A multiple chamber material-stirring lance and method used to treat molten metal in a ladle, the lance having a stirring gas chamber, and a plurality of gas permeable ports arranged at a terminal end of the gas chamber, and at least one material chamber positioned parallel to the gas chamber and terminating in a plurality of material ports. In use, the multiple chamber material-stirring lance is lowered into the ladle of molten metal, and gas and material are both introduced into a respective chamber and emitted through their respective ports. Stirring gas emitted through the gas permeable ports under a gas pressure between 40 and 600 cfm causes the stirring gas to create a boiling effect in the molten metal, drawing material into the stirring gas bubbles and away from the lance body, improving material dispersion efficiency and thus impurity extraction from the molten metal.

Methods and compositions for producing reduced carbon footprint steel compositions by providing a molten steel having a carbon content; and introducing a carbon containing agent into the molten steel. At least a portion of the carbon containing agent is a reclaimed olefin coke.

A steel for induction hardening according to the present invention includes a chemical composition consisting of, in mass percent: C: 0.58 to 0.68%, Si: 0.70 to 1.40%, Mn: 0.20 to 1.40%, P: less than 0.020%, S: less than 0.020%, Al: 0.005 to 0.060%, N: 0.0020 to 0.0080%, 0: 0.0015% or less, V: 0.01 to 0.25%, B: 0.0003 to 0.0040%, Ti: 0.010 to 0.050%, and Ca: 0.0005 to 0.005%, with the balance being Fe and impurities, and satisfies Formulae (1) to (3). The steel microstructure is made up of ferrite and pearlite. A ratio of a number of composite inclusions is 20% or more.

C+Si/7+Mn/5+Cr/9+Mo/2.51.05 (1)

C+Si/10+Mn/20+Cr/250.70 (2)

Cr/Si0.20 (3)

A method for desulfurizing molten steel comprising taking a sample out from molten steel after tapping from a converter or during secondary refining and analyzing the sample rapidly with high accuracy by a method comprising a high frequency induction heating step wherein the sample is combusted and oxidized under the high frequency induction heating in an oxygen atmosphere having an oxygen purity of 99.5 vol % or more to convert S in the sample into SO.sub.2 and an analyzing step wherein SO.sub.2-containing gas produced in the high frequency induction heating step is analyzed through an ultraviolet fluorescence method to quantify S concentration of the sample.

The invention relates to a method for producing ductile iron alloys and products thereof, and in particular ductile iron alloys with at least a partial pearlitic structure. The inventors have sought to develop an improved iron alloy for providing vehicle parts, in particular disc brake rotors. The method for producing a ductile iron alloy comprises the steps of: heating a steel composition in a furnace to produce a molten steel; transferring said molten steel to an inoculation ladle; inoculating said molten steel with an inoculant for a predetermined inoculation time to produce an inoculated molten steel; and pouring said inoculated molten steel into a mould to produce a ductile iron alloy with at least a partial pearlitic structure.

A coaxial material-stirring lance (40) and method used to treat molten metal in a ladle, the lance having a stirring gas chamber (48), and a plurality of gas permeable ports (50 52) arranged as upper and lower port arrays along a length of the gas chamber, and at least one material chamber (43) positioned inside and coaxial with the gas chamber and terminating in at least one material ports (60). In another embodiment, a second material chamber is included inside the gas chamber, parallel to and immediately adjacent the material chamber. In use, the coaxial material-stirring lance is lowered into the ladle of molten metal, and gas and material are both introduced into a respective chamber. Gas mixes material through the molten metal, causing impurities to be removed from the metal.

Embodiments include a method of making steel with low carbon content which includes preparing a heat of molten steel composition in a steelmaking furnace to a tapping temperature ranging from 2912 to 3060 degrees F. and tapping into a ladle the molten steel composition having an oxygen level is about 700 to 1000 ppm. The molten steel composition is then transported to a ladle metallurgy furnace, where the molten steel composition is further heated and one or more elements are added to the molten steel composition. The molten steel composition is then transported from the ladle metallurgy furnace to a vacuum tank degasser. The molten steel composition is then decarburized and one or more elements are added to the molten steel composition at the vacuum tank degasser for deoxidization and desulphurization. The molten steel composition is then transported to a ladle metallurgy furnace to further adjust chemistry and temperature.

The present invention discloses a method for producing a hypereutectoid steel rail resistant to contact fatigue. The method includes performing molten iron desulphurization, converter smelting, LF refining, RH refining, continuous casting and billet heating, rolling and heat treatment after rolling to obtain a steel rail; the heat treatment after rolling includes performing accelerated cooling and air cooling on the center of a tread of a rail head, both sides of the rail head and the center of a rail bottom of the steel rail obtained after rolling, wherein the starting cooling temperature of the accelerated cooling is 650-900? C., the cooling rate is 1.0-5.0? C./s, and the final cooling temperature is 400-550? C.; and after reaching the final cooling temperature, the accelerated cooling is stopped and it is air-cooled to room temperature. The hypereutectoid steel rail has higher purity, better contact fatigue resistance and good wear resistance.

A method for producing ductile iron alloys and products thereof, and in particular ductile iron alloys with at least a partial pearlitic structure, is disclosed. The improved ductile iron alloy may be used in vehicle parts, in particular disc brake rotors. The method for producing a ductile iron alloy includes heating an initial composition in a furnace to produce a molten mixture, transferring the molten mixture to an inoculation ladle, inoculating the molten mixture with an inoculant for a predetermined inoculation time to produce an inoculated molten mixture, and pouring the inoculated molten mixture into a mold to produce a ductile iron alloy with at least a partial pearlitic structure.

A thin steel sheet contains, in terms of percentage by mass, from 0.010 to 0.200% of C, more than 2.00% and 4.00% or less of Si, from 0.01 to 3.00% of Mn, 3.00% or more and less than 10.00% of Ni, from 11.00 to 20.00% of Cr, from 0.010 to 0.200% of N, from 0 to 3.00% of Mo, from 0 to 1.00% of Cu, from 0 to 0.008% of Ti, from 0 to 0.008% of Al, and the balance of Fe, with unavoidable impurities; and having a number density of a non-metallic inclusion lining up with an interparticle distance in the rolling direction of 20 mm or less and an interparticle distance in the sheet thickness direction of 10 mm or less that has a length in the rolling direction of 40 mm or more of 3.0 or less per square millimeter on the L cross section.