Control method for improving homogeneity of heavy rail steel

Abstract

The invention discloses a control method for improving homogeneity of heavy rail steel, and belongs to the field of iron and steel metallurgy. The control method adopts the following steps, for controlling emphatically in a continuous casting stage, that secondary cooling electromagnetic stirring is adopted for continuous casting electromagnetic stirring, a specific installation position is an interval of 5 - 6 m from a steel liquid level of the crystallizer, and the intensity of a stirring magnetic field is controlled to be 200 * 10 <-4> - 250 * 10 <-4> T; the superheat degree of tundish casting molten steel is executed at the temperature of 35 - 45 DEG C; the amount of cooling water of continuous casting secondary cooling executed at specific water flow of 0. 28 - 0. 30 L / kg; and the reduction amount of a solidification tail end is not less than 10.0 mm. According to the above parameters, a solidification structure of a casting blank is well controlled, columnar crystal is developed,a crystal rod is fine and compact, and the area of an isometric crystal (crystal particles are short and crystal rods are thick) area is reduced; the segregation curve of evolution of C element of the casting blank evolves gently, no larger negative and positive segregation alternation exists, the segregation degree of the C element of a steel rail is small, the homogeneity of the steel rail is high, the center deflection line of a rail web is small and short, the center segregation control is good, and the effective improvement of the homogeneity of the heavy rail steel is realized.

Description

technical field [0001] The invention relates to the field of iron and steel metallurgy, in particular to a method for controlling the homogeneity improvement of heavy rail steel. Background technique [0002] Steel rails are the main components of railway tracks. During railway transportation, to provide effective support and guidance for locomotives, they need to bear huge vertical pressure from wheels. Based on the development needs of my country's infrastructure construction, railway transportation is developing at a rapid speed, and it is becoming more and more high-speed and heavy-duty. This undoubtedly puts forward more stringent requirements on the quality of rails. The improvement of rail quality is reflected in the quality control level of steel itself to a certain extent, such as high homogeneity, high cleanliness, and high compositional precision. Among them, the homogeneity of the rail (the smaller the degree of segregation, the higher the homogeneity of the ra...

AI Technical Summary

Problems solved by technology

Among them, the homogeneity of the rail (the smaller the degree of segregation, the higher the homogeneity of the rail) affects the uniformity of the steel structure. Severe segregation will affect the welding performance of the rail parent material and the rail, and then affect the service and use of the rail.