Y 2014 Cryst. Eng. Comm. 16 7575
[16] Lee G W, Jeon S, Kang D H 2013 Cryst. Growth. Des. 13 1786
[17] Gntherodt H J, Hauser E, Knzi H, Mller R 1975 Phys. Lett. 54 291
[18] Gale W F, Totemeier T C 2004 Smithells Metals Reference Book (Vol. 8) (Netherlands:Elsevier Butterworth-Heinemann) P14-1-P14-29
[19] Munitz A, Venkert A, Landau P, Kaufman M J, Abbaschian R 2012 J. Mater. Sci. 47 7955
[20] Luo S B, Wang W L, Chang J, Xia Z C, Wei B 2014 Acta Mater. 69 355
[21] Zhao J Z, Li H L, Zhao L 2009 Acta Metall. Sin. 45 1435
-
[1] Seidel A, Soellner W, Stenzel C 2011 4th International Symposium on Physical Sciences in Space Bonn, Germany, July 11-15, 2011 p1
[2] Daun K J 2016 Metall. Mater. Trans. A 47 3300
[3] Chang J, Wang H P, Zhou K, Wei B 2012 Appl. Phys. A 109 139
[4] Ma W Z, Ji C C, Li J G 2002 Acta Phys. Sin. 51 2233 (in Chinese)[马伟增, 季诚昌, 李建国 2002 物理学报 51 2233]
[5] Wang H P, Chang J, Wei B 2009 J. Appl. Phys. 106 033506
[6] Brillo J, Lohofer G, Schmidt-Hohagen F, Schneider S, Egry I 2006 Int. J. Mater. Prod. Tec. 26 247
[7] Zhang L B, Dai F P, Xiong Y Y, Wei B B 2005 Acta Phys. Sin. 54 419 (in Chinese)[张蜡宝, 代富平, 熊予莹, 魏炳波 2005 物理学报 54 419]
[8] Lu X Y, Cao C D, Kolbe M, Wei B, Herlach D M 2005 Meas. Sci. Technol. 16 394
[9] Sneyd A, Moffatt H 1982 J. Fluid. Mech. 117 45
[10] Okress E, Wroughton D, Comenetz G, Brace P, Kelly J 1952 J. Appl. Phys. 23 545
[11] Spitans S, Jakovics A, Baake E, Nacke B 2013 Metall. Mater. Trans. B 44 593
[12] Dughiero F, Baake E, Forzan M, Bojarevics V, Roy A, Pericleous K 2011 Compel. 30 1455
[13] Feng L, Shi W Y 2015 Metall. Mater. Trans. B 46 1895
[14] Menter F R 1994 AIAA J. 32 8
[15] Cho Y C, Kim B S, Yoo H, Kim J Y, Lee S, Lee Y H, Lee G W, Jeong S Y 2014 Cryst. Eng. Comm. 16 7575
[16] Lee G W, Jeon S, Kang D H 2013 Cryst. Growth. Des. 13 1786
[17] Gntherodt H J, Hauser E, Knzi H, Mller R 1975 Phys. Lett. 54 291
[18] Gale W F, Totemeier T C 2004 Smithells Metals Reference Book (Vol. 8) (Netherlands:Elsevier Butterworth-Heinemann) P14-1-P14-29
[19] Munitz A, Venkert A, Landau P, Kaufman M J, Abbaschian R 2012 J. Mater. Sci. 47 7955
[20] Luo S B, Wang W L, Chang J, Xia Z C, Wei B 2014 Acta Mater. 69 355
[21] Zhao J Z, Li H L, Zhao L 2009 Acta Metall. Sin. 45 1435
Catalog
Metrics
- Abstract views: 6220
- PDF Downloads: 195
- Cited By: 0
下载:
