赵景存, 朱叶. Cause Analysis on Surface Crack of Drill Steel 55SiMnMo Rolling Product and Process Improvement[J]. Special Steel, 2023, 44(1): 45-48. DOI: 10.20057/j.1003-8620.2022-00100.
针对100 t BOF-LF-VD-Φ450 mm连铸坯-Φ200 mm轧材流程生产的钎具钢55SiMnMo轧材表面易产生裂纹缺陷,分析对比了过热度、二次冷却、拉速、成分(Ti.B)等对缺陷的影响。通过工艺改进;控制钢水过热度20~30℃
控制B含量≤0.0008%
加Ti 0.015%~0.025%
拉速0.41 m/min
二冷比水量0.17 L/kg
使裂纹的缺陷率由原来的12.2%降低到1.6%。
Abstract
The surface of rolled products of drill steel 55SiMnMo produced by 100 t BOF-LF-VD-4450 mm CC bloom- φ200 mm rolling bar production process is prone to surface crack.The effect of superheat
secondary cooling
casting speed and composition(Ti.B)on defects are analyzed and compared. Through process improvement which is obtained that by controlling superheat 20-30 ℃
B content controlled≤0.0008%
Ti content 0.015%-0.025%
drawing speed 0.41 m/min
and secondary cooling ratio 0.17 L/kg
the crack defect rate decreases from 12.2% to1.6%.