Although the requirements of bearing the use of more and more high, but also requests its service life is longer than before. However, because the ball bearing occasional spalling, thus prolonging the service life of bearing is very difficult. In order to meet user requirements more stringent, must through the reduction of oxide and nitride inclusions in steel to improve the cleanness of steel.

对于更洁净的钢来说，采用传统的ASTM方法分析疲劳寿命与钢的洁净性关系非常困难，因此就需要新的夹杂物测定方法。本文将介绍日本神户制钢公司开发的用于轴承的超洁净钢生产技术和新的夹杂物测定技术。

For more clean steel, by traditional ASTM method for analysis of relationship between fatigue life and steel cleanliness is very difficult, so it needs a new method for the determination of inclusions. This paper will introduce the development of Japanese Kobe Steel Company for the determination of bearing production technology of super clean steel and inclusions.

一、轴承用超洁净钢生产技术

The production technology for a super clean steel, bearing

1、超洁净钢的生产

1, the super clean steel production

神户制钢在神户钢厂和加古川厂冶炼、连铸了用于轴承的高碳铬钢。这种钢除了采用更严格的精练工艺以使氧化物和氮化物夹杂最小化外，其生产工艺与普通钢相同。

Kobe Steel in Kobe Steel and kakogawa works smelting, casting the high carbon chromium steel used for bearings. This kind of steel in addition to the scouring process more stringent in order to make the oxide and nitride inclusions minimization, its production process and the same as ordinary steel.

经铁水预处理充分脱磷和脱硫的铁水在转炉中进行脱碳处理。转炉渣是一种氧化渣。为了减少氧化物夹杂，炉渣被切断，因而使氧化物夹杂不会流入钢包中。在精炼（加热、脱气）和连铸时，钢水被比平常更严的惰性气体屏蔽以防止与空气接触发生二次氧化。在精炼过程中，由于渣的碱度非常高，钢水经充分搅拌，使氧化物夹杂（主要是三氧化二铝）上浮进入渣中，因此，钢变得更洁净，只有很少量的夹杂。在连铸时，神户厂利用中间罐加热器加速钢水中的夹杂上升，加古川厂是采用较大的中间罐。

The pretreatment of hot metal dephosphorization and desulfurization of hot metal in the converter in the decarburization process. Converter slag is a kind of oxide slag. In order to reduce the oxide inclusion, slag is cut off, so that the oxide inclusions can not flow into the steel in ladle. In the refining (heating, degassing) and continuous casting, molten steel by inert gas shielding than usual more strict in order to prevent contact with air oxidation occurred two times. In the refining process, due to the basicity of the slag is very high, the steel stirring, the oxide inclusions (mainly three two aluminum oxide) floating in the slag steel, therefore, become more clean, only a very small amount of inclusions. In the continuous casting tundish heater, Kobe plant using accelerated in molten steel inclusion rise, kakogawa works is the use of tundish greatly.