摘要
对22SiMn2TiB钢连铸坯横向断裂原因进行分析。结果表明:铸坯柱状晶发达,晶间存在大量中间裂纹,且Ti、Mn元素偏聚于奥氏体晶界,使奥氏体晶界弱化。在矫直力、热应力作用下,中间裂纹沿奥氏体晶界扩展,导致连铸坯发生横向断裂。适当降低二次冷却比水量和中包过热度可获得良好的铸坯质量,有效解决22SiMn2TiB钢铸坯断裂问题。
Origins of transverse fracture of 22SiMn2TiB continuous casting slab are ana- lyzed in this paper. The results show that the columnar crystals are well developed and a large number of inter-granular cracks exist in between the crystals and further more Ti and Mn containing inclusions segregate along the austenite grain boundaries leading to the weakening of the austenite grain boundaries. Under the joint effects of the straighte- ning force and thermal stress the inter-granular cracks expand along the austenite grain boundaries, thus causing occurrence of transverse fracture of the CC slab. By reducing the secondary cooling water rate and lowering the over-heat of the tundish the problem of 22SiMn2TiB continuous casting slab fracture can be effectively solved and thus the good quality CC slab obtained as well.
出处
《武钢技术》
CAS
2012年第4期23-25,共3页
Wisco Technology
关键词
连铸坯
横向断裂
二次冷却
中间裂纹
continuously cast slab
transverse fracture
secondary cooling
center crack
