滤清器用钢DC04-LQQ深冲件表面缺陷分析和工艺控制  

Analysis on Surface Defects of Deep-Drawing Piece of Steel DC04-LQQ for Filter and Process Control

作　　者：高菊 闫绍维 丁志军 Gao Ju Yan Shaowei Ding Zhijun(School of Qian, North China University of Science and Technology, Qian 064400 Hebei Tangyin Iron and steel Co Ltd, Tangshan 063000 Shijiazhuang Steel Co, Hebei Iron and Steel Group, Shijiazhuang 050031)

机构地区：[1]华北理工大学迁安学院,迁安064400 [2]河北唐银钢铁有限公司,唐山063000 [3]河北钢铁石钢公司,石家庄050031

出　　处：《特殊钢》2017年第4期27-31,共5页Special Steel

基　　金：河北省自然科学基金-钢铁联合研究基金资助项目(No.E2014209144)

摘　　要：DC04-LQQ钢(/%:≤0.003 5C,≤0.02Si,0.08~0.20Mn,≤0.015P,≤0.012S,0.02~0.06Als,0.06~0.08Ti,≤0.004 0N)1.2 mm冷轧板的工艺流程为铁水预处理-250 t BOF-RH-板坯连铸-热轧-冷轧-820~840℃退火。对DC04-LQQ钢滤清器深冲件表面缺陷进行了分析,结果表明,主要表面缺陷为舌状和针孔状缺陷,舌状表面缺陷部位含有O、Al、Mg和Fe等元素,其主要是钢水中Al_2O_3和MgO夹杂所致。针孔状表面缺陷部位含有K、Na、Ca、Al和Ti元素,其主要是结晶器液面波动大造成保护渣卷入所致。通过增加钢水静置时间从20 min至30 min、延长RH精炼Al脱氧和合金化之间的时间间隔由1~2 min至4 min、优化中间包吹氩制度和改造中间包包盖氩气管路、中间包氩气直径由原20 mm增至34 mm等措施,滤清器用钢表面缺陷率由原7.78%降低至2.62%,取得了显著效果。The process flowsheet of 1.2 mm cold-rolled sheet of steel DC04-LQQ （/% ： ≤ 0. 003 5 C, ≤ 0. 02Si, 0.08 - 0. 20Mn, ≤0. 015P, ≤ 0. 012S, 0.02 - 0.06Als, 0. 06 - 0. 08Ti, ≤ 0. 004 0N） is hot metal pretreatment-250 t BOF-RH-slab casting-hot-rolling- cold-rolling- annealing at 820 -840 ℃. The analysis on surface defects of deep-drawing piece of steel DC04-LQQ for filter has been carried out; the results show that the main surface defects are tongue-shaped and pinhole-shaped defects, the tongue-shaped surface defects containing O, A1, Mg and Fe etc elements are formed by A1203 and MgO inclusions in liquid and the pinhole-shaped surface defects containing K, Na, Ca, A1 and Ti etc elements are formed by entrapped mold powder in condition of large fluctuation of mold liquid surface. With the measures including increasing holding time of liquid from original 20 min to 30 rain, extending the interval between adding A1 deoxidizing and adding alloys from 1 - 2 rain to 4 min in RH refining, optimizing tundish argon blowing scheme and revamping the tundish cover argon pipeline, and increasing the tundish argon pipe diameter from original 20 mm to 34 mm, the occurring rate of surface defects of steel for filter decreases from original 7. 78% to 2. 62% to get obvious effect.

关 键 词：冷轧深冲钢DC04-LQQ 夹杂物 表面缺陷 工艺改进 

分 类 号：TF76[冶金工程—钢铁冶金] TG335.5[金属学及工艺—金属压力加工]