摘要
采用热态试验对半钢冶炼Ti-IF钢的非金属夹杂物进行研究,并就提高钢水洁净度和降低夹杂物尺寸进行工艺优化。研究表明:LF进站时夹杂物为球状FeO-MnO,LF出站时主要夹杂物为包裹状、簇状MgO-FeO-MnO-Al_(2)O_(3),RH脱碳结束后主要为球状、纺锤体状和不规则状FeO-Al_(2)O_(3),RH铝脱氧3 min后主要为三角状、类球形和团簇状Al_(2)O_(3),Ti合金化3 min后主要为六边形状TiO_(2)-Al_(2)O_(3)、纺锤体状和近似菱状Al_(2)O_(3),RH出站为球形TiO_(2)-Al_(2)O_(3)、纺锤体状和近似菱状Al_(2)O_(3)夹杂物,铸坯中主要为菱形TiN、类球形Al_(2)O_(3)和不规则形Al_(2)O_(3)-TiN。原工艺影响Ti-IF钢表面质量和钢液纯净度的非金属夹杂物主要是大尺寸Al_(2)O_(3)(大于等于15μm)。通过优化氧枪喷头、RH工艺参数和中间包流场,铸坯中w(T.O)降至16.3×10^(-6),最大非金属夹杂物尺寸降至9.5μm, Ti-IF钢水洁净度得到显著提高。
The non-metallic inclusions in Ti-IF steel smelted by semi-steel was studied by thermal test to improve the cleanliness of molten steel and reduce the size of inclusions for process optimization. The research shows that the inclusions are spherical FeO-MnO in LF inlet, the main inclusions are wrapped and clustered MgO-FeO-MnO-Al_(2)O_(3) in LF outlet. The main inclusions are mainly spherical, spindle-shaped and irregular FeO-Al_(2)O_(3) after RH decarburization, and are mainly triangular, quasi-spherical and clustered Al_(2)O_(3) after RH aluminum deoxidation for 3 minutes. After Ti alloying for 3 minutes, the main shapes of inclusions are hexagonal TiO_(2)-Al_(2)O_(3), spindle-shaped and almost diamond-shaped Al_(2)O_(3). After leaving the RH station, the inclusions are spherical TiO_(2)-Al_(2)O_(3), spindle-shaped and nearly diamond-shaped Al_(2)O_(3) inclusions. The inclusions in the slab are mainly diamond-shaped TiN, quasi-spherical Al_(2)O_(3) and irregular-shaped Al_(2)O_(3)-TiN. The non-metallic inclusions in the original process that affect the surface quality of Ti-IF steel and the purity of molten steel are mainly large-sized Al_(2)O_(3)(≥15 μm). By optimizing the oxygen lance nozzle, RH process parameters and tundish flow field, the T.O mass fraction in slab is reduced to 16.3×10^(-6), the maximum non-metallic inclusion size is reduced to 9.5 μm. So the cleanliness of Ti-IF molten steel is significantly improved.
作者
耿立唐
张明博
王宝华
王世钊
宫永煜
GENG Litang;ZHANG Mingbo;WANG Baohua;WANG Shizhao;GONG Yongyu(Chengde Branch of HBIS Company Limited,Chengde 067102,China)
出处
《炼钢》
CAS
北大核心
2021年第4期49-57,共9页
Steelmaking
