High-drawing-speed sheet billet peritectic steel continuous casting crystallizer casting powder and preparation method thereof

Abstract

The invention discloses high-drawing-speed sheet billet peritectic steel continuous casting crystallizer casting powder and a preparation method thereof. According to the raw material formula, the casting powder comprises, by weight, 57%-60% of aedelforsite, 7%-9% of fluorite, 8%-10% of sodium carbonate, 0%-2% of lithium carbonate, 7%-9% of glass powder, 3%-5% of bauxite, 4.5%-4.7% of carbon black and 5%-5.5% of graphite. According to the chemical composition, the casting powder comprises, by weight, 36.8%-38.3% of calcium oxide, 23.5%-25% of silicon dioxide, 2.9%-3.4% of magnesium oxide, 3.1%-3.7% of aluminum oxide, 4%-4.2% of sodium oxide, 0-1.3% of lithium oxide and 7.8%-8.5% of fixed carbon, casting powder basicity, namely CaO / SiO2, is 1.50-1.54, the melting point is 1,050 DEG C-1,100 DEG C, and the viscosity is 0.2-0.25 Pa.s at 1,300 DEG C. The casting powder can effectively solve the problems that during continuous casting, crusting and slag inclusion of casting powder of peritectic steel happen, and the surface of a casting blank cracks and is prone to breakout by sticking. Besides, the casting powder has the advantages that slag melting in a crystallizer is uniform and stable, and the surface quality of the casting blank is good and not prone to breakout by sticking.

Description

technical field [0001] The invention belongs to the technical field of steelmaking auxiliary materials, and in particular relates to a high-speed thin slab peritectic steel continuous casting mold mold powder and a preparation method thereof. Background technique [0002] The carbon content of peritectic steel is generally 0.08-0.18%, and its main characteristics are: peritectic steel belongs to crack sensitive steel. In the process of phase transformation, large volume shrinkage can easily produce surface cracks, and when solidifying in the crystallizer, local stress concentration occurs due to uneven heat transfer, which may cause longitudinal cracks in this part. Leakage accidents are prone to occur, and it is a steel type that is difficult to cast in continuous casting. [0003] The carbon content of peritectic steel is low, which belongs to typical medium carbon steel, and the temperature of peritectic reaction is high, the reaction speed is slow, and the chemical comp...

AI Technical Summary

Problems solved by technology

[0003] The carbon content of peritectic steel is low, which belongs to typical medium carbon steel, and the temperature of peritectic reaction is high, the reaction speed is slow, and the chemical composition is difficult to achieve uniformity, so segregation is easy to occur, and it is difficult to eliminate, and the material is easy to break

[0004] In summary, due to these characteristics of peritectic steel, problems such as cracks on the surface of the slab and bonded breakouts are prone to occur during the casting process.