摘要
在工业试验的基础上,对高碳钢大方坯实施轻压下后铸坯中心区域产生严重的负偏析与微弱的正偏析的形成机制进行了探讨与分析,研究发现:铸坯实施轻压下后,优先生长的上下两层的树枝晶会在外力的作用下发生碰撞、折断破碎,折断破碎的细小晶粒在钢液的强迫流动作用下随机漂流到铸坯中心区域成为新的晶核,从而使其周围钢液先凝固,形成负偏析;此后富集元素钢液凝固形成微弱的正偏析。
Based on industrial testing,the mechanism of negative segregation and slight positive segregation forming in the central region of high carbon steel bloom with soft reduction was discussed.It is found that up and down two layers of the dendrites preferentially growing collide each other under some extra force and are broken after the implementation of soft reduction.Some small broken crystals may randomly drift into the central region of the bloom by the effect of liquid steel and become the new crystal nucleus,which make the surrounding liquid steel solidify firstly and lead to negative segregation.After the formation of negative segregation,slight positive segregation is formed because of the solidification of liquid steel enriched in elements.
出处
《钢铁》
CAS
CSCD
北大核心
2010年第8期44-46,60,共4页
Iron and Steel
关键词
大方坯
帘线钢
偏析
轻压下
bloom
tire cord steel
segregation
soft reduction
