摘要
为减少超低碳冷轧汽车板表面质量缺陷，对直弧形连铸机生产的超低碳连铸坯沿厚度方向不同深度截取70mm×80mm大尺寸金相试样，采用ASPEX explorer自动扫描电镜对大尺寸夹杂物分布特征进行了研究，得到夹杂物的成分、数量、尺寸与分布特征。结果表明，在铸坯w（T．O）降至0．0012％时依然存在较多大型夹杂物，绝大多数为簇群状Al2O3，部分伴生有钢液凝固时析出生成的TiN；其余为少数“气泡＋Al2O3”夹杂物，其尺寸均在30～100μm，少数在100μm以上，这些夹杂物在铸坯厚度1／4处呈现更明显的聚集。
To decrease the surface defects on cold rolling sheets caused by inclusions, large inclusions in ultra-low carbon steel slab produced by bending vertical caster were characterized in details along the whole thickness direction. Metallographic samples with large section dimension of 70 mm×80 mm were specially prepared, and the inclusions were inspected by the automatic secondary electron microscopy ASPEX explorer. It was found many large inclusions still exist even T. O mass fraction in slab was reduced to 0.001 2 %. Most majority of them were alumina clusters within 20 - 200μm and the others were the ＂bubble ＋ Al2O3＂ type with big sizes in the range of 30 - 100 μm and some were larger than 100 μm. While the well-known mold-flux entrapped inclusions were not detected. These large inclusions were not only in the surface/subsurface but also located deeply in the slab, indicating an obvious quarter-band accumulation especially for the ＂bubble ＋ Al2O3＂ inclusions.
出处
《炼钢》
CAS
北大核心
2016年第2期60-63,68,共5页
Steelmaking
关键词
超低碳钢
夹杂物
三氧化二铝
气泡
连铸坯
ultra-low carbon steel
inclusion
alumina
bubble
continuous casting slab
