H型钢Q235B连铸保护渣的优化  

Optimization of Mold Powder for H-Shape Steel Q235B Casting

作　　者：尹娜[1] 景财良[1] 张炯明[1] 韩毅华[1] 王伟[1] 

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083

出　　处：《特殊钢》2010年第2期40-42,共3页Special Steel

基　　金：国家自然科学基金与宝钢联合资助项目(50774109)

摘　　要：针对津西钢铁厂H型钢Q235B(0.14%～0.18%C)铸坯(宽面550 mm,窄面440 mm,腹板90 mm)经常出现纵裂等缺陷,基于原有保护渣(%:29～30SiO_2、25～26CaO、10～11Al_2O_3、3.0～3.5Fe_2O_3、15～17C、≤0.5H_2O),通过正交实验和优化设计,开发出一种高性能保护渣(%:37.50SiO_2、37.50CaO、6Al_2O_3、7CaF_2、12Na_2O、7石墨、1.5炭黑)。与原保护渣相比,优化渣的半球点温度、粘度和熔化时间分别从1 167℃,0.77 Pa·s和57 s下降至1 092℃,0.27 Pa·s和32.5 s。优化渣应用表明,当拉速由0.98 m/min提高到1.2 m/min时,铸坯质量良好。To counter the situation of longitudinal crack defect usually occurred on bloom （ wide side 550 mm, narrow side 440 mm, waist 90 mm） in H-shape steel Q235B （0. 14% - 0. 18% C） casting at Jinxi Iron and Steel works, based on original mold powder （%：29～30SiO2,25-26CAO,10-11Al2O3,3.0-3.5Fe2O3,15～17C,≤0.5H20） , a high performance mold powder （%：37.50SiO2,37.50CaO,6Al2O3,7CaF2,12Na2O,7 graphite, 1.5 carbon black） is developed by orthogonal experimental and optimum design. As compared with original mold powder, the semi-sphere point temperature, viscosity and melting time of improved mold powder decrease respectively to 1 092 ℃, 0. 27 Pa · s and 32. 5 s from original 1 167 ℃, 0.77 Pa · s and 57 s. Application shows that as casting speed increase from 0.98 m/min to 1.2 m/min, the bloom has high quality by using the improved mold powder.

关 键 词：H型钢Q235B 连铸 正交试验 保护渣优化 

分 类 号：TF777[冶金工程—钢铁冶金] TG335.42[金属学及工艺—金属压力加工]