Smelting technique and production method of bearing steel and bearing steel

Abstract

The invention relates to a smelting technique and production method of bearing steel and the bearing steel. Impurities in the bearing steel are controlled through the smelting technique. Low-titanium ferrochromium with the Cr content being equal to or higher than 75% serves as raw materials, and Al is added at one time for deoxidation before smelting and tapping of an electric furnace. High-purity silicon carbide with the purity being larger than 95% is adopted for deoxidation. After degassing of a vacuum furnace is conducted, the standing time of molten steel is not shorter than 10 minutes. By the adoption of a tundish current regulator, a covering agent with the calcium oxide content being not smaller than 50% serving as a tundish covering agent, and casting powder with the calcium oxide content being not smaller than 34% serving as tundish casting powder, the bearing steel is obtained, wherein the A type coarse impurity content of the beating steel is smaller than or equal to 1.0%, the A type fine impurity content of the beating steel is smaller than or equal to 1.0%, the B type coarse impurity content of the beating steel is smaller than or equal to 0.5%, the B type fine impurity content of the beating steel is smaller than or equal to 0.5%, the D type coarse impurity content of the beating steel is smaller than or equal to 0.5%, the D type fine impurity content of the beating steel is smaller than or equal to 0.5%, the C type coarse impurity content of the beating steel is 0, the C type fine impurity content of the beating steel is 0, and the DS type impurity content of the bearing steel is smaller than or equal to 1.0%. By the adoption of the smelting technique, the content of all the impurities is greatly reduced.

Description

technical field [0001] The invention relates to a smelting process and a production method of bearing steel and GCr15 bearing steel, belonging to the technical field of bearing steel production and manufacturing. Background technique [0002] The quality of bearing steel mainly depends on the purity of the billet, that is, the content of non-metallic inclusions in the steel. [0003] Microscopic non-metallic inclusions that affect the purity of bearing steel are divided into ABCD and DS types, of which A type is sulfide type inclusions, B type is alumina type inclusions, C type is silicate type inclusions, and D type is spherical oxides DS type inclusions are single particle spherical inclusions. In addition, it also includes macroscopic inclusions such as tundish covering agent or mold slag involved in the casting process. [0004] Generally, the content of sulfur element in bearing steel is required to be in a lower range, and sulfides in molten steel are less generated, ...

AI Technical Summary

Problems solved by technology

[0007] Therefore, the technical problem to be solved by the present invention is to overcome the technology of bearing steel smelting process in the prior art that causes the final produced bearing steel to contain high inclusions, cracks and uneven deformation in the billet forging process, resulting in short service life of the finished product problems, and further provide a smelting process of high-purity bearing steel that can significantly improve the cracking and uneven deformation of the billet during the forging process, and improve the service life of the finished product

[0008] Another technical problem to be solved by the present invention is to overcome the high content of inclusions in the bearing steel produced by the bearing steel production method in the prior art, which leads to cracking and uneven deformation in the billet forging process, so that the service life of the finished product Short technical problems, and then provide a production method of high-purity bearing steel that can significantly improve the cracking and uneven deformation of the billet during the forging process, and improve the service life of the finished product

[0009] Another technical problem to be solved by the present invention is to overcome the technical problem that the high content of inclusions in the bearing steel in the prior art leads to cracking and uneven deformation during the forging process of the steel billet, which makes the service life of the finished product short, and further provides a A high-purity bearing steel that can significantly improve the cracking and uneven deformation of the billet during the forging process, and improve the service life of the finished product