TiO2 containing high-aluminum steel protection slag and application thereof

Abstract

The invention discloses TiO2 containing high-aluminum steel protection slag. The TiO2 containing high-aluminum steel protection slag comprises following oxides including, by mass percent, 30%-45% of CaO, 16%-24.5% of Al2O3, 8%-16% of SiO2, 8%-15% of Na2O, 1%-5% of Li2O, 2%-6% of MgO, 3%-7% of BaO, 6%-10% of F<-> and 2.7%-7% of TiO2, and (CaO+BaO)/Al2O3 ranges from 1.0 to 2.1. The protection slag is low in melting point and viscosity, and the crystallization property is good. The protection slag is particularly suitable for continuous casting of high-aluminum steel with the Al mass percent content ranging from 1.5% to 2.5%. When the protection slag is used, the slag steel reaction degree in the continuous casting process can be effectively weakened, and the crystallization property and the lubricating property of the protection slag in the continuous casting process become more stable; and the probability that concaves, cracks, inclusions and other quality defects happen to the surfaces of casting blanks is greatly reduced.

Description

Technical field [0001] The invention belongs to the field of steel smelting and continuous casting, and relates to a high-aluminum steel mold flux with good physical and chemical properties and a control technology for inhibiting the slag-steel reaction in the continuous casting process. Background technique [0002] With the rapid development of the automobile industry and the electrical industry, the development of advanced high-strength steel has received extensive attention. As a very important additive element in steel, Al can significantly improve the properties of steel grades. For example, the Al content in TRIP steel is between 0.6-1.7, which can make the steel matrix form a more stable multiphase structure. It can improve the galvanizing effect of the cast slab surface. The Al content of 20Mn23AlV austenitic non-magnetic steel can reach 1.5-2.5%, which can effectively reduce the transformation of martensite in Fe-Mn, and can also improve the problem of work hardening. ...

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Problems solved by technology

Judging from the situation of literature retrieval, the patent with the publication number CN105436446A "A kind of mold powder for high manganese and high aluminum steel and its preparation method" discloses a CaO-SiO 2 It is high manganese and high aluminum steel mold powder and its preparation method, but the powder does not take into account the Al in the molten steel and the SiO in the slag during the continuous casting process 2 , MnO and B 2 o 3 Slag-steel reaction occurs, which deteriorates the physical and chemical properties of mold slag, resulting in cracks on the surface of the slab obtained

[0007] (2) The newly proposed non-reactive mold flux, which is based on CaO-Al 2 o 3 A new slag system based on the system, which contains a relatively high content of Al 2 o 3 The content is higher, while SiO 2 The content of slag is very low, which greatly reduces the driving force of the slag-steel reaction and greatly limits the progress of the slag-steel reaction

But SiO in slag 2 The content is too low, Al 2 o 3 If the content is too high, the melting point of the mold slag will be high, and the glass performance of the slag will be weakened, resulting in too strong crystallization performance, which is not conducive to the melting of the mold slag, and will greatly weaken the heat transfer control performance and lubricating performance of the mold slag.

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