摘要
分析了在吊运过程部分25SiMn2钢重22t170mm×1650mm×10000mm连铸板坯断裂的原因。结果表明,浇铸时中间包钢水过热度高(30—36℃),引起铸坯厚度1/4位置柱状晶发达,钢液凝固时流动性不好,补缩不足,出现大量显微缩孔,并在反复吊运后在自身重力作用下,显微缩孔处应力集中开裂而造成铸坯断裂。通过降低中间包钢水过热度(10—30℃)、减少吊运次数可有效避免铸坯断裂。
The cause for fracture of partial 22 t 170 mm × 1 650 mm× 10 000 mm casting slab of steel 25SiMn2 dur- ing crane-conveying process has been examined and analyzed. Results show that during casting the superheating extent of liquid steel in tundish is higher (30 ~ 36 ℃ ) led to significant columnar crystal growth at 1/4 thickness of slab, poor fluid- ity of molten steel and lack back feeding during solidification, as result a lot of micro-shrinkage cavity occur causing crack at micro-shrinkage cavity by stress concentration effect and finally causing fracture of slab by repeating crane-conveying and acting with self-gravity. The fracture of casting slab is availably avoided by decreasing superheating extent of liquid in tundish to 10 - 30 % and reducing times of crane-conveying of slab.
出处
《特殊钢》
北大核心
2014年第4期34-36,共3页
Special Steel
关键词
25SiMn2钢
吊运铸坯断裂
柱状晶
中间包钢水
过热度
Steel 25SiMn2, Crane-Conveying Slab Fracture, Columnar Crystal, Liquid in Tundish, Superheating Extent