Preparation method of Cu-containing ultra-low titanium bearing steel GCr15-J

Abstract

The invention belongs to the field of metallurgy, and particularly relates to a preparation method of the Cu-containing ultralow-titanium bearing steel GCr15-J. According to the technical scheme, themethod comprises the following steps of (1) carrying out the EBT electric furnace smelting, specifically, adopting the scrap steel and molten iron as the furnace burden, wherein the scrap steel is high-quality scrap steel without impurity elements, and the proportion is 15-35%; the molten iron is low-phosphorus and low-sulfur molten iron, and the proportion is 65-85%; (2) carrying out LF refining,specifically, electrifying to slag for 10 min, and salvaging the slag after slagging; then feeding an Al wire; adding a diffusion deoxidizing agent; adjusting the components to a target after deoxidation; 3) carrying out VD vacuum degassing, adjusting the Al to 0.025%-0.035%, wherein the VD entering temperature is 1570-1610 DEG C, the vacuum degree reaches 100 Pa or below, and the holding time islonger than or equal to 20 min; 4) continuously casting, specifically, manufacturing the square billets through a continuous casting machine; and 5) heating and rolling, rolling a casting blank intoa bar. According to the present invention, the indexes of low oxygen, low calcium, low inclusion content and the like of the bearing steel are guaranteed, and it is also guaranteed that the titanium content of the bearing steel reaches the quality level of the special-grade high-quality bearing steel.

Description

technical field [0001] The invention belongs to the field of metallurgy, and in particular relates to a preparation method of Cu-containing ultra-low titanium bearing steel GCr15-J. Background technique [0002] Bearing steel is an important steel material. The nitrides in bearing steel mainly exist in TiN or TiCN. Titanium nitride is a hard and brittle inclusion, which is very harmful to the fatigue life of steel. Now downstream users are interested in metallurgy. The internal metallurgical quality requirements of bearing steel produced by enterprises are becoming more and more stringent (such as inclusions, carbides, etc.), especially for the size, quantity and distribution of large-grain inclusions TiN in steel. This is because ① titanium nitride ( TiN) inclusions destroy the continuity of the steel matrix, and stress concentration is easy to occur under the condition of external deformation force; The formation of initial cracks is the fatigue source of further fatigue ...

AI Technical Summary

Problems solved by technology

[0004] Nowadays, the smelting method of using low-titanium ferrochrome to produce low-titanium bearing steel is generally adopted, and the steel is relatively easy to realize, but to realize the production of ultra-low titanium bearing steel (Ti≤15ppm), only the use of low-titanium alloys cannot meet the requirements of titanium content control.