CN-116372128-B - Continuous casting method of high-aluminum carbon steel and preparation method thereof

Abstract

The application relates to the technical field of steelmaking continuous casting, in particular to a high-aluminum carbon steel slab continuous casting method and a preparation method thereof. The continuous casting method comprises the steps of transferring molten steel from a tundish to a crystallizer, controlling the depth of a submerged nozzle inserted into the molten steel and the argon blowing flow of a stopper rod and an upper nozzle, adding casting powder into the molten steel in the crystallizer, performing continuous casting, and controlling the chemical components and consumption of the casting powder to obtain a casting blank. The application realizes the stability of heat transfer and lubrication of the crystallizer after the covering slag is denatured, and the high-aluminum carbon steel casting blank has no surface defects such as longitudinal crack, transverse crack, dent and the like, and realizes higher pull rate production.

Inventors

• ZHU KERAN
• WU YOUYI
• LI BIN
• CHAI GUANGWEI
• GONG JIAN
• HUANG FUXIANG
• PEI XINGWEI
• LIU CHUNYANG

Assignees

• 首钢股份公司迁安钢铁公司
• 北京首钢股份有限公司

Dates

Publication Date

20260508

Application Date

20230328

Claims (5)

1. 1. A method of continuous casting of high aluminum carbon steel, the method comprising: Transferring molten steel from a tundish to a crystallizer, and controlling the depth of a submerged nozzle inserted into the molten steel and the argon blowing flow of a stopper rod and an upper nozzle; adding casting powder into the molten steel in the crystallizer, performing continuous casting, and controlling chemical components and consumption of the casting powder to obtain a casting blank; The chemical components of the covering slag comprise CaO, siO 2 、Al 2 O 3 、MgO、Na 2 O, F and Li 2 O, wherein, The content of Al 2 O 3 is <1.0 wt%, the content of MgO is <1.0 wt%, the content of Na 2 O is <2.0 wt%, And the weight of CaO, the weight of SiO 2 , and the weight of Al 2 O 3 satisfy the following relation: [CaO]/([CaO]+[SiO 2 ]+[Al 2 O 3 ])%=55%-60% Wherein [ CaO ] represents the weight of CaO, [ SiO 2 ] represents the weight of SiO 2 , and [ Al 2 O 3 ] represents the weight of Al 2 O 3 ; the depth of the immersion nozzle inserted into the molten steel is 150mm-180mm; the argon blowing flow rates of the stopper rod and the upper nozzle are both 0; The consumption of the mold flux was 0.4kg/m 2 -0.6kg/m 2 .
2. 2. The method according to claim 1, wherein, among chemical components of the mold flux, The content of CaO is 35.0-50.0 wt%, the content of SiO 2 is 25.0-40.0 wt%, the content of F is 5.0-15.0 wt%, and the content of Li 2 O is 0.5-4.5 wt%.
3. 3. The method according to claim 1 or 2, wherein the basicity of the mold flux is 1.2-1.5.
4. 4. The method according to claim 1, wherein the casting block is obtained by adding mold flux to the molten steel in the mold, performing continuous casting, and controlling chemical components and consumption of the mold flux, comprising: adding casting powder into the molten steel in the crystallizer, performing continuous casting, controlling chemical components, consumption and physical parameters of the casting powder to obtain a casting blank, wherein, The physical parameters of the mold flux include the melting point of the mold flux and the viscosity of the mold flux.
5. 5. The method according to claim 4, wherein the melting point of the mold flux before use is 900 ℃ to 1100 ℃, the viscosity of the mold flux before use is 0.04 Pa-s to 0.08 Pa-s, and or; the melting point of the used protective slag is less than or equal to 1200 ℃, and the viscosity of the used protective slag is less than or equal to 0.15 Pa.s.

Description

Continuous casting method of high-aluminum carbon steel and preparation method thereof Technical Field The application relates to the technical field of steelmaking continuous casting, in particular to a high-aluminum carbon steel slab continuous casting method and a preparation method thereof. Background The high aluminum carbon steel has the carbon content of 0.09-0.25 wt%, the aluminum content of 0.5-2.0 wt% and the silicon content of less than 0.5 wt%, and the high Al content in the molten steel reacts with SiO 2 in the protecting slag to reduce SiO 2 in the protecting slag, so that Al 2O3 is greatly increased and the protecting slag is denatured. At present, after the covering slag is denatured, the high-aluminum carbon steel casting blank has surface defects such as longitudinal crack, transverse crack, dent and the like, and the covering slag is required to be cleaned manually or mechanically, and is forced to be judged to be wasted when serious. Disclosure of Invention The application provides a high-aluminum carbon steel slab continuous casting method and a preparation method thereof, which are used for solving the technical problems that the existing high-aluminum carbon steel slab is easy to have surface defects such as longitudinal cracks, transverse cracks, pits and the like. In a first aspect, the present application provides a method of continuous casting of high aluminium carbon steel, the method comprising: Transferring molten steel from a tundish to a crystallizer, and controlling the depth of a submerged nozzle inserted into the molten steel and the argon blowing flow of a stopper rod and an upper nozzle; And adding casting powder into the molten steel in the crystallizer, performing continuous casting, and controlling the chemical components and consumption of the casting powder to obtain a casting blank. Optionally, the chemical components of the covering slag comprise CaO, siO 2、Al2O3、MgO、Na2 O, F and Li 2 O, wherein the content of Al 2O3 is less than 1.0 wt%, the content of MgO is less than 1.0 wt%, the content of Na 2 O is less than 2.0 wt%, And the weight of CaO, the weight of SiO 2, and the weight of Al 2O3 satisfy the following relation: [CaO]/([CaO]+[SiO2]+[Al2O3])%=55%-60% Wherein [ CaO ] represents the weight of CaO, [ SiO 2 ] represents the weight of SiO 2, and [ Al 2O3 ] represents the weight of Al 2O3. Optionally, in the chemical components of the covering slag, the content of CaO is 35.0-50.0 wt%, the content of SiO 2 is 25.0-40.0 wt%, the content of F is 5.0-15.0 wt%, and the content of Li 2 O is 0.5-4.5 wt%. Optionally, the alkalinity of the covering slag is 1.2-1.5. Optionally, the depth of the immersion nozzle inserted into the molten steel is 150mm-180mm. Optionally, the consumption of the mold flux is 0.4kg/m 2-0.6kg/m2. Optionally, the argon blowing flow rates of the stopper rod and the upper nozzle are both 0. Optionally, adding mold flux to the molten steel in the crystallizer, performing continuous casting, and controlling chemical components and consumption of the mold flux to obtain a casting blank, including: adding casting powder into the molten steel in the crystallizer, performing continuous casting, controlling chemical components, consumption and physical parameters of the casting powder to obtain a casting blank, wherein, The physical parameters of the mold flux include the melting point of the mold flux and the viscosity of the mold flux. Optionally, the melting point of the protective slag is 900-1100 ℃ before use, and the viscosity of the protective slag is 0.04-0.08 Pa-s before use, and/or; the melting point of the used protective slag is less than or equal to 1200 ℃, and the viscosity of the used protective slag is less than or equal to 0.15 Pa.s. In a second aspect, the present application provides a method of producing high aluminium carbon steel, the method comprising the method of any one of the embodiments of the first aspect. Compared with the prior art, the technical scheme provided by the embodiment of the application has the following advantages: The continuous casting method of the high-aluminum carbon steel provided by the embodiment of the application prevents the generation of coarse crystals with high melting points such as gehlenite, magnesia-alumina spinel and nepheline in a mold powder film by controlling the chemical components of the mold powder, evenly transfers heat in the mold by controlling the consumption of the mold powder, stabilizes the performance of the mold powder by controlling the insertion depth of a submerged nozzle, does not perform argon blowing operation at a stopper rod and a water feeding nozzle, and ensures stable lubrication and heat transfer in the mold. In conclusion, the heat transfer and lubrication stability of the crystallizer after the mold flux is denatured can be realized, the surface defects of no longitudinal crack, transverse crack, dent and the like of a high-aluminum carbon steel casting blank ar