Low alloy steel mold flux for chamfer crystallizer

Abstract

The invention relates to a low alloy steel mold flux for a chamfering crystallizer, and belongs to the field of metallurgical auxiliary materials for steel making, the low alloy steel mold flux for the chamfer crystallizer is prepared from the following chemical components: 32 to 39 parts by weight of CaO, 30.5 to 32. 5 parts by weight of SiO2, 2 to 6 parts by weight of Al2O3, more than 0 and lessthan or equal to 3 parts by weight of Fe2O3, 2 to 12 parts by weight of MgO, more than 0 and less than or equal to 8 parts by weight of Na2O, 4 to 7. 5 parts by weight of F and 4 to 8 parts by weightof C, the mold flux has the characteristics of low alkalinity, high melting point and low viscosity, and can effectively solve the problem of transverse cracks in low alloy steel billets such as vanadium, niobium and titanium.

Description

technical field [0001] The invention relates to the field of metallurgical auxiliary materials for steelmaking, and in particular to a low-alloy steel mold slag for chamfering crystallizers. Background technique [0002] In recent years, metallurgists have carried out in-depth research on microalloying elements, especially vanadium, niobium and titanium, and developed more and more steel types. However, with the addition of vanadium, niobium and titanium, continuous casting slabs are prone to edge transverse cracks. Crack defects, which have a lot to do with the characteristics of low-alloy steel grades; during the production process, the relevant steelmaking and continuous casting production processes have been adjusted, and the defect rate is still high. [0003] At present, most of the domestic steel mills are reforming the copper plate of the crystallizer, relying on the chamfering mold technology to improve the transverse crack defect. Big changes, among which the char...

AI Technical Summary

Problems solved by technology

[0004] 1. The carbon and nitrogen compounds produced by vanadium, niobium, titanium and other microalloying elements in the continuous casting process precipitate along the γ grain boundary, and the precipitates aggravate the initiation and development of cracks along the grain boundary. Coarse, the enrichment of microalloy compounds is more obvious, so that the high-temperature fracture strength of the proeutectoid ferrite zone on the columnar grain boundary decreases sharply, coupled with the notch effect at the trough, so microalloys are prone to transverse crack defects