The method employs a desulfurization agent that is introduced into a smelt of one of molten pig iron and molten steel. The desulfurization agent contains calcium oxide, bitumen and at least one flux agent, with the agent containing 1 to 10% by weight bitumen.

A method of casting a steel semi-product from a liquid steel, the steel semi-product having a targeted composition in titanium of at least 3.5% in weight.

Disclosed is a slag discharging method in a process of producing ultra-low phosphorus steel, which relates to the technical field of iron and steel smelting, and in which molten steel is mixed with lime first to produce basic slag; then converting is performed with oxygen to increase the oxidizability of the basic slag; and a carbon-containing reducing agent is finally added, so that in the process that the carbon is oxidized to release a large amount of carbon monoxide gas, phosphates are captured, and the basic slag is rapidly foamed and overflows from the opening of the steel ladle, so that conditions are no longer available for rephosphorization. Also disclosed is a method for producing ultra-low phosphorus steel, which includes the above-described slag discharging method in a process of producing ultra-low phosphorus steel, and refining and ingotting after slag discharge.

The present disclosure provides a method of making non-grain oriented (NGO) electrical steel. The method includes tapping the liquid steel out of a primary steelmaking furnace. Deoxidizing the liquid steel before or after transferring the deoxidized liquid steel to a ladle metallurgy furnace. Removing sulfur at the ladle metallurgy furnace (LMF). Adding fluxes and deoxidizer to the ladle slag and/or skimming off ladle slag to prevent sulfur reversion. Transferring the liquid steel from the ladle metallurgy furnace to an RH degasser for carbon removal by blowing oxygen. Adding fluxes at the RH before oxygen blowing to fortify the bottom layer of the ladle slag to prevent sulfur reversion. The removal of oxygen and sulfur prior to transferring the liquid steel to the RH degasser facilitates nitrogen removal and prevents carbon pick up during the step of adding fluxes and arcing for sulfur removal if sulfur removal is carried out at the LMF after carbon removal at the RH degasser in the conventional process. Oxygen blowing at the RH also lowered the titanium pickup from the earlier desulfurization process. The ultra low levels of carbon, nitrogen, sulfur, and titanium in the NGO steel made using this method enabled the excellent magnetic properties achieved in the finishing NGO products.

Raw material feed into an electric arc furnace (“EAF”) is melted into heated liquid metal at a controlled temperature with impurities and inclusions removed as a separate liquid slag layer. The heated liquid metal is removed from the EAF into a passively heatable ladle wherein it is moved into a refining station where they are placed into a inductively heated refining holding vessel and wherein vacuum oxygen decarburization is applied to remove carbon, hydrogen, oxygen, nitrogen and other undesirable impurities from the liquid metal. The ladle and liquid metal is then transferred to a refining station/gas atomizer having a controlled vacuum and inert atmosphere wherein the liquid metal is poured from an inductively heated atomizing holder vessel into a heated tundish at a controlled rate wherein high pressure inert gas is applied through a nozzle to create a spray of metal droplets forming spherical shapes as the droplets cool.

A fluorite synthetic stone comprises: (a) a glass matrix comprising Ca, Si and O, and having a predetermined weight ratio of Ca to Si; and (b) CaF.sub.2 crystals dispersed in the glass matrix at a concentration of at least about 70 wt.%. A method of making fluorite synthetic stones includes formulating a particulate mixture comprising: CaF.sub.2 crystals at a concentration of at least about 70 wt.%; and an excipient having a predetermined weight ratio of Ca to Si. Aggregates are prepared from the particulate mixture. The aggregates are heat treated to form a plurality of fluorite synthetic stones, where each synthetic stone comprises: a glass matrix comprising Ca, Si and O; and CaF.sub.2 crystals dispersed in the glass matrix at a concentration of at least about 70 wt.%.

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.

A CrMnN austenitic heat-resistant steel is provided. The heat-resistant steel comprises, in weight percentage, carbon 0.20% to 0.50%, silicon 0.50% to 2.00%, manganese 2.00% to 5.00%, phosphorus less than 0.04%, sulphur less than 0.03%, chromium 20.00% to 27.00%, nickel 6.00% to 8.00%, molybdenum less than 0.50%, niobium less than 0.60%, tungsten less than 0.60%, vanadium less than 0.15%, nitrogen 0.30% to 0.60%, zirconium less than 0.10%, cobalt less than 0.10%, yttrium less than 0.10%, boron less than 0.20%, with the balance iron. The heat-resistant steel has high temperature strength, high thermal conductivity, low thermal expansion coefficient, good dimensional stability, good ductility, heat resistance, impact resistance, and low production costs, and meets the requirements for high performance engines.

Proposed is a method for removing phosphorus from a phosphorus-containing substance which is applicable in an industrial scale so as to effectively reduce phosphorus contained in the phosphorus-containing substance. In this method, the phosphorus-containing substance used as a raw material for metal smelting or metal refining is reacted with a nitrogen-containing gas at a treatment temperature T ( C.) which is lower than a melting temperature (T.sub.m) of the substance, so that phosphorus is removed preferably in the form of phosphorus nitride (PN). In this regard, a nitrogen partial pressure and an oxygen partial pressure in the nitrogen-containing gas are preferably controlled, thereby reducing a load of dephosphorization process, for example.

Disclosed is a slag discharging method in a process of producing ultra-low phosphorus steel, which relates to the technical field of iron and steel smelting, and in which molten steel is mixed with lime first to produce basic slag; then converting is performed with oxygen to increase the oxidizability of the basic slag; and a carbon-containing reducing agent is finally added, so that in the process that the carbon is oxidized to release a large amount of carbon monoxide gas, phosphates are captured, and the basic slag is rapidly foamed and overflows from the opening of the steel ladle, so that conditions are no longer available for rephosphorization. The slag discharging method is simple and convenient to operate, does not have high requirements on the equipment, has relatively good dephosphorization effect, and can be used to prepare an ultra-low phosphorus steel containing less than 0.003% phosphorus. Also disclosed is a method for producing ultra-low phosphorus steel, which comprises the above-described slag discharging method in a process of producing ultra-low phosphorus steel, and refining and ingotting after slag discharge. The production method has good dephosphorization effect, has a low production cost, and can high-efficiently produce an ultra-low phosphorus steel containing less than 0.003% phosphorus.