Continuous casting mold flux for high-carbon cutting mold steel

Abstract

The invention provides continuous casting mold flux for high-carbon cutting mold steel. The continuous casting mold flux comprises the following chemical components in percentage by weight: 28.0-29.0% of CaO, 2-5% of MgO, 31.0-33.0% of SiO2, 4-5% of Al2O3, 8.0-9.0% of Na2O, 9-10% of F, 1.5-2.5% of LiO2, 2.0-2.8% of elemental carbon F.c and the balance of ash content I.L; and the alkalinity R of the mold flux is 0.80-0.95%. The continuous casting mold flux has the beneficial effects that by adjusting the components of the mold flux affecting production characteristics of the cutting mold steel and particularly by adjusting the contents of the flux, F, LiO2 and elemental carbon, the melting point of the mold flux is lowered so as to achieve stable dynamic balance between the melting speed and the inflow speed of the mold flux during the continuous casting process, thus improving the fluidity and crystallization speed of the mold flux during the casting process of the cutting mold steel, lowering the melting speed of the mold flux, realizing stable continuous casting production of the cutting mold steel, ensuring lubricating property of an initial shell of a plate blank in a crystallizer, preventing adhesion or bleed-out accidents caused by slag breakage, and realizing stable and smooth production of the high-carbon cutting mold steel.

Description

technical field [0001] The invention relates to metallurgical auxiliary materials for continuous casting, in particular to continuous casting mold slag for high-carbon knife die steel. Background technique [0002] Continuous casting mold slag is a synthetic auxiliary material added to the crystallizer and covered on the surface of molten steel during the continuous casting of molten steel. It will contain CaO, SiO 2 Raw materials, fluoride and Na-containing materials are mixed in appropriate proportions, melted at high temperature to make pre-melted powder, and then mixed with certain C-quality materials and various additives, and made after mixing and drying. [0003] Mold slag mainly plays the functions of lubrication, heat insulation, prevention of secondary oxidation, and adsorption of inclusions in molten steel. A four-layer structure of powder slag layer, sintering layer, carbon-rich layer, and liquid slag layer is formed on the liquid steel surface in the crystalliz...

AI Technical Summary

Problems solved by technology

[0005] The unit consumption of mold slag is only 0.20-0.28Kg / t.s, which is at the lower limit of the minimum unit consumption stipulated in the continuous casting process technical standard. The thickness of the molten layer of mold slag is generally 8-15mm when pouring the first furnace, and it is necessary to At the same time, the molten layer is sticky and the fluidity is poor, and the liquid mold slag flows into the meniscus of the crystallizer even less, sometimes even causing slag breaking, often causing bonding or even cohesive breakouts, which seriously affects stable production