A low-cost high-carbon chromium bearing steel smelting method

Abstract

The invention discloses a smelting method for low-cost high-carbon chromium bearing steel, which comprises (1) a primary smelting process in a converter: the C content at the end point of blowing is 0.05-0.15wt%, and the end point P content is less than or equal to 0.015wt%; Steel temperature 1620~1650℃; (2) LF refining process: total refining time 40~55min, refining slag basicity value 4~8; (3) RH vacuum refining process: vacuum degree ≤100Pa, refining time 20~30min; (4) Continuous casting process: the temperature of molten steel in the tundish is 1475-1485°C, the continuous casting speed is 0.60-0.75m / min, and the end of the liquid core of the casting billet is lightly pressed, and the reduction amount is 6-10mm. The invention ensures that the non-metallic inclusion rating of the finished product meets the standard requirements while realizing the high-efficiency, fast-paced and low-cost production of the bearing steel.

Description

technical field [0001] The invention belongs to the technical field of metallurgy and relates to a low-cost high-carbon chromium bearing steel smelting method. Background technique [0002] Bearing rolling elements are an important part of bearings. Their parts bear extremely strong point loads or surface loads in extremely harsh working environments. They are required to have wear resistance, corrosion resistance, and high hardness. Unique work requirements determine the characteristics of steel types In order to meet the corresponding performance, the raw material of the bearing rolling body - bearing steel must have the characteristics of high purity, uniform density at low magnification, and uniform distribution of carbides. [0003] The preparation process of traditional high-carbon chromium bearing rolling element steel: molten iron pretreatment → primary smelting in converter or electric furnace → LF refining → VD or RH refining → continuous casting or die casting → r...

AI Technical Summary

Problems solved by technology

However, the bearing steel prepared by this method still has the problem of uneven distribution of non-metallic inclusions, and the performance of the steel is difficult to meet the strict standard requirements

[0006] Patent CN 108676952 A discloses a preparation method of bearing steel produced by converter process. The preparation process of this method is relatively complicated. The converter requires high carbon at the end point, and it is difficult to achieve high carbon, low phosphorus and stable temperature hit on site; Standard operation requirements; RH high vacuum degree is high, pure degassing time is short, which is not good for inclusion control

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