Anti-bonding bleed-out continuous casting covering slag

Abstract

The invention relates to a covering powder material, in particular to an anti-bonding bleed-out continuous casting covering slag. The components of the anti-bonding bleed-out continuous casting covering slag in weight percent are as follow: 2-8% of Al2O3, 2-7% of F, 4-8% of Na2O, less than 4% of Li2O, 2-15% of B2O3, 0.7-3% of C, less than 3% of impurities carried in by raw materials, and balance of CaO and SiO2 with the weight ratio of CaO / SiO2 being 0.5-0.8. The properties of the covering slag are as follows: solidification temperature is less then 980 DEG C, viscosity at 1300 DEG C is 0.2-0.5Pa.s, and no crystal is precipitated during solidification. The usabilities of the covering slag are as follows: consumption rate is larger than or equal to 0.4kg / t steel, and the thickness of melt slag layer is 10-16mm. The anti-bonding bleed-out continuous casting covering slag in the invention can prevent the phenomenon of bonding bleed-out, improve operation rate of continuous casting machine, and reduce cost and accidents.

Description

technical field

[0001] The invention relates to a protective powder used in metal continuous casting, in particular to anti-bonding breakout continuous casting protective powder for steelmaking. Background technique

[0002] Continuous casting mold flux is a powdery or small granular steelmaking auxiliary material used to cover the surface of molten steel in the mold of a continuous casting machine. It has many functions such as thermal insulation, preventing oxidation of molten steel, absorbing inclusions, lubricating and controlling heat transfer, etc., and plays an important role in the quality of casting slabs.

[0003] When mold slag covers the surface of molten steel, a certain thickness of liquid slag layer must be formed between molten steel and solid mold slag, so as to effectively prevent the entry of air and accommodate more foreign inclusions, and provide a gap between the billet and the copper plate of the water-cooled crystallizer. Sufficient liquid slag is pr...