Gray cast iron inoculant

Abstract

A ferrosilicon inoculant for gray cast iron containing between 0.1 to 10% by weight strontium, less than 0.35% by weight calcium, 1.5 to 10% by weight aluminum and 0.1 to 15% zirconium. The inoculant, method for producing the inoculant, method for inoculating the melt and a gray cast iron inoculated with the inoculant are covered.

1 . A ferrosilicon inoculant for cast iron consisting essentially of about 15 to 90% by weight silicon; about 0.1 to 10% by weight strontium; less than about 0.35% by weight calcium; about 1.5 to 10.0% by weight aluminum; about 0.1 to 15% by weight zirconium, and a balance of iron, with residual impurities in the ordinary amount. 
     
     
         2 . The ferrosilicon inoculant according to  claim 1 , wherein the silicon is present in an amount of about 40 to 80% by weight. 
     
     
         3 . The ferrosilicon inoculant according to  claim 1 , wherein the aluminum is present in about 2-6% by weight. 
     
     
         4 . The ferrosilicon inoculant according to  claim 1 , wherein the aluminum is present in about 2-4% by weight. 
     
     
         5 . A method for inoculating gray cast iron comprising adding the ferrosilicon inoculant of  claim 1  to molten cast iron. 
     
     
         6 . The method of  claim 5 , wherein no other inoculant is added to the molten gray cast iron in the transfer ladle. 
     
     
         7 . The method of  claim 5 , wherein no other inoculant is added to the molten gray cast iron in the pouring unit. 
     
     
         8 . The method of  claim 5 , wherein no other inoculant is added to the molten gray cast iron in in the pouring stream to the mold. 
     
     
         9 . The method of  claim 5 , wherein a single addition of the ferrosilicon inoculant of  claim 1  is made to the molten cast iron in the poring unit during the casting process.