Study For Bubbles Behavior Within The Slag In Mold Of Continuous Slab Casting With Argon Blowing

During the continuous casting process,the distribution and migration of argon bubbles in the liquid mold powder affect the flow and heat transfer behavior of the mold powder,thus affecting the quality of the continuous casting slab.In this paper,a 1: 0.6 mold model was established by using a slab continuous casting mold in a domestic steel mil,to study the relationship between the bubble size,the number of bubbles,the bubble velocity,the bubble volume and the emulsification of bubbles,the migration of bubbles in the slag The main conclusions of the paper are concluded as follows:(1)With the increase of the flow rate of argon,the casting speed,the angle of nozzle port,the diameter of the bubbles near the nozzle on the steel-slag interface decreases first and then increases,and the diameter close to the narrow side increases first and then decreases;With the increase of the depth of the immersion nozzle,the diameter of bubbles among areas increase first and then increase.(2)With the increase of the flow rate of argon,the bubble floating speed near the nozzle on the steel-slag interface increases first and then decreases,the bubble floating speed near the narrow side increases.With the increase of the casting speed,the bubble floating speed near the narrow side increases obviously.(3)With the increase of the flow rate of argon,the vicinity of the bubbles into the slag near the nozzle increase,and which close to the narrow side is smal.With the increase of the casting speed,the vicinity of the bubbles into the slag near the narrow side increase and decrease close to the nozzle.(4)There are two kinds of floating modes of argon bubbles in the slag: float in a channel by large bubbles,float free like a curve by small bubbles;the slag floating speed within the flux is far less than that of the molten steel,and it is basically from 0.02m/s to 0.07 m/s.(5)When the flow rate of argon increases from 2L/min to 6L/min,the emulsification of slag is enhanced,with further increase,it will be reduced slightly;the bigger the speed,the more uniform the emulsification of slag is;while the nozzle immersion depths are 160 mm and 240 mm,the emulsion among the mold width is more uniform,and when it is 200 mm,the emulsification of the slag near the nozzle is more serious,which is also serious near the nozzle liquid with the increase of the angle of nozzle port.(6)With the flow rate of argon increasing,the vicinity of the bubbles in the slag rise,which will decrease while the increase of the depth of SEN;The vicinity of the bubbles in the slag enlarge near the nozzle decrease first and then rise close to the narrow side.When the angle of the nozzle port increase from 12° to 15°,the vicinity of the bubbles in the slag enlarge near the nozzle,and it is small when it is to 18°,of which the vicinity is the biggest among the narrow side.