Inoculating mixture containing bismuth and rare earth metals for treatment of molten iron during fabrication of thin iron components

摘要

Inoculating mixture for the treatment of molten iron is made up of 5 to 75 % of an A type ferrosilicon alloy and 25 to 95 % of a type B silicon or ferrosilicon alloy. The type A alloy has a Si/Fe ratio of greater than 2 and contains 0.005 to 3 % of rare earth metal, 0.005 to 3 % of bismuth, lead and/or antimony and at least 3% of calcium, with a (Bi+Pb+Sb)/TR ratio of between 0.9 and 2.2. The type B alloy has a Si/Fe ratio of greater than 2 and contains a calcium content such that the total calcium content of the mixture may be between 0.3 and 3 %.