Production of clean high carbon chromic bearing steel

Abstract

A method for manufacturing high-cleaning and high carbon complex bearing steel includes: 1) choosing charging mixture 2) first steel making molten steel by is greater than or equal to 30ton electric furnace a. smelting furnace burden b. running out foaming slag and adding lime c. alloying when steel tapping with 92% tap and >90% level 3) refining molten steel by steel ladle furnace a. cleaning steel ladle and furnace cleaning b. through bottom blowing argon mixing with 60 min, earlier stage argon blowing intensity 0.4Mpa and later stage 0.3Mpa, material adding amount is less than or equal to 8Kg/ton steel c. precipitating and deoxidizing by two-stage aluminum feeding method, adding crystallized silicon powder, fluorite(content of calcium is greater than or equal to 98%) into slag face, and dispersing deoxidizing 4) vacuum furnace treating a. bottom blowing argon 0.3Mpa, 25min, vacuum content is less than or equal to 140Pa b. bottom blowing argon mixing 15min, 0.1Mpa without materials after treating 5) molten steel mould casting under inactive gas a. ingot moulding temperature 70deg.C, runner brick coating b. pouring speed 5.1ton steel/min of ingot body and mouth. It achieves high yield.

Description

technical field [0001] The invention relates to a production method of bearing steel in the metallurgical industry, in particular to a smelting production method of high-carbon chromium bearing steel. Background technique [0002] The cleanliness of the century-old high-carbon chromium bearing steel is closely related to the fatigue life of the bearing (the fatigue life of the bearing is generally determined by the shape, size, quantity and uniformity of the inclusions in the steel.). For a long time (before the 1990s), metallurgists have always regarded the oxygen content as a key indicator to measure the life of the bearing (in the 1980s, the main indicator of cleanliness was the oxygen content in the steel: the lower the oxygen content, the higher the fatigue life of the bearing) , and a lot of research and practical work have been done on reducing the oxygen content. The oxygen content (oxygen activity + oxide inclusions) of high-carbon chromium bearing steel in Japan, S...

AI Technical Summary

Problems solved by technology

[0004] At present, the bearing steel manufacturers that can meet the basic requirements of precision bearing manufacturers for the high cleanliness and purity of high-carbon chromium bearing steel mainly include Japan abroad. Method ("World Metal Bulletin", February 25th, 2003, 3rd edition); Datong Zhiduo Steel Works developed a production method with oxygen content≤5ppm, Ti<≤6ppm according to the EAF-LF-RH-CC process flow (Japan " Electric Steel "Volume 73 No. 1, January 2002, P61), but there is no introduction to detailed technology; and domestic literature reports are only Baosteel Group Shanghai No. Steel smelting production method (Patent No.: ZL01132236.5), which is characterized by the development of a high-carbon chromium bearing steel production method with an oxygen content of ≤7ppm and a titanium content of ≤12ppm according to the DC-LF-VD-IC process flow, ZL01132236. The disadvantages of the 5 invention patent are: although the requirement that the ladle must be cleaned is put forward, the "completely manual cleaning" implemented in the actual operation process is labor-intensive and the cleaning effect is not ideal; secondly, the process of adding materials after vacuuming The chemical balance of steel slag is dest...