A method for the production of cast iron starting from pre-reduced iron ore (DRI) with an electric arc furnace includes the steps of preparing a charge of pre-reduced iron ore DRI having a metallization higher than 90% and containing over 2.8% by weight of carbon, wherein at least 80% of the carbon is combined with the iron to form iron carbide Fe.sub.3C; charging the charge of pre-reduced iron ore into the electric arc furnace; and melting the DRI charge to form liquid cast iron having at least 80% by weight of actual carbon content deriving from the carbon in the charge of pre-reduced iron ore, the melting step being in a reducing atmosphere and in a melting chamber of the electric arc furnace subjected to a positive internal pressure generated by the gases produced by reduction reactions that develop during melting.

A self-lubricating rolling bearing is provided. The chemical compositions in the inner rings and the outer rings of bearing are 3.4-3.7% C, 2.7-2.9% Si, 0.3-0.5% Mn, 0.3-0.5% Cr, ≤0.05% S, ≤0.05% P, 0.03-0.045% Residual Mg, and the remainder Fe. The total percent of the chemical compositions is 100%. The material for the inner and outer rings of the rolling bearing introduced in the invention is austempered ductile iron (ADI). In the microstructure of ADI, the diameter of the graphite nodules is less than 0.02 mm, the number of graphite spheres per square millimeter is more than 400, and the microstructure of the metal matrix in the ADI can be showed clearly only when it is observed on the microscope with a magnification more than 500. Eventually, the self-lubricating rolling bearings are made from the ADI.

A self-lubricating rolling bearing is provided. The chemical compositions in the inner rings and the outer rings of bearing are 3.4-3.7% C, 2.7-2.9% Si, 0.3-0.5% Mn, 0.3-0.5% Cr, ≤0.05% S, ≤0.05% P, 0.03-0.045% Residual Mg, and the remainder Fe. The total percent of the chemical compositions is 100%. The material for the inner and outer rings of the rolling bearing introduced in the invention is austempered ductile iron (ADI). In the microstructure of ADI, the diameter of the graphite nodules is less than 0.02 mm, the number of graphite spheres per square millimeter is more than 400, and the microstructure of the metal matrix in the ADI can be showed clearly only when it is observed on the microscope with a magnification more than 500. Eventually, the self-lubricating rolling bearings are made from the ADI.

An inoculant for the manufacture of cast iron with lamellar, compacted or spheroidal graphite is disclosed. The inoculant has a particulate ferrosilicon alloy having about 40 to 80 wt % silicon, about 0.1 to 10 wt % calcium, 0 and 10% by weight of rare earths, for example cerium and/or lanthanum, and up to 5 wt % aluminium the balance being iron and incidental impurities in the ordinary amount, wherein the inoculant additionally has 0.1 to 10 wt %, based on the total weight of inoculant, antimony oxide where said antimony oxide is in particulate form and is mixed or blended with the ferrosilicon alloy particles, or is simultaneously added to cast iron together with the particulate ferrosilicon alloy particles.

An inoculant for the manufacture of cast iron with lamellar, compacted or spheroidal graphite is disclosed. The inoculant has a particulate ferrosilicon alloy having about 40 to 80 wt % silicon, about 0.1 to 10 wt % calcium, 0 and 10% by weight of rare earths, for example cerium and/or lanthanum, and up to 5 wt % aluminium the balance being iron and incidental impurities in the ordinary amount, wherein the inoculant additionally has 0.1 to 10 wt %, based on the total weight of inoculant, antimony oxide where said antimony oxide is in particulate form and is mixed or blended with the ferrosilicon alloy particles, or is simultaneously added to cast iron together with the particulate ferrosilicon alloy particles.

An end-use casting of a high chromium white iron, i.e. a casting that has been heat-treated, includes a ferrous matrix and Oat least two different chromium carbides dispersed in the matrix, with at least one of the chromium carbides including a transformation product of an as-cast chromium carbide.

An end-use casting of a high chromium white iron, i.e. a casting that has been heat-treated, includes a ferrous matrix and Oat least two different chromium carbides dispersed in the matrix, with at least one of the chromium carbides including a transformation product of an as-cast chromium carbide.

A method for the production of cast iron starting from pre-reduced iron ore (DRI) with an electric arc furnace includes the steps of preparing a charge of pre-reduced iron ore DRI having a metallization higher than 90% and containing over 2.8% by weight of carbon, wherein at least 80% of the carbon is combined with the iron to form iron carbide Fe.sub.3C; charging the charge of pre-reduced iron ore into the electric arc furnace; and melting the DRI charge to form liquid cast iron having at least 80% by weight of actual carbon content deriving from the carbon in the charge of pre-reduced iron ore, the melting step being in a reducing atmosphere and in a melting chamber of the electric arc furnace subjected to a positive internal pressure generated by the gases produced by reduction reactions that develop during melting.

A method for the production of cast iron starting from pre-reduced iron ore (DRI) with an electric arc furnace includes the steps of preparing a charge of pre-reduced iron ore DRI having a metallization higher than 90% and containing over 2.8% by weight of carbon, wherein at least 80% of the carbon is combined with the iron to form iron carbide Fe.sub.3C; charging the charge of pre-reduced iron ore into the electric arc furnace; and melting the DRI charge to form liquid cast iron having at least 80% by weight of actual carbon content deriving from the carbon in the charge of pre-reduced iron ore, the melting step being in a reducing atmosphere and in a melting chamber of the electric arc furnace subjected to a positive internal pressure generated by the gases produced by reduction reactions that develop during melting.

An inoculant for manufacturing cast iron with lamellar, compacted or spheroidal graphite is disclosed. The inoculant has a particulate ferrosilicon alloy having 40 and 80% by weight of silicon, 0.5-5 wt % of calcium and/or strontium and/or barium, 0-10 wt % of rare earths, 0-5 wt % of magnesium, less than 5% by weight of aluminium, 0-10 wt % of manganese and/or zirconium, and the balance being iron, wherein the inoculant additionally contains 0.1-10 wt % of particulate bismuth oxide particles and optionally 0.1-10 wt % of one or more particulate metal sulphides and/or one or more particulate iron oxides, where the particulate bismuth oxide is mixed or blended with the ferrosilicon particles, or is simultaneously added to cast iron together with the particulate ferrosilicon particles.