优化冷却工艺降低轴承钢网状

Optimization of the Cooling Process to Reduce Carbide Tissue in Bearing Steel

提高轴承钢质量关键是提高轴承钢疲劳寿命,轴承钢提高疲劳寿命方法之一就是提高钢材的组织均匀性,降低轴承钢棒材网状是提高组织均匀性关键之一。某钢厂采用235 mm×265 mm连铸坯,通过800连轧机组轧制,采用PCS冷却系统冷却,对GCr15轴承钢Ф50进行水冷试验。通过试验表明,轴承钢棒材轧后不进行水冷网状组织级别较高,单段水冷系统冷却由于最后由心部返温,降低网状效果不明显,采用两段次需要充分考虑水冷段距离,距离较远有充足的返温时间,然后再进行冷却,能够有效降低网状组织。三段水冷全部投入使用能够有效降低网状,最终轴承钢的网状级别可控制在2.5级以内。

The key to improve the quality of bearing steel is to increase the fatigue life. One of the methods to increase the fatigue life is to improve the uniformity of structure, decrease of the level of carbide tissue of bearing steel is very important. Billet with size of 235×265mm was selected and rolled by the 800 rolling mills ,then cooled with the PCS cooling system, finally the GCr 150 bearing steel with diameter of 50mm was under water-cooling test. The test results showed that the carbide tissue grade is high for the bearing steel without water cooling, and the carbide tissue deduction was not One steel adopt the size of billet is not obvious for the single cooling process due to the temperature recovery from the center, while the carbide tissue network reduction was effective for the dual-phase cooling process due to the sufficient temperature recovery period acquired by the long cooling distance. The carbide tissue deduction was effective for the triple cooling phase, with carbide tissue network grade of less than 2.5.