Method for production of ductile iron

Abstract

The present invention relates to a method for nodularizing treatment of ductile iron using a ladle treatment method for nodularizing of a magnesium ferrosilicon alloy, where a magnesium ferrosilicon nodularizing alloy consisting essentially of 40 to 80% by weight of silicon, 2 to 15% by weight of magnesium, 0.3 to 5% by weight of lanthanum, 0 to 6% by weight of calcium, 0 to 5% by weight of aluminum, the balance being iron, is added to the ladle whereafter the molten iron is supplied to the ladle.

1 . Method for nodularizing treatment of ductile iron using a ladle treatment method for introduction of a magnesium ferrosilicon alloy, characterized in that a magnesium ferrosilicon nodularizing alloy consisting essentially of 40 to 80% by weight of silicon, 2 to 15% by weight of magnesium, 0.3 to 5% by weight of tanthanum, 0 to 6% by weight of calcium, 0 to 5% by weight of aluminum, the balance being iron, is added to the ladle whereafter the molten iron is supplied to the ladle.  
     
     
         2 . Method according to  claim 1 , characterized in that the magnesium ferrosilicon alloy added to the ladle comprises 0.5 to 1.5% by weight of lanthanum.  
     
     
         3 . Use of a magnesium ferrosilicon alloy comprising 40 to 80% by weight of silicon, 2 to 15% by weight of magnesium, 0.3 to 5% by weight of lanthanum, 0 to 6% by weight of calcium, 0 to 5% by weight of aluminum, the balance being iron, as nodularizer in the ladle treatment method for the production of ductile cast iron.