26 results about "Deoxidized steel" patented technology

The invention belongs to the technical field of steelmaking, and relates to a method for controlling large-size inclusions in silicon-aluminum deoxidized steel. Converter tapping adopts a silicon-aluminum deoxidation process, after tapping, high-oxidability slag is removed by adopting a slagging-off process, and then high-reducibility premelting refining slag is added for re-slagging, so that the slag (TFe + MnO) at most of the refining moments is maintained within 0.50%; in the refining process, the stirring strength is controlled to control the desulfurization rate of the refining slag within 50%, so that the slag entrapment degree of the refining slag is reduced to the maximum extent; two iron sheets with the thickness being 2 mm are placed on the liquid level of the slag in advance before RH vacuum treatment, it is guaranteed that the slag is prevented from being drawn into the dip pipe in the process that the dip pipe is inserted into the molten steel, soft blowing is conducted for 10-15 min after RH vacuum treatment, then argon is closed, and the molten steel is subjected to standing for 20-30 min. By the adoption of the smelting process, the product rejection rate caused by large-size inclusions is reduced to be within 2%.

The invention discloses a technological method for regulating and controlling the melting point and viscosity of aluminum deoxidized steel refining slag based on rare earth cerium, and belongs to the technical field of ferrous metallurgy refining. The redox characteristic of Ce and slag system structure modification are combined, the limitation of traditional single component adjustment is broken through, and the composite oxide effect of Ce is utilized: Ce generates CeO2 and Ce-Al-O composite oxide at high temperature, so that the liquidus temperature of a slag system is remarkably reduced, and the melt structure is optimized; by limiting the addition amount of Ce and balancing the cost and performance, the situation that the oxidability of a slag system is out of control due to excessive Ce is avoided, and the thermodynamic stability of the slag system is improved; the addition of Ce inhibits the generation of high-melting-point calcium aluminate and promotes the formation of a low-melting-point phase; by adding Ce, melting point reduction, viscosity optimization and molten steel purification are achieved at the same time, the additive is superior to an existing single-function additive, traditional fluorite is replaced, and fluorine pollution is reduced. The invention aims to provide the same environment-friendly and efficient method capable of accurately regulating and controlling the physicochemical properties of the slag.

The invention discloses a method for replacing a calcium wire feeding process with rare earth treatment for aluminum deoxidized steel, which comprises the following steps of: 1, controlling a narrow window process in a smelting process to meet the cleanliness condition of molten steel before rare earth is added, optimizing and executing the following processes to realize better molten steel cleanliness in the steel, meanwhile, the control range of the content of acid-soluble aluminum [Al] in the steel is 0.020-0.050%; and 2, adding rare earth, namely adding a certain amount of rare earth cerium-iron alloy at the last stage after LF refining deoxidation alloying according to the content of acid-soluble aluminum [Al] in different ranges in the steel. The invention aims to effectively improve the production time sequence of the smelting process, further realize the control effect of high-cleanliness molten steel through the deep purification effect of strong deoxidation and desulfurization of high-reducibility lanthanum-cerium rare earth on the molten steel, simultaneously realize the purpose of reducing the manufacturing cost, and eliminate the problem of smoking caused by a calcium treatment process.

The invention provides high-nitrogen silicon deoxidized steel and a smelting method thereof, and relates to the field of metal casting. According to the smelting method of the high-nitrogen-silicon deoxidized steel, the technology of converter, refining, continuous casting, heating, rolling and air cooling is adopted, the nitrogen content in the target molten steel is accurately controlled through Thermo-Calc software, and the high-nitrogen-silicon deoxidized steel which is good in comprehensive mechanical property and free of longitudinal cracks and other defects is stably obtained on the basis that the simple smelting technology is adopted. The metallographic structure of the high-nitrogen and high-silicon deoxidized steel obtained through the smelting method of the high-nitrogen and high-silicon deoxidized steel is pearlite and ferrite, and the grain size is 9-11 grades. The tensile strength is not less than 730 MPa, the yield strength is not less than 580 MPa, the percentage elongation after fracture is not less than 14%, and the application prospect is wide.

The invention provides a method for smelting nickel-containing steel grade by using a diamond wire, which comprises the following steps: adding the diamond wire, scrap steel and molten iron into a converter for oxygen blowing smelting to obtain converter molten steel; the converter molten steel is transferred into a steel ladle for deoxidation treatment, and deoxidized molten steel is obtained; transferring the deoxidized molten steel into a refining furnace for desulfurization and deoxidation to obtain refined molten steel; the refined molten steel is subjected to nickel adjusting treatment, and nickel-containing molten steel is obtained; and the nickel-containing molten steel is subjected to continuous casting treatment, and the nickel-containing steel billet is obtained. Wherein the absolute value of the difference value between the actual nickel content in the nickel-containing molten steel and the target nickel content in the nickel-containing molten steel is not larger than 0.005%. According to the method provided by the invention, the diamond wire is added into the converter along with the scrap steel and the molten iron, and the diamond wire is molten through oxygen blowing smelting, so that the nickel yield is ensured, the use amount of the nickel-iron alloy is greatly reduced under the condition that the nickel content in the prepared nickel-containing steel grade reaches the preset target value, the cost is reduced, and the production benefit can be effectively improved.

The invention discloses a magnesium-silicon-aluminum submersed nozzle lining material which comprises the following components in percentage by mass: 88%-98% of a base material, 1-10% of an additive; 0.5%-3% of a melting point regulator; the matrix material comprises MgO-SiO2-Al2O3 ternary components which are distributed in a range limited by a connecting line of four specific points A, B, C and D of a MgO-SiO2-Al2O3 ternary phase diagram and two liquidus lines at 1600 DEG C and 1700 DEG C; the method can be applied to continuous casting submersed nozzles, can also be applied to the high-temperature-resistant industry fields such as anti-blocking of steel ladle long nozzles adopting aluminum deoxidized steel and anti-nodulation of tundish stopper rods, and solves the problem that the submersed nozzles are easy to nodulate and block in the pouring process of aluminum deoxidized steel such as automobile sheets at present; the volume density of the magnesium-silicon-aluminum submersed nozzle lining material is 2.65-2.80 g / cm < 3 >, the apparent porosity is 10-15%, and the thermal shock resistance is gt; and 10 times (1100 DEG C-water cooling) are carried out, and the number of continuous casting furnaces in the actual use process is 8-15 times.

The invention provides a method for improving the purity of stainless steel, a 21Cr12MoV stainless steel ingot, a 21Cr12MoV stainless steel forge piece and a preparation method and application of the 21Cr12MoV stainless steel ingot and the 21Cr12MoV stainless steel forge piece, and belongs to the technical field of smelting. The method provided by the invention comprises the following steps: smelting raw materials to obtain molten steel; the molten steel is subjected to VD refining under the argon blowing condition, and refined molten steel is obtained; mixing the refined molten steel with a deoxidizing agent, and deoxidizing under the protection of argon to obtain deoxidized molten steel; the deoxidized molten steel is subjected to protective pouring, and a steel ingot is obtained; and the steel ingot is subjected to electroslag remelting, and the stainless steel ingot is obtained. According to the method, VD refining is adopted, argon blowing is conducted at the same time, then the deoxidizing agent is adopted, protective pouring and electroslag remelting are matched, the inclusion content can be reduced to the maximum extent, the purity of molten steel is improved, and then the mechanical property and heat resistance of the forge piece are improved.

The invention discloses an efficient deep desulfurization method for silicomanganese deoxidized steel. The invention provides a two-step deep desulfurization process for silicomanganese deoxidized steel, aiming at solving the technical problem of weak desulfurization capacity of a steel slag system adopting a silicomanganese deoxidation process. The method comprises the following steps: 1, adding lime and a high-aluminum slag surface deoxidizer into a steel ladle during tapping of a primary smelting furnace for primary slagging and pre-desulfurization; and 2, at an LF refining station, slagging and desulfurization materials such as lime, carbon powder and calcium carbide are synchronously added to the slag surface during power transmission, and the molten steel deep desulfurization of the silicomanganese deoxidized steel is realized by utilizing good dynamic conditions of high temperature of a slag-metal interface, high alkalinity of slag, strong reducibility of the slag and the metal during power transmission and sufficient reaction of the slag and the metal. According to the method, the good desulfurization environment in the tapping period of the primary smelting furnace and the good desulfurization environment in the power transmission period of the LF refining furnace can be fully utilized, the end-point sulfur content of the primary smelting furnace is stably reduced from 0.04% to 0.0050% or below, the deep desulfurization bottleneck of the silicomanganese deoxidized steel is solved, and the method has the advantages of being easy and convenient to operate, high in efficiency and low in cost.

This invention discloses a low-carbon magnesium-carbon refractory material for smelting silicon-manganese deoxidized steel and its preparation method; the method includes the following steps: S1, preparing CMA fine powder; wherein, CMA is a limited solid solution of magnesium oxide in calcium hexaaluminate, containing Ca2Mg2Al 28 O 46 With CaMg2Al 16 O 27 Two core components: CMA fine powder is prepared from 6.93 wt% calcium oxide powder, 89.65 wt% alumina powder, and 3.42 wt% magnesium oxide powder; S2, magnesium oxide fine powder, CMA fine powder, Al powder, and B4C powder are mixed to obtain the first mixture; magnesium oxide aggregate is mixed with phenolic resin, and then natural flake graphite is added and mixed again to obtain the second mixture; S3, the first mixture and the second mixture are mixed to obtain the target mixture; S4, the target mixture is pressed into a crucible blank and cured to obtain a low-carbon magnesium-carbon refractory material for smelting silicon-manganese deoxidized steel. The low-carbon magnesium-carbon refractory material for smelting silicon-manganese deoxidized steel exhibits improved thermal shock resistance, enhanced oxidation resistance, and improved slag resistance, showing good application prospects in the smelting process of silicon-manganese deoxidized steel.

The application discloses a ladle and a method for efficiently removing inclusions in molten steel, wherein four air bricks are evenly and dispersedly arranged at the bottom of the ladle, one taphole is arranged between any two adjacent air bricks, and the air bricks are distributed at the position of 50-60% of the radius of the ladle. The method comprises the following steps: connecting the molten steel with the ladle provided with the four air bricks, adding alloy and carbon powder deoxidation alloying to the ladle in the process of tapping from a converter or an electric furnace, then adding lime and fluorite to build slag, and then transporting the molten steel to LF refining for treatment after the tapping is completed; adjusting the composition and temperature of the molten steel and the composition of the slag in the process of LF refining; after reaching the standard, carrying out calcium treatment through aluminum deoxidization, then carrying out soft stirring, directly carrying out soft stirring treatment on the silicon-manganese deoxidized steel, and directly transporting the molten steel to continuous casting for pouring after the soft stirring is completed. The application solves the problem of excessive inclusions caused by the fact that the molten steel has many dead angles in the process of soft blowing of the ladle and the inclusions are not sufficiently floated.

The present invention discloses a method for cold-state full recovery and reuse of aluminum-calcium refining slag, which belongs to the technical field of solid waste reuse in iron and steel metallurgy. The classic aluminum-calcium refining slag produced by reduction desulfurization processes such as LF refining and converter top slag modification has the characteristics of low phosphorus content, high alkalinity, low melting point and certain sulfur content. The method of the present invention can realize cold-state full recovery, reprocessing and reuse of the aluminum-calcium refining slag in the converter steelmaking system. The recovered aluminum-calcium refining slag block and the recovered aluminum-calcium refining slag powder composite pelletizing by-product can be applied to metallurgical links such as converter oxidation dephosphorization slag making, silicon deoxidation steel top slag modification, LF stirring decarburization and fluxing, realizing true cold-state full recovery and reuse of aluminum-calcium refining slag, which has positive significance in reducing environmental pollution, improving the quality of steel slag hot stewing by-products, and reducing steelmaking costs.

This application relates to a method for improving the castability of ordinary carbon steel Q235B, comprising: mixing scrap steel with molten iron and performing oxygen blowing smelting to obtain a first molten steel; performing a first deoxidation on the first molten steel to obtain a first deoxidized molten steel; performing preliminary alloying on the first deoxidized molten steel to obtain a second molten steel; adjusting the temperature of the second molten steel to a set temperature; performing a second deoxidation on the second molten steel at the set temperature to obtain a second deoxidized molten steel; performing final alloying on the second deoxidized molten steel to obtain a third molten steel; and purifying and stirring the third molten steel to obtain pure molten steel. By synergistically controlling the amount of ferrosilicon added during steelmaking and refining, and utilizing the difference in residual calcium absorption rate, calcium enrichment is achieved while precisely controlling silicon content. This method can stabilize the calcium content in molten steel without adding calcium-based alloys, promote the transformation of inclusions into liquid inclusions, thereby improving the purity of molten steel and continuous casting castability, ultimately ensuring long-term stable casting by the casting machine.

The application provides a method for determining the content of aluminum impurities in alloy raw materials for smelting silicon-manganese deoxidized steel, and belongs to the technical field of iron and steel metallurgy. In the method, high-temperature laser confocal microscopy is used to float and gather inclusions in a steel sample to the surface of the sample; a cathodoluminescence instrument is used to obtain a cathodoluminescence image of the inclusions on the surface of the sample; and whether the content of aluminum impurities in the form of alloy impurities in the silicon-manganese deoxidized steel exceeds a threshold value affecting the performance of the steel is determined according to the gathering morphology of the inclusions and the color characteristics of the cathodoluminescence in the image. The method has good universality, can be applied to the determination of the quality of alloy raw materials for smelting silicon-manganese deoxidized steel, and can improve the accuracy of the determination of the content of aluminum in the alloy.

The application discloses a refining light treatment process based on tapping process metallurgy, which comprises the following steps: hot metal desulfurization pretreatment, converter smelting, converter tapping metallurgy and refining light treatment; the converter tapping metallurgy step comprises the following steps: adding refining slag or furnace slag modifier along with the steel flow during tapping; the material adding sequence of SiMn deoxidized steel in the tapping process is as follows: pre-melted slag material, lime, silicon manganese, aluminum block and alloy; the material adding sequence of Al deoxidized steel in the tapping process is as follows: aluminum block, pre-melted slag material, lime, silicon manganese and alloy; the pre-melted slag material is added when 1 / 5-2 / 5 of the steel is tapped, and the adding amount is 2.0-5.0 kg / t·steel; the lime is added after the pre-melted slag material, and the adding amount is 1.5-5.0 kg / t·steel; after the steel is tapped, the top slag modifier is added on the slag surface, and the adding amount is 0.5-3.0 kg / t·steel. The LF / RH furnace treatment time of the process is controlled to be less than 20 minutes, so that the molten steel refining time is greatly shortened, the material consumption, temperature loss and refractory loss are reduced, and meanwhile, the molten steel quality and cleanliness and the castability of the continuous casting molten steel are ensured.

This invention discloses a method for controlling inclusions in titanium-containing ultra-low carbon steel. The steelmaking process is as follows: converter process – LF process – RH process – slab continuous casting process. After aluminum deoxidation and alloying in the RH process, low-reactive slag is added. As the vacuum molten steel circulates, this slag floats to the surface and remains at the steel-slag interface, hindering oxygen transfer from the ladle slag to the molten steel. Simultaneously, this substance has the ability to adsorb inclusions in the steel. By controlling the process parameters of the RH process, oxygen transfer from the ladle slag to the molten steel is effectively prevented, avoiding secondary oxidation of titanium and aluminum elements in the deoxidized steel and controlling the inclusion content in the steel. This invention's control method effectively prevents oxygen transfer from the ladle slag to the molten steel and avoids secondary oxidation of easily oxidized elements such as titanium and aluminum in the deoxidized steel, resulting in significant economic and social benefits.

The invention relates to a preparation method of ultra-low-oxygen low-impurity high-purity water-atomized pure iron powder. The preparation method comprises the steps of raw material pretreatment, primary smelting (pre-deoxidation), refining (deep deoxidation), molten steel purification, atomization treatment to obtain iron powder slurry, iron powder slurry dehydration, drying and magnetic separation to obtain the ultra-low-oxygen low-impurity pure iron powder. According to the method, through full-process control of raw material optimization, composite refining and multi-stage purification, the oxygen content of the iron powder is smaller than or equal to 0.15%, the total impurity content is smaller than or equal to 0.05%, the ASTM F1580 medical metal powder standard is met, the production cost is reduced, meanwhile, technological obstacles are overcome, and the technological optimization meets the high-added-value application requirements of MIM feeding, high-frequency soft magnetism, ASTM F1580 medical metal powder and the like.

The invention discloses a Q355B series aluminum-containing steel grade deoxidation post-treatment method, which belongs to the technical field of metallurgy, and comprises the following steps: converter tapping pre-deoxidation: in the converter tapping process, sequentially adding silicon manganese alloy, silicon iron, lime and carbon powder for pre-deoxidation; lF refining deep deoxidation: after the molten steel reaches an LF furnace, performing oxygen determination analysis, and adding aluminum blocks, aluminum wires and aluminum particles for deep deoxidation according to an oxygen content calculation result; in the LF refining process, the total adding amount of lime is controlled to be 1400 kg / 200 tons of steel, and the argon blowing stirring time is optimized to be 180 s; inclusions are controlled, specifically, low-melting-point MnO-SiO2 composite oxide is generated through silicon-manganese and silicon-iron pre-deoxidation, the average size of B-type inclusions is reduced to a first target value, and the area proportion is reduced to a second target value. According to the method, joint optimization of deoxidation, desulfurization and inclusion control is achieved in a post-deoxidation mode of'silicon-manganese and silicon-iron pre-deoxidation + LF aluminum deep deoxidation '.

This invention discloses a deoxidized steel block and a method for deoxidizing molten steel, relating to the field of molten steel deoxidation technology. The deoxidized steel block and method employ a circumferentially arranged spray structure, which rotates the steel block when magnesium gas is sprayed, thereby ensuring uniform diffusion of the magnesium gas in the molten steel. By setting the spray structure at the top of the steel block, this method essentially eliminates the requirement for a specific steel block density (magnesium content), and the magnesium gas sprayed from the top spray structure propels the steel block towards the bottom of the molten steel.

The application discloses a method for improving cleanliness of pre-deoxidized steel. The technological process of molten steel smelting is as follows: converter process-LF process-RH process-slab continuous casting process, after the end of vacuum decarburization in the RH process, a steel-slag interface barrier agent is added, and the treatment process parameters of the RH process are controlled, so that oxygen transmission from the ladle slag to the molten steel is effectively prevented, secondary oxidation of titanium and aluminum elements in the deoxidized steel is avoided, and the content of inclusions in the steel is controlled. The application effectively solves the problem of secondary oxidation of the molten steel by the ladle slag after the end of the RH decarburization of the existing pre-deoxidized steel to the continuous casting pouring process, and has remarkable economic and social benefits.

The invention discloses a method for producing high-purity iron through an industrial pyrogenic process. The method comprises the working procedures of an HIsmelt smelting furnace reduction furnace, molten iron pretreatment, electric furnace duplex, LF refining, RH vacuum treatment and continuous casting. According to the method, an HIsmelt smelting furnace is adopted to reduce molten iron, and low-silicon, low-manganese, low-phosphorus and low-sulfur initial molten iron is obtained through a molten iron pretreatment ultra-deep desulfurization and slagging-off process; electric furnace duplex smelting is adopted for further deep removal of manganese and phosphorus, slag can be discharged below zero by adopting electric furnace steel remaining operation and eccentric furnace bottom tapping, and the problem of phosphorus, silicon and manganese return during subsequent LF furnace ultra-deep desulfurization is solved; the LF furnace adopts high-alkalinity reducing slag for further ultra-deep desulfurization; oB forced vacuum decarburization is adopted in an RH furnace, residual oxygen is removed through a calcium-magnesium-aluminum composite deoxidizer after decarburization is finished, the composite deoxidizer has the advantages that oxygen in the molten steel can be removed to an extremely low level under the condition that the concentration of Al% and the concentration of Ca% are very low, the problem of castability of subsequent continuous casting of the aluminum deoxidized steel is solved through Ca in the molten steel, and 3N5-4N-grade high-purity iron can be obtained.

The invention belongs to the technical field of ferrous metallurgy, and particularly relates to a cathode luminescence image-based rapid identification method for aluminum deoxidized steel inclusion components. The rapid identification method comprises the following steps: acquiring cathode luminescence images of the inclusions, judging the components of the inclusions according to the color difference of the cathode luminescence images, measuring the fractal dimensions of the inclusions with the same cathode luminescence color according to the contour of the inclusions in the cathode luminescence images, and determining the fractal dimensions of the inclusions according to the fractal dimensions. And color and fractal dimension information are combined to jointly judge the inclusion components. The rapid identification method is applied to aluminum deoxidized steel inclusion control, the steelmaking production condition can be rapidly judged, the harm of the inclusion is reduced, and the steel product quality is stabilized.

This application relates to a method for improving the absorption rate of rare earth elements in ultra-low carbon steel, belonging to the field of steelmaking technology. The method includes: obtaining RH-refined molten steel entering the RH refining station; decarburizing the RH-refined molten steel while maintaining a vacuum degree of less than 100 Pa during the RH refining process until the carbon content of the molten steel reaches a set carbon content, obtaining decarburized molten steel; deoxidizing the decarburized molten steel, obtaining deoxidized molten steel; chemically reacting rare earth blocks with inclusions in the deoxidized molten steel to effectively modify the inclusions, obtaining RH-refined molten steel exiting the RH refining station; and quenching the RH-refined molten steel to ensure sufficient reaction between the rare earth elements and inclusions in the molten steel. By precisely controlling various parameters during the RH refining process, efficient absorption of rare earth elements in the molten steel is achieved.

The invention provides a method for improving the purity of stainless steel, a 316LN stainless steel ingot, a 316LN stainless steel forge piece and a preparation method and application of the 316LN stainless steel ingot and the 316LN stainless steel forge piece, and belongs to the technical field of smelting. The method for improving the purity of the stainless steel comprises the steps that raw materials are smelted, and molten steel is obtained; the molten steel is subjected to VODC refining, and refined molten steel is obtained; the VODC refining comprises a VOD stage, a VCD stage, a VOH stage and a VD stage which are sequentially carried out; a first deoxidizing agent is added in the VOH stage; mixing the refined molten steel with a second deoxidizing agent, and deoxidizing under the protection of argon to obtain deoxidized molten steel; the deoxidized molten steel is subjected to protective pouring, and a steel ingot is obtained; and the steel ingot is subjected to electroslag remelting, and the stainless steel ingot is obtained. VODC refining is adopted, the deoxidizing agent is added in the VOH stage, then the deoxidizing agent is added again, and the purity of the molten steel can be improved in cooperation with protective pouring and electroslag remelting.

The invention discloses a low-cost deoxidation process for converter steelmaking. The low-cost deoxidation process comprises the steps of converter deoxidation, ladle deoxidation, vacuum deoxidation and the like. According to the method, a segmented deoxidation process is adopted, the carbon powder is added firstly, then the composite deoxidizer is added, and the silicon-calcium-barium-aluminum composite deoxidizer is adopted, so that compared with an existing aluminum deoxidation process, the use amount of aluminum is reduced by 50-60%, the deoxidation cost is reduced, inclusions generated by aluminum deoxidation can be deformed through calcium and barium, the yield of aluminum is 75% or above, and the method is suitable for industrial production. Oxide inclusions in the steel are obviously reduced, and after vacuum deoxidation treatment, the total oxygen content in the steel is effectively reduced, and the quality of molten steel is improved. The method has the advantages of controllable inclusion in steel, good deoxidation effect, stable product quality and low deoxidation cost.

The present invention discloses a powder injection refining process for the production of rare earth oxide dispersion strengthened alloys, belonging to the technical field of alloy smelting. During tapping from the converter, 4.5 - 8.5 kg / t of ferrosilicon aluminum is used for strong deoxidation; after tapping is completed, 0.2 - 0.4 kg / t of rare earth aluminum alloy is added to the slag surface of the ladle for slag surface deoxidation; the molten steel is transported to the powder injection station, the temperature of the molten steel is adjusted to 1570 - 1610 °C, and the rare earth blowing powder agent is sprayed into the molten steel at a high speed using an inert carrier gas. The working pressure of the carrier gas for powder injection in the ladle is 3.0 - 4.0 bar, the carrier gas flow rate is 40 - 60 m<supgt;3< / supgt> / h, the powder injection speed in the ladle is 10 - 50 kg / min, and the dosage of the blowing powder agent is 1.0 - 50.0 kg / t. After adopting this powder injection refining process, the content of dissolved oxygen in the steel can be increased to more than 100 ppm, and the dissolved content of RE elements can be increased to more than 300 ppm to form an alloy strengthened by nano-rare earth oxide dispersion.

The application discloses a low-silicon steel smelting method, which comprises the following steps: (1) molten iron after pretreatment is loaded into a converter, double-slag operation is adopted in a smelting process, a part of desilicon slag is poured out after desilicon is finished, new slag is made to decarburize, and the basicity of converter slag is controlled; (2) converter tapping is carried out, carbon powder is added into a ladle to pre-deoxidize, and manganese alloy and aluminum pills are added into the ladle to deeply deoxidize when tapping reaches a certain degree; and (3) the molten iron is loaded into an LF furnace, carbon powder is used for diffusion deoxidization of a slag surface, and high-basicity refining slag is made in a refining process. The smelting method can effectively avoid that the silicon content of the molten iron exceeds a standard in the smelting process, and continuously cast the molten iron.