贝氏体非调质钢FAS2225轧坯孔洞缺陷分析及工艺改进

特殊钢

贝氏体非调质钢FAS2225轧坯孔洞缺陷分析及工艺改进

阎岩，郝彦英，刘献达

(河钢集团石家庄钢铁有限责任公司技术中心,石家庄050031)

An Analysis and Process Improvement on Hole-Defect of Hot-Rolled Billet of Non-Quenched and Tempered Bainite Steel FAS2225

Yan Yan, Hao Yanying and Liu Xianda

(Technology Center, Shijiazhuang Iron and Steel Co, HBIS Group, Shijiazhuang 050031)

摘要/Abstract

摘要： FAS2225 钢(/% ：0.26C, 0.35Si, 1. 99Mn, 0.013P, 0.046S, 0.54Cr, 0.12V, 0.02Mo, 0.08Ni, 0.0012O, 0.0070N)的生产流程为铁水预处理-60 t顶底复吹转炉-LF-VD-300 mm x 360 mm坯连铸-连轧。在215 mm x 213 mm轧坯上出现中心开裂形成孔洞。经分析得出，加热速度过快及温度梯度过大产生的热应力和组织应力使连铸坯发生开裂造成轧制过程孔洞缺陷。通过预热段加热温度从900 °C降至750°C，延长加热时间、温度梯度从Δ200°C降至Δ100 °C ,有效遏制了孔洞缺陷的产生。

关键词: 贝氏体型非调质钢, FAS2225, 铸坯加热, 中心开裂, 热应力, 组织应力, 预热温度

Abstract: The production flowsheet of steel FAS2225 (/% : 0. 26C, 0. 35Si, 1.99Mn, 0. 013P, 0. 046S, 0. 54Cr, 0. 12V, 0. 02Mo, 0. 08Ni, 0.0012O, 0.0070N) is pretreated hot-metal-60 t top and bottom combined brown converter- LF-VD-300 mm x 360 mm bloom casting-continuous rolling. The hole formed by center crack of 215 mm x 213 mm rolled billet occurs. And it is obtained by analysis that the thermal stress and structure stress produced by larger heating speed and temperature gradient of casting bloom lead to cracks of bloom and forming hole-cracks of billet during rolling process. By decreasing the heating temperature of bloom at preheating zone in heating furnace from 900 °C to 750 °C , prolonging heating time and decreasing temperature gradient from Δ200 °C to Δl00 °C , it is available to inhibit the formation of hole-defects.

阎岩, 郝彦英, 刘献达. 贝氏体非调质钢FAS2225轧坯孔洞缺陷分析及工艺改进[J]. 特殊钢.

Yan Yan, Hao Yanying and Liu Xianda. An Analysis and Process Improvement on Hole-Defect of Hot-Rolled Billet of Non-Quenched and Tempered Bainite Steel FAS2225[J]. Special Steel.

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[2]	董爱锋, 张文康. 取向硅钢生产工艺技术分析和发展趋势[J]. 特殊钢, 2013, 34(5): 20-24.