Intermediate frequency furnace smelting and electric kiln heat treatment process for cast steel with grade of G20Mn5N

Abstract

The invention discloses a novel intermediate frequency furnace smelting and electric kiln heat treatment process for cast steel with the grade of G20Mn5N. The process adopts a heat treatment method ofcontrolling narrow intervals of chemical components in each stage of a smelting process, pre-deoxidizing and finally deoxidizing aluminum wires in a furnace, newly adding a self-made molten steel purifying agent, optimizing a material adding mode and adding amount, pre-normalizing, normalizing and tempering, purifies molten steel, improves the metallographic structure, and optimizes the smeltingand heat treatment process through a series of control means. In conclusion, after the novel intermediate frequency furnace smelting and electric kiln heat treatment process is adopted, G20Mn5N chemical components are qualified, non-metallic inclusions and the grain size are qualified, test bars and real objects meet the new mechanical performance requirements, and at present, batch production ofthe steel grade is achieved, and the expected design target is achieved.

Description

technical field [0001] The invention relates to an intermediate frequency furnace smelting and electric kiln heat treatment process for cast steel grade G20Mn5N. Background technique [0002] With the development of the metal material industry and the demand for the use of cast steel materials in vehicle rail transit, the linear motor vehicle bogie suspension beam purchased by CRRC Qingdao Sifang Co., Ltd. puts forward higher requirements for the mechanical properties of the cast steel grade G20Mn5N. According to the EN10293 standard, the chemical composition of G20Mn5 is shown in Table 1. Two heat treatments, normalizing and tempering, can be adopted. The mechanical performance requirements are shown in Table 2. The chemical composition of G20Mn5N purchased by CRRC Qingdao Sifang Co., Ltd. is shown in Table 1. The performance requirements are shown in Table 3, non-metallic inclusions should meet Table 4, and the qualified grade of grain size is finer than or equal to grade ...

AI Technical Summary

Problems solved by technology

The usual intermediate frequency furnace smelting and electric kiln heat treatment process cannot guarantee that the mechanical properties and non-metallic inclusions meet the standard requirements, and the mechanical properties required by customers are higher than the standard, and the purity of molten steel must be improved. Therefore, the intermediate frequency furnace smelting and electric kiln heat treatment process Optimization, a new intermediate frequency furnace smelting and electric kiln heat treatment process for cast steel grade G20Mn5N was proposed to ensure that the chemical composition, higher mechanical properties, non-metallic inclusions and grain size requirements of cast steel grade G20Mn5N were met

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