WO2021036974A1 - Method for controlling cold-rolled steel defect of titanium-containing ultra-low carbon steel - Google Patents

Method for controlling cold-rolled steel defect of titanium-containing ultra-low carbon steel Download PDF

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WO2021036974A1
WO2021036974A1 PCT/CN2020/110757 CN2020110757W WO2021036974A1 WO 2021036974 A1 WO2021036974 A1 WO 2021036974A1 CN 2020110757 W CN2020110757 W CN 2020110757W WO 2021036974 A1 WO2021036974 A1 WO 2021036974A1
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steel
ultra
titanium
low carbon
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胡汉涛
马志刚
王俊凯
胡会军
林顺财
薛菲
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宝山钢铁股份有限公司
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    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/02Ferrous alloys, e.g. steel alloys containing silicon
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21CPROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21CPROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/0006Adding metallic additives
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21CPROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/04Removing impurities by adding a treating agent
    • C21C7/06Deoxidising, e.g. killing
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/001Ferrous alloys, e.g. steel alloys containing N
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/004Very low carbon steels, i.e. having a carbon content of less than 0,01%
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/005Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/04Ferrous alloys, e.g. steel alloys containing manganese
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/06Ferrous alloys, e.g. steel alloys containing aluminium
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/14Ferrous alloys, e.g. steel alloys containing titanium or zirconium

Abstract

A method for controlling a cold-rolled steel defect of a titanium-containing ultra-low carbon steel. The titanium-containing ultra-low carbon steel has the following components in percentage by weight: C ≤ 0.005%, Si ≤ 0.05%, Mn 0.05-0.3%, Al 0.02-0.1%, Ti 0.008-0.05%, P ≤ 0.05%, S ≤ 0.02%, N ≤ 0.003%, T.O 0.0010-40%, and the balance of Fe and inevitable impurities, in which Al content is greater than or equal to Ti content. After RH vacuum decarburization is finished, Ti is added first, and the addition amount of Ti is controlled at the lower limit value of the finished product value; Al is then added, the addition amount is controlled at the median of the finished product value, and the circulation time of liquid steel is greater than or equal to 3 min; other alloying elements are added and/or the steel melt components are adjusted according to the specification of the finished product, and the circulation time of the steel melt is greater than or equal to 2 min; rare earth metals Ce and La are added, in which the addition amount is REM/T.O = 0.6 - 3.0 by mass ratio, the mass unit of rare earth REM is kg, and the unit of the total oxygen T.O in the steel) is ppm; and the circulation time of the steel melt is greater than or equal to 2 min, and oxide Ce2O3Al2O3 or La2O3Al2O3 is produced in the steel melt.

Description

一种含钛超低碳钢冷轧钢质缺陷的控制方法Method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel 技术领域Technical field
本发明涉及炼钢工艺技术,特别涉及一种含钛超低碳钢冷轧钢质缺陷的控制方法。The invention relates to steelmaking technology, in particular to a method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel.
背景技术Background technique
随着技术的进步,用户对钢质量的要求越来越高。对超低碳钢而言,已经出现对薄至0.05mm厚度冷轧成品板的需求。冷轧成品厚度越薄,冷轧轧制过程中越容易出现脱氧夹杂物(Al 2O 3)所引起的钢质缺陷,用户冲压使用过程中也极易发生脱氧夹杂物所导致的开裂问题。 With the advancement of technology, users have higher and higher requirements for steel quality. For ultra-low carbon steel, there has been a demand for cold-rolled finished plates as thin as 0.05mm. The thinner the thickness of the cold-rolled product, the more likely it is that steel defects caused by deoxidized inclusions (Al 2 O 3 ) will appear during the cold-rolling process, and cracking caused by deoxidized inclusions is also prone to occur during the user's stamping process.
超低碳钢冶炼时,转炉冶炼加入的氧(自由氧和化合态氧)是整个冶炼过程最主要的氧源,随后出钢过程中,含大量氧的钢液和钢渣进入钢包。钢液中的氧除用于真空循环精炼脱碳外,在随后Al脱氧过程中形成Al 2O 3夹杂,这些Al 2O 3常常粘附和富集在水口内壁,影响浇注过程的稳定;保留在钢中的Al 2O 3夹杂,在冷轧过程中极易造成损害钢基体,形成缺陷。特别地,对含Ti超低碳钢,钢液中Ti会加重浇注过程浸入式水口堵塞情况的发生。 When ultra-low carbon steel is smelted, oxygen (free oxygen and chemical oxygen) added by converter smelting is the most important source of oxygen in the entire smelting process. Then, during the tapping process, molten steel and steel slag containing a large amount of oxygen enter the ladle. In addition to the oxygen in the molten steel used for vacuum cycle refining and decarburization, Al 2 O 3 inclusions are formed in the subsequent Al deoxidation process. These Al 2 O 3 often adhere and concentrate on the inner wall of the nozzle, which affects the stability of the casting process; Al 2 O 3 inclusions in the steel can easily cause damage to the steel matrix and form defects during the cold rolling process. Especially, for Ti-containing ultra-low carbon steel, Ti in the molten steel will aggravate the clogging of the immersion nozzle during the casting process.
对于上述问题,存在两种解决思路。从冶炼的角度来看,须将钢中的夹杂物总量降至极低水平且控制钢中无大颗粒夹杂物存在。从夹杂物特性控制的角度,须将残留在钢中夹杂物的危害尽可能降低。现阶段,广泛采用LD-RH-CC工艺流程生产超低碳钢,钢中成品氧可以控制至低于20ppm甚至更低,对应钢中夹杂物总量已达到极低水平,但冷轧成品薄钢板中仍然大量存在由钢中残留Al 2O 3夹杂所导致的钢质封锁。即第1种思路并不能彻底解决冷轧钢质缺陷问题。 There are two solutions to the above problems. From the point of view of smelting, the total amount of inclusions in the steel must be reduced to a very low level and no large-particle inclusions in the steel must be controlled. From the perspective of inclusion characteristics control, the hazards of inclusions remaining in the steel must be reduced as much as possible. At this stage, the LD-RH-CC process is widely used to produce ultra-low carbon steel. The oxygen in the finished steel can be controlled to less than 20ppm or even lower. The total amount of inclusions in the corresponding steel has reached a very low level, but the cold-rolled finished product is thin. There is still a large amount of steel blockade caused by residual Al 2 O 3 inclusions in the steel plate. That is, the first idea cannot completely solve the problem of cold-rolled steel defects.
特别地,含钛超低碳钢生产时,除存在前述由大颗粒Al 2O 3所致的冷轧钢质缺陷外,连铸过程中极易发生浸入式水口堵塞,结晶器液面波动幅度大,且结晶器液面波动幅度随着钢中钛含量的升高,呈加剧趋势,降低了板坯的合格率,增加了后续冷轧钢质缺陷发生率。 In particular, during the production of titanium-containing ultra-low carbon steel, in addition to the aforementioned cold-rolled steel defects caused by large particles of Al 2 O 3 , the immersion nozzle is very likely to be blocked during the continuous casting process, and the mold level fluctuates. The fluctuation range of the crystallizer liquid level increases with the increase of the titanium content in the steel, which reduces the qualification rate of the slab and increases the incidence of subsequent cold-rolled steel defects.
为此,对含钛超低碳钢,需控制钢中氧化物夹杂的特性,且保证冶炼时浇注过程的稳定性,从而降低Al脱氧产物(Al 2O 3)对冷轧钢质的危害。 For this reason, for titanium-containing ultra-low carbon steels, it is necessary to control the characteristics of oxide inclusions in the steel and ensure the stability of the casting process during smelting, so as to reduce the harm of Al deoxidation products (Al 2 O 3 ) to cold-rolled steel.
中国专利公开号CN1678761B涉及向Al脱氧钢中加入稀土金属(REM),加入量为质量比REM/T.O=0.05-0.5(最终氧化物中稀土类氧化物占比0.5-15%),从而减少钢中相邻Al 2O 3颗粒之间FeO或FeO·Al 2O 3的数量,抑制Al 2O 3颗粒的团聚,最终能够提高成品质量。该专利的理论基础是:钢中相邻Al 2O 3颗粒之间存在FeO或FeO·Al 2O。但本发明人发现,两者在钢液中呈液态,致使钢中Al 2O 3夹杂团聚成大尺寸颗粒,这些大尺寸夹杂物颗粒是后续成品质量恶化的重要原因。 Chinese Patent Publication No. CN1678761B relates to the addition of rare earth metals (REM) to Al deoxidized steel with a mass ratio of REM/TO = 0.05-0.5 (the proportion of rare earth oxides in the final oxide is 0.5-15%), thereby reducing steel The amount of FeO or FeO·Al 2 O 3 between adjacent Al 2 O 3 particles can inhibit the agglomeration of Al 2 O 3 particles and ultimately improve the quality of the finished product. The theoretical basis of the patent is: FeO or FeO·Al 2 O exists between adjacent Al 2 O 3 particles in steel. However, the inventor found that the two are liquid in the molten steel, causing the Al 2 O 3 inclusions in the steel to agglomerate into large-sized particles. These large-sized inclusion particles are an important reason for the deterioration of the subsequent finished product quality.
中国专利公开号CN1218839A涉及在钢液脱碳完成后依次使用Ti脱氧,合金化,加入CaSi合金或CaSi-REM合金,控制最终氧化物夹杂组成为Ti 2O 3-CaO或REM氧化物-Al 2O 3的复合夹杂,含少量SiO 2或MnO,其中CaO+REM氧化物质量百分比位于区间[5,50],从而获得改善表面锈蚀率的钢板。该申请的理论依据是:钢中残留的氧化物系夹杂物在特定组成范围内不会造成水口堵塞,而且可以是夹杂物微细分散化(发明人提出),从而制造表面性能良好的钢板。此申请强调其发明的工艺效果是由于控制加入脱氧用的Ti含量(Ti/Al比值),加入的Ca或REM量,使其满足最终夹杂物的组成为含Ti、Ca/REM和Al的氧化物。 Chinese Patent Publication No. CN1218839A relates to the use of Ti for deoxidation, alloying, adding CaSi alloy or CaSi-REM alloy, and controlling the final oxide inclusion composition to Ti 2 O 3 -CaO or REM oxide-Al 2 after the decarburization of molten steel is completed. The composite inclusion of O 3 contains a small amount of SiO 2 or MnO, in which the mass percentage of CaO+REM oxide is in the interval [5, 50], so as to obtain a steel plate with improved surface corrosion rate. The theoretical basis of this application is that the oxide-based inclusions remaining in the steel will not cause nozzle clogging within a specific composition range, and the inclusions can be finely dispersed (proposed by the inventor) to produce a steel sheet with good surface properties. This application emphasizes that the process effect of its invention is due to the control of the Ti content (Ti/Al ratio) added for deoxidation, the amount of Ca or REM added, so that the final inclusion composition is an oxidation containing Ti, Ca/REM and Al Things.
发明内容Summary of the invention
本发明的目的在于提供一种含钛超低碳钢冷轧钢质缺陷的控制方法,以期降低残留在钢中夹杂物的危害的同时,保证冶炼时浇注过程的平稳性,改善冷轧成品表面质量,提高冷轧成品钢质封锁率,以用于冶炼表面和内部质量良好的冷轧钢板。The purpose of the present invention is to provide a method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel, in order to reduce the hazards of inclusions remaining in the steel, while ensuring the stability of the casting process during smelting, and improving the surface of the cold-rolled product Quality, improve the blockage rate of cold-rolled finished steel, so that it can be used to smelt cold-rolled steel plates with good surface and internal quality.
为达到上述目的,本发明的技术方案是:To achieve the above objective, the technical solution of the present invention is:
一种含钛超低碳钢冷轧钢质缺陷的控制方法,该含钛超低碳钢的成分重量百分比为:C≤0.005%,Si≤0.05%,Mn 0.05-0.3%,Al 0.02-0.1%(如0.05-0.1%),Ti 0.008-0.05%,P≤0.05%,S≤0.02%,N≤0.003%,T.O 0.0010~40%,其余为Fe和不可避免杂质,且,Al含量≥Ti含量;所述方法包括:RH真空脱碳结束后,先加入Ti,Ti的加入量为成品规格的Ti含量范围的下限值,再添加Al,Al的加入量为成品规格的Al含量范围的中间值,然后钢液循环,时间≥3min;按照成品规格添加其他合金元素和/或调整钢液成分,钢液循环,时间≥2min;向钢液中加入稀土金属 Ce和/或La,加入量控制为REM/T.O=0.6-3.0,其中,稀土金属REM的加入量以质量计,单位为kg,钢中总氧T.O单位为ppm;钢液循环,时间≥2min,最终钢液中生成氧化物Ce 2O 3·Al 2O 3和/或La 2O 3·Al 2O 3,达到浇注顺行。 A method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel. The composition weight percentage of the titanium-containing ultra-low carbon steel is: C≤0.005%, Si≤0.05%, Mn 0.05-0.3%, Al 0.02-0.1 % (Such as 0.05-0.1%), Ti 0.008-0.05%, P≤0.05%, S≤0.02%, N≤0.003%, TO 0.0010-40%, the rest is Fe and unavoidable impurities, and Al content ≥Ti Content; the method includes: after the RH vacuum decarburization is completed, Ti is added first, the addition amount of Ti is the lower limit of the Ti content range of the finished product specifications, and then Al, the addition amount of Al is the Al content range of the finished product specifications Intermediate value, then molten steel circulation, time ≥3min; add other alloying elements and/or adjust the composition of molten steel according to the finished product specifications, molten steel circulation, time ≥2min; add rare earth metal Ce and/or La to molten steel, add amount Controlled as REM/TO=0.6-3.0, where the amount of rare earth metal REM added is by mass, in kg, and the total oxygen TO in the steel is in ppm; molten steel is circulated for a time ≥2min, and oxides are formed in the final molten steel Ce 2 O 3 ·Al 2 O 3 and/or La 2 O 3 ·Al 2 O 3 , to achieve pouring direct.
在一些实施方案中,所述稀土金属的成分为Ce和任选的La。In some embodiments, the composition of the rare earth metal is Ce and optionally La.
优选的,所述稀土金属的质量百分比为:Ce 60-70%,La 30-40%。Preferably, the mass percentage of the rare earth metal is: Ce 60-70%, La 30-40%.
在一些实施方案中,加入Al后,钢液循环时间≥5min。In some embodiments, after Al is added, the molten steel circulation time is ≥ 5 min.
在一些实施方案中,加入REM后,钢液循环时间≥3min。In some embodiments, after adding REM, the molten steel circulation time is ≥ 3 min.
在一些实施方案中,REM/T.O=0.8-2.6。In some embodiments, REM/T.O = 0.8-2.6.
在一些实施方案中,本发明的方法还包括铁水脱硫、脱磷、转炉脱碳、钢包顶渣改质、连铸、热轧、酸洗和冷轧中的一个或多个步骤。In some embodiments, the method of the present invention further includes one or more steps of molten iron desulfurization, dephosphorization, converter decarburization, ladle top slag modification, continuous casting, hot rolling, pickling and cold rolling.
本发明在RH(Ruhrstahl-Heraeus)炉真空脱氧结束,向钢液中加入稀土金属Ce和/或La,控制最终氧化物的组成为Ce 2O 3·Al 2O 3和/或La 2O 3·Al 2O 3,达到浇注顺行,改善氧化物类夹杂性能,降低含钛超低碳钢冷轧钢质缺陷的目的。 In the present invention, after the vacuum deoxidation of the RH (Ruhrstahl-Heraeus) furnace is completed, the rare earth metals Ce and/or La are added to the molten steel, and the final oxide composition is controlled to Ce 2 O 3 ·Al 2 O 3 and/or La 2 O 3 ·Al 2 O 3 , achieve the purpose of pouring forward, improve the performance of oxide inclusions, and reduce the defects of cold-rolled steel of titanium-containing ultra-low carbon steel.
本发明人研究发现,脱氧后的精炼后期,加入稀土金属(特指CeLa合金)至钢液中,稀土金属与未排除钢液的脱氧产物Al 2O 3发生如下反应: The inventors have discovered through research that in the late refining stage after deoxidation, when rare earth metals (especially CeLa alloys) are added to molten steel, the rare earth metals react with the deoxidation product Al 2 O 3 that does not exclude molten steel as follows:
2[Re]+(Al 2O 3)=(Re 2O 3·nAl 2O 3)+2[Al]   (1) 2[Re]+(Al 2 O 3 )=(Re 2 O 3 ·nAl 2 O 3 )+2[Al] (1)
这里n的可能取值为:11、1和0。与之对应,随着稀土加入量的增加,生成的反应产物依次为:Re 2O 3·11Al 2O 3(又称βAl 2O 3)、Re 2O 3·Al 2O 3和Re 2O 3。其中的生成物CeO 2·Al 2O 3,在1600℃钢液温度下呈液相,固相时边缘光滑无明显锐角,硬度与钢基体的接近。而常规铝脱氧钢中生成的Al 2O 3晶体属于α晶型,为六方晶胞结构,钢液温度下呈固相,边缘锐利,莫氏硬度为9级,远大于其他常见材料。在冷轧和后续冷加工时,与原始单一组分的Al 2O 3夹杂相比,本发明的钢中夹杂物Re 2O 3·Al 2O 3对钢板基体机械损伤的几率大大降低,从而减轻对钢板基体的损伤程度,改善成品表面和内部质量。本发明工艺生产的冷轧成品中典型夹杂物(主要组分确认为Re 2O 3·Al 2O 3)示于图2,同时图1给出了常规工艺生产的冷轧成品中单一脱氧产物Al 2O 3。与单一Al 2O 3相比,本发明控制生成的复合夹杂物,边缘相对光滑无明显棱角,经轧制本发明的夹杂物有沿轧制方向延展的趋势,塑性较好。 The possible values of n here are: 11, 1, and 0. Correspondingly, with the increase in the amount of rare earth added, the resulting reaction products are: Re 2 O 3 ·11Al 2 O 3 (also known as βAl 2 O 3 ), Re 2 O 3 ·Al 2 O 3 and Re 2 O 3 . The product, CeO 2 ·Al 2 O 3 , is in the liquid phase at the temperature of molten steel at 1600°C, and the edges are smooth in the solid phase without obvious acute angles, and the hardness is close to that of the steel matrix. The Al 2 O 3 crystals generated in conventional aluminum deoxidized steel belong to the α crystal type, with a hexagonal cell structure, and are solid at the temperature of molten steel, with sharp edges, and a Mohs hardness of 9, which is much larger than other common materials. During cold rolling and subsequent cold working, compared with the original single-component Al 2 O 3 inclusions, the inclusions Re 2 O 3 ·Al 2 O 3 in the steel of the present invention have a greatly reduced probability of mechanical damage to the steel plate substrate, thereby reducing The degree of damage to the steel plate substrate improves the surface and internal quality of the finished product. The typical inclusions in the cold-rolled product produced by the process of the present invention (the main component is confirmed as Re 2 O 3 ·Al 2 O 3 ) are shown in Figure 2, while Figure 1 shows the single deoxidized product in the cold-rolled product produced by the conventional process Al 2 O 3 . Compared with a single Al 2 O 3 , the composite inclusions produced under the control of the present invention have relatively smooth edges without obvious edges and corners. The inclusions of the present invention have a tendency to extend along the rolling direction after rolling, and have better plasticity.
本发明认为,含钛超低碳钢造成水口易结瘤、难以浇注的原因在于:一方面钢液中的Ti提高了Al 2O 3表层与钢液之间界面的润湿性,从而降低Al 2O 3夹杂物的大 小,而氧化铝夹杂物颗粒越小,越容易结瘤;另一方面更好的润湿性使得结瘤物与耐材间传热效果更佳,从而造成冷钢在结瘤位置的形成,促使结瘤程度加重。 The present invention believes that the reason why the titanium-containing ultra-low carbon steel is easy to nodule and difficult to cast is: on the one hand, the Ti in the molten steel improves the wettability of the interface between the Al 2 O 3 surface layer and the molten steel, thereby reducing Al The size of 2 O 3 inclusions, and the smaller the alumina inclusion particles, the easier it is to nodule; on the other hand, better wettability makes the heat transfer effect between nodule and refractory material better, resulting in cold steel The formation of the nodule position promotes the aggravation of the nodule.
本发明进行的试验结果表明:The test results carried out by the present invention show that:
当向含Ti的铝脱氧钢中加入稀土金属后,这种水口结瘤情况呈现加剧趋势,结晶器液面波动率加大,严重影响了连铸过程的顺行,降低了合格板坯的比例,恶化了成品质量。经多次试验发现,调整Ti的加入顺序,可以有效抑制钢液中Ti对钢液中Al 2O 3表面润湿性的影响,进而改善夹杂物的水口结瘤,保证结晶器液面平稳和连铸过程的顺行。图3为本发明冶炼含钛超低碳钢统计所得的结晶器液面波动率情况。常规工艺生产含钛超低碳钢的结晶器液面波动合格率、常规脱氧工艺(先Al后Ti脱氧工艺)结合稀土处理的结晶器液面波动率,一并示于图中。采用本发明技术后,结晶器液面波动与常规工艺处于同一水平。 When rare earth metals are added to Ti-containing aluminum deoxidized steel, this nozzle nodules tends to increase, and the fluctuation rate of the mold liquid level increases, which seriously affects the antegrade of the continuous casting process and reduces the proportion of qualified slabs. , Deteriorating the quality of the finished product. After many tests, it was found that adjusting the order of Ti addition can effectively suppress the influence of Ti in the molten steel on the surface wettability of Al 2 O 3 in the molten steel, thereby improving the nozzle nodules of inclusions and ensuring a stable and smooth liquid level in the mold. The antegrade of the continuous casting process. Fig. 3 shows the volatility of the crystallizer liquid level obtained by smelting titanium-containing ultra-low carbon steel according to the present invention. The crystallizer liquid level fluctuation qualification rate of the conventional process for producing titanium-containing ultra-low carbon steel, and the crystallizer level fluctuation rate of the conventional deoxidation process (Al first and Ti deoxidation process) combined with rare earth treatment are shown in the figure. After adopting the technology of the present invention, the liquid level fluctuation of the crystallizer is at the same level as that of the conventional process.
由于原理不同,导致本发明的具体技术方案和稀土金属加入量的控制方法与对比专利有显著差异。Due to the different principles, the specific technical scheme of the present invention and the method for controlling the amount of rare earth metal added are significantly different from those of the comparative patent.
本发明适用的钢种为超低碳钢类产品,即碳含量≤0.005wt%,且钢液组分中Al含量≥Ti含量,以保证稀土加入前钢液的终脱氧受钢液中Al所控制。The steel grades applicable to the present invention are ultra-low carbon steel products, that is, the carbon content is less than or equal to 0.005wt%, and the Al content in the molten steel component is greater than or equal to the Ti content to ensure that the final deoxidation of the molten steel before the addition of rare earths is affected by the Al in the molten steel. control.
本发明要求,进行真空脱碳处理,使得钢液中的碳位于成品要求值以下,真空处理脱碳结束,加入一定量的Ti对钢液进行脱氧,紧随其后,加入一定量的Al进行终脱氧,钢液循环一定时间;调整、添加其他合金元素,钢液循环一定时间;最后加入稀土金属Ce/La,钢液继续循环一定时间,钢液真空处理结束。The present invention requires vacuum decarburization treatment so that the carbon in the molten steel is below the required value of the finished product. After the vacuum treatment decarburization is completed, a certain amount of Ti is added to deoxidize the molten steel, followed by a certain amount of Al. Final deoxidation, molten steel circulates for a certain period of time; adjustment and addition of other alloying elements, molten steel circulates for a certain period of time; finally adding rare earth metal Ce/La, molten steel continues to circulate for a certain period of time, and the molten steel vacuum treatment ends.
加入稀土金属后,钢液循环时间为≥2min,使得钢中残留的夹杂物数量尽可能少。After adding rare earth metals, the molten steel circulation time is ≥2min, so that the number of residual inclusions in the steel is as small as possible.
本发明稀土加入量的上限确定为稀土加入质量(kg)与钢中总氧(ppm)比REM/T.O=3.0。当稀土加入量超过一定值后,钢液中的Al 2O 3可被全部还原,钢液中的氧全部以Re 2O 3形式存在,存在2种可能的不良后果:1)生成的单一稀土氧化物Re 2O 3,比重大,不易上浮;2)钢中游离态Re含量急剧上升,与耐材反应,污染钢液,严重情况下会导致塞棒或水口熔损,致使浇铸异常或中断。 The upper limit of the amount of rare earth added in the present invention is determined as the ratio of rare earth added mass (kg) to total oxygen (ppm) in the steel REM/TO=3.0. When the amount of rare earth added exceeds a certain value, the Al 2 O 3 in the molten steel can be completely reduced, and the oxygen in the molten steel is all in the form of Re 2 O 3 , and there are two possible adverse consequences: 1) a single rare earth produced The oxide Re 2 O 3 has a high specificity and is not easy to float; 2) The free Re content in the steel rises sharply, reacts with the refractory material and contaminates the molten steel. In severe cases, it will cause the stopper or nozzle to melt and cause the casting to be abnormal or interrupted.
稀土加入量的下限确定为REM/T.O=0.60。稀土加入量过低,钢中存在不稳定的Re 2O 3·11Al 2O 3(βAl 2O 3),甚至单一的Al 2O 3。随着温度的降低,中低温不稳定的βAl 2O 3分解,发生共析反应: The lower limit of the amount of rare earth added is determined as REM/TO=0.60. If the amount of rare earth added is too low, unstable Re 2 O 3 ·11Al 2 O 3 (βAl 2 O 3 ) or even single Al 2 O 3 exists in the steel. As the temperature decreases, βAl 2 O 3 , which is unstable at medium and low temperatures, decomposes and eutectoid reaction occurs:
Re 2O 3·11Al 2O 3(S)→Al 2O 3(S4)+Re 2O 3·Al 2O 3(S)   (2) Re 2 O 3 ·11Al 2 O 3 (S)→Al 2 O 3 (S4)+Re 2 O 3 ·Al 2 O 3 (S) (2)
生成两个稳定固相Al 2O 3(S4)和La 2O 3·Al 2O 3。这些残存于钢中的单一Al 2O 3,降低了稀土对Al 2O 3夹杂的改性效果,无法充分体现冷轧产品质量提高的冶金效果。 Two stable solid phases Al 2 O 3 (S4) and La 2 O 3 ·Al 2 O 3 are formed . The single Al 2 O 3 remaining in the steel reduces the modification effect of rare earth on Al 2 O 3 inclusions, and cannot fully reflect the metallurgical effect of improving the quality of cold-rolled products.
钢液中加Al后,钢液纯循环时间要求≥3min,以保证钢中脱氧产物Al 2O 3充分上浮至钢包顶渣,使得大部分生成的夹杂物上浮至钢包顶渣。 After adding Al to the molten steel, the pure circulation time of the molten steel is required to be ≥3min to ensure that the deoxidized product Al 2 O 3 in the steel fully floats to the top slag of the ladle, so that most of the generated inclusions float to the top slag of the ladle.
关于Ti的添加,其加入量以拟制造的该规格的成品钢中Ti的下限值作为加入标准。例如,某规格的含钛超低碳成品钢中,Ti含量在0.02-0.03%的范围内,则真空处理脱碳后Ti的加入量为该Ti含量范围(即0.02-0.03%)的下限值,即0.02%。Regarding the addition of Ti, the addition amount is based on the lower limit of Ti in the finished steel of the specification to be manufactured as the addition standard. For example, in a certain specification of titanium-containing ultra-low carbon finished steel, the Ti content is in the range of 0.02-0.03%, and the amount of Ti added after vacuum treatment decarburization is the lower limit of the Ti content range (ie 0.02-0.03%) Value, which is 0.02%.
关于Al的添加,其加入量以拟制造的该规格的成品钢中Al含量范围的中值作为加入标准。例如,某规格的含钛超低碳钢中Al的含量范围为0.06-0.09%,则真空处理脱碳后Al的加入量为该Al含量范围(即0.06-0.09%)的中间值,即0.075%。Regarding the addition of Al, the addition amount is based on the middle value of the Al content range in the finished steel of the specification to be manufactured as the addition standard. For example, the Al content of a certain specification of titanium-containing ultra-low carbon steel is 0.06-0.09%, and the amount of Al added after vacuum treatment decarburization is the middle value of the Al content range (ie 0.06-0.09%), that is, 0.075 %.
本发明的有益效果:The beneficial effects of the present invention:
与常规工艺相比,本发明提出的含钛超低碳钢冷轧钢质缺陷的控制方法具有以下工艺效果:Compared with conventional processes, the method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel provided by the present invention has the following process effects:
1)钢中的氧化物夹杂组成由单纯的Al 2O 3转变为Re 2O 3·Al 2O 31) The composition of oxide inclusions in steel changes from pure Al 2 O 3 to Re 2 O 3 ·Al 2 O 3 ;
2)冷轧钢质缺陷封锁率,降低幅度>45%;2) The blocking rate of cold-rolled steel defects is reduced by >45%;
3)Al 2O 3所引起的冷轧钢质缺陷封锁率,降低幅度>90%; 3) The blocking rate of cold-rolled steel defects caused by Al 2 O 3 is reduced by >90%;
4)结晶器液面波动±5mm和±3mm符合率分别>85%和>25%,与常规工艺相当。4) The coincidence rate of crystallizer liquid level fluctuation ±5mm and ±3mm are >85% and >25% respectively, which are equivalent to the conventional process.
本发明上述工艺控制,对最终成品质量改善显著。The above-mentioned process control of the present invention significantly improves the quality of the final product.
附图说明Description of the drawings
图1为常规工艺下冷轧成品钢中典型夹杂物。Figure 1 shows typical inclusions in cold-rolled finished steel under conventional processes.
图2为本发明冷轧成品钢中典型夹杂物。Figure 2 shows typical inclusions in the cold-rolled finished steel of the present invention.
图3为结晶器液面波动符合率示意图。Figure 3 is a schematic diagram of the coincidence rate of crystallizer liquid level fluctuation.
具体实施方式detailed description
本发明所发明的含钛超低碳钢氧化物夹杂控制方法,能够保证炼钢生产的稳定顺行,改变钢中氧化物夹杂的物性,从而降低最终成品的冷轧钢质缺陷封锁率,显 著地改善超低碳钢产品质量。The method for controlling oxide inclusions in titanium-containing ultra-low-carbon steel invented by the present invention can ensure stable and anterograde steelmaking production, change the physical properties of oxide inclusions in the steel, and reduce the blocking rate of cold-rolled steel defects in the final product. Improve the quality of ultra-low carbon steel products.
针对含钛超低碳钢的生产,本发明所采用的工艺路径为:铁水脱硫、脱磷-转炉脱碳-出钢,钢包顶渣改质-真空脱碳、Ti脱氧、加Al和成分微调-加入稀土金属-连铸-热轧-酸洗-冷轧。For the production of titanium-containing ultra-low carbon steel, the process path adopted by the present invention is: hot metal desulfurization, dephosphorization-converter decarburization-steel tapping, ladle top slag modification-vacuum decarburization, Ti deoxidation, Al addition and fine adjustment of composition -Add rare earth metal-continuous casting-hot rolling-pickling-cold rolling.
采用本发明冶炼的典型炉次如下:The typical furnaces smelted by the present invention are as follows:
转炉吹炼结束,[%C]=280ppm,[%O]=550ppm;挡渣出钢,出钢初期加入石灰3.5kg/t钢,末期加入铝渣0.90kg/t钢;真空处理前钢包顶渣成分(%FeO)+(%MnO)≤6.50,[(%CaO)+(%MgO)]/(%Al 2O 3)=1.70,渣厚110mm;真空脱碳结束,加入Ti对钢液进行脱氧、随后加入Al,钢液循环9min;合金化,调整钢液成份至规格范围,[%C]=12ppm,[%Si]=0.0065,[%Mn]=0.12,[%Al]=0.025,[%Ti]=0.025,循环一定时间;稀土加入后,钢液循环5min,精炼结束;连铸,随后热轧、酸洗和冷轧;REM/T.O=1.35; After converter blowing, [%C]=280ppm, [%O]=550ppm; stop slag tapping, add lime 3.5kg/t steel at the beginning of tapping, add aluminum slag 0.90kg/t steel at the end; ladle top before vacuum treatment Slag composition (%FeO)+(%MnO)≤6.50, [(%CaO)+(%MgO)]/(%Al 2 O 3 )=1.70, slag thickness 110mm; after vacuum decarburization, add Ti to molten steel Deoxidize, then add Al, circulate the molten steel for 9 minutes; alloy, adjust the composition of the molten steel to the specification range, [%C]=12ppm, [%Si]=0.065, [%Mn]=0.12, [%Al]=0.025 , [%Ti] = 0.025, cycle for a certain period of time; after the rare earth is added, the molten steel is circulated for 5 minutes, and the refining ends; continuous casting, followed by hot rolling, pickling and cold rolling; REM/TO=1.35;
工艺效果:对于最终工艺效果的判断,以同中间包且相邻的常规炉次作为比较对象,本发明实施例冷轧钢质缺陷的封锁率为1.55%,其中Al 2O 3所致的钢质缺陷为0,相邻前后炉次冷轧钢质缺陷封锁率分别为3.25%和2.95%,Al 2O 3所致的分别1.55%和0.75%。 Process effect: For the judgment of the final process effect, the conventional heats adjacent to the same tundish are used as the comparison object. The cold-rolled steel defect blocking rate of the embodiment of the present invention is 1.55%, among which the steel caused by Al 2 O 3 The quality defect is 0, the blocking rate of the cold-rolled steel defects of the adjacent heats is 3.25% and 2.95%, respectively, and the defects caused by Al 2 O 3 are 1.55% and 0.75% respectively.
表1为实际生产中一些应用本发明方法案例的情况对比。Table 1 is a comparison of some cases of applying the method of the present invention in actual production.
本发明针对含钛超低碳钢冷轧产品,开发的冷轧钢质缺陷控制方法,有效地改善了钢中脱氧夹杂物的性能,同时能够稳定钢液的浇注顺行,进而降低了冷轧成品钢质缺陷的发生率,适用于含钛超低碳钢冷轧产品质量改善,在炼钢厂具有推广应用价值。Aiming at the cold-rolled products of titanium-containing ultra-low carbon steel, the present invention has developed a cold-rolled steel defect control method, which effectively improves the performance of deoxidizing inclusions in the steel, and at the same time can stabilize the pouring of molten steel in order, thereby reducing the cold rolling The incidence of defects in finished steel is suitable for the improvement of the quality of cold-rolled products of ultra-low carbon steel containing titanium, and has promotion and application value in steel plants.
表1Table 1
Figure PCTCN2020110757-appb-000001
Figure PCTCN2020110757-appb-000001

Claims (9)

  1. 一种含钛超低碳钢冷轧钢质缺陷的控制方法,其特征是,所述含钛超低碳钢的成分重量百分比为:C≤0.005%,Si≤0.05%,Mn 0.05-0.3%,Al 0.02-0.1%,Ti 0.008-0.05%,P≤0.05%,S≤0.02%,N≤0.003%,T.O 0.0010~40%,其余为Fe和不可避免杂质,且,Al含量≥Ti含量;所述方法包括:A method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel, characterized in that the composition weight percentage of the titanium-containing ultra-low carbon steel is: C≤0.005%, Si≤0.05%, Mn 0.05-0.3% , Al 0.02-0.1%, Ti 0.008-0.05%, P≤0.05%, S≤0.02%, N≤0.003%, TO 0.0010-40%, the rest are Fe and inevitable impurities, and the Al content is greater than or equal to the Ti content; The method includes:
    RH真空脱碳结束后,先加入Ti,Ti的加入量为成品规格的Ti含量范围的下限值;再添加Al,Al的加入量为成品规格的Al含量范围的中间值;然后钢液循环,时间≥3min;After RH vacuum decarburization is completed, Ti is added first, the amount of Ti added is the lower limit of the Ti content range of the finished product specification; then Al is added, and the amount of Al added is the middle value of the Al content range of the finished product specification; then the molten steel is circulated , Time≥3min;
    按照成品规格添加其他合金元素和/或调整钢液成分,钢液循环,时间≥2min;Add other alloy elements and/or adjust the composition of the molten steel according to the specifications of the finished product, and the molten steel circulates for a time ≥2min;
    向钢液中加入稀土金属Ce和/或La,加入量控制为REM/T.O=0.6-3.0,其中,稀土金属REM的加入量以质量计单位为kg,钢中总氧T.O单位为ppm;钢液循环,时间≥2min,最终钢液中生成氧化物Ce 2O 3·Al 2O 3和/或La 2O 3·Al 2O 3,达到浇注顺行。 Add the rare earth metal Ce and/or La to the molten steel, and the addition amount is controlled to REM/TO=0.6-3.0, where the addition amount of the rare earth metal REM is in kg by mass, and the total oxygen TO in the steel is in ppm; steel Liquid circulation, time ≥ 2min, and finally oxides Ce 2 O 3 ·Al 2 O 3 and/or La 2 O 3 ·Al 2 O 3 are generated in molten steel, and the pouring is in order.
  2. 如权利要求1所述的含钛超低碳钢冷轧钢质缺陷的控制方法,其特征是,所述稀土金属的成分为Ce和任选的La。The method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel according to claim 1, wherein the composition of the rare earth metal is Ce and optionally La.
  3. 如权利要求1所述的含钛超低碳钢冷轧钢质缺陷的控制方法,其特征是,所述稀土金属的成分质量百分比为:Ce 60-70%,La 30-40%。The method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel according to claim 1, wherein the composition mass percentage of the rare earth metal is: Ce 60-70%, La 30-40%.
  4. 如权利要求1所述的含钛超低碳钢冷轧钢质缺陷的控制方法,其特征是,加入Al后,钢液循环时间≥5min。The method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel according to claim 1, wherein after Al is added, the molten steel circulation time is ≥5 min.
  5. 如权利要求1所述的含钛超低碳钢冷轧钢质缺陷的控制方法,其特征是,加入REM后,钢液循环时间≥3min。The method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel according to claim 1, characterized in that, after adding REM, the liquid steel circulation time is ≥3min.
  6. 如权利要求1所述的含钛超低碳钢冷轧钢质缺陷的控制方法,其特征是,REM/T.O=0.8-2.6。The method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel according to claim 1, wherein REM/T.O=0.8-2.6.
  7. 如权利要求1所述的含钛超低碳钢冷轧钢质缺陷的控制方法,其特征是,所述方法还包括铁水脱硫、脱磷、转炉脱碳、钢包顶渣改质、连铸、热轧、酸洗和冷轧中的一个或多个步骤。The method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel according to claim 1, wherein the method further comprises hot metal desulfurization, dephosphorization, converter decarburization, ladle top slag modification, continuous casting, One or more steps of hot rolling, pickling and cold rolling.
  8. 如权利要求1所述的含钛超低碳钢冷轧钢质缺陷的控制方法,其特征是,所述方法中,加入Ti对钢液进行脱氧,紧随其后,加入Al进行终脱氧。The method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel according to claim 1, characterized in that, in the method, Ti is added to deoxidize the molten steel, and then Al is added for final deoxidation.
  9. 如权利要求1所述的含钛超低碳钢冷轧钢质缺陷的控制方法,其特征是,所述含钛超低碳钢中,Al的含量0.05-0.1%。The method for controlling cold-rolled steel defects of titanium-containing ultra-low carbon steel according to claim 1, wherein the content of Al in the titanium-containing ultra-low carbon steel is 0.05-0.1%.
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002194497A (en) * 2000-12-21 2002-07-10 Sumitomo Metal Ind Ltd Si KILLED STEEL AND ITS PRODUCTION METHOD
JP2014109056A (en) * 2012-11-30 2014-06-12 Nippon Steel & Sumitomo Metal High strength steel sheet excellent in extension flange property and bendability, method for smelting molten steel for the steel sheet
CN108754293A (en) * 2018-06-20 2018-11-06 张家港广大特材股份有限公司 A kind of vacuum induction melting technique of GH2132 alloys
CN109402321A (en) * 2018-09-29 2019-03-01 宝山钢铁股份有限公司 The control method that oxide is mingled in a kind of ultra-low-carbon steel

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4103513B2 (en) * 2002-09-11 2008-06-18 Jfeスチール株式会社 Extremely low carbon steel wire rod with excellent cold workability and magnetic properties

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002194497A (en) * 2000-12-21 2002-07-10 Sumitomo Metal Ind Ltd Si KILLED STEEL AND ITS PRODUCTION METHOD
JP2014109056A (en) * 2012-11-30 2014-06-12 Nippon Steel & Sumitomo Metal High strength steel sheet excellent in extension flange property and bendability, method for smelting molten steel for the steel sheet
CN108754293A (en) * 2018-06-20 2018-11-06 张家港广大特材股份有限公司 A kind of vacuum induction melting technique of GH2132 alloys
CN109402321A (en) * 2018-09-29 2019-03-01 宝山钢铁股份有限公司 The control method that oxide is mingled in a kind of ultra-low-carbon steel

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
JIANG, MAOFA, ZHANG ZHI-XIANG, WANG DE-YONG, LIU JUN: "Inclusions in Characteristic of Ti/A1 Deoxidation Steel and the Analysis of Nozzle Clogging Problem", INDUSTRIAL HEATING, vol. 40, no. 4, 30 August 2011 (2011-08-30), pages 1 - 4, XP055787395, ISSN: 1002-1639 *
SHANG, DELI ET AL.: "Applied Research of Aluminum and Titanium Deoxidation Based on Oxide Metallurgy Technology", JOURNAL OF UNIVERSITY OF SCIENCE AND TECHNOLOGY BEIJING, vol. 32, no. 11, 30 November 2010 (2010-11-30), pages 1 - 5, XP055787389 *

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