Continuous casting equipment for titanium or titanium alloy slab

Abstract

Using plasma arcs generated by plasma torches, the surface of molten metal charged into a mold is heated. EMSs arranged on the lateral sides of the mold are used to stir the surface of the molten metal or the vicinity thereof electromagnetically. Thus, a slab having reduced defects can be cast.

1 . A continuous casting apparatus for charging molten metal constituted of molten titanium or titanium alloy into a bottomless rectangular-shaped mold, solidifying the molten metal therein and drawing out the solidified molten metal, thereby continuously casting a slab formed of titanium or titanium alloy, the continuous casting apparatus comprising:
 a plasma arc heating device configured to heat the surface of the molten metal charged into the mold using plasma arcs; and   at least one electromagnetic stirring device configured to stir the surface of the molten metal or the vicinity of the surface by electromagnetic induction using an alternating current.   
     
     
         2 . A continuous casting apparatus for a slab formed of titanium or titanium alloy according to  claim 1 , wherein
 the electromagnetic stirring device is arranged on a periphery of the mold.   
     
     
         3 . A continuous casting apparatus for a slab formed of titanium or titanium alloy according to  claim 1 , wherein
 the electromagnetic stirring device generates a flow moving parallel to the wall surface of the mold in the surface of the molten metal or in the vicinity of the surface.   
     
     
         4 . A continuous casting apparatus for a slab formed of titanium or titanium alloy according to  claim 3 , wherein
 the electromagnetic stirring device generates a flow turning in the horizontal direction in the surface of the molten metal or in the vicinity of the surface.   
     
     
         5 . A continuous casting apparatus for a slab formed of titanium or titanium alloy according to  claim 1 , wherein
 the electromagnetic stirring device generates a flow colliding with the wall surface of the mold in the surface of the molten metal or in the vicinity of the surface.   
     
     
         6 . A continuous casting apparatus for a slab formed of titanium or titanium alloy according to  claim 5 , wherein
 the electromagnetic stirring device generates a flow moving down along the wall surface of the mold in the molten metal.   
     
     
         7 . A continuous casting apparatus for a slab formed of titanium or titanium alloy according to  claim 5 , wherein
 the electromagnetic stirring device generates a pair of flows turning in the vertical direction and also turning in the mutually opposite directions in the molten metal, to thereby generate a pair of flows respectively colliding with the two opposed wall surfaces of the mold in the surface of the molten metal or in the vicinity of the surface.   
     
     
         8 . A continuous casting apparatus for a slab formed of titanium or titanium alloy according to  claim 6 , wherein:
 the electromagnetic stirring device is arranged over the whole periphery of the mold; and   the electromagnetic stirring device generates a flow moving along all wall surfaces of the mold in the molten metal.   
     
     
         9 . A continuous casting apparatus for a slab formed of titanium or titanium alloy according to  claim 3 , wherein
 the plasma arc heating device heats the surface of the molten metal on the upstream side of the flow in the surface of the molten metal or in the vicinity of the surface.   
     
     
         10 . A continuous casting apparatus for a slab formed of titanium or titanium alloy according to  claim 5 , wherein
 the plasma arc heating device heats the surface of the molten metal on the upstream side of the flow in the surface of the molten metal or in the vicinity of the surface.