Inoculating mixture containing bismuth and rare earth metals for treatment of molten iron during fab

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 %.