包晶钢铸坯裂纹形成机理的实验研究  

Mechanism of Crack Formation During Continuous Casting of Peritectic Steel Slabs

作　　者：高仲 张兴中 姚书芳 

机构地区：[1]中冶连铸北京冶金技术研究院,北京100081 [2]中国钢研科技集团公司,北京100081

出　　处：《钢铁研究学报》2009年第10期8-11,共4页Journal of Iron and Steel Research

基　　金：国家863计划资助项目(2005AA331020)

摘　　要：针对包晶钢在连铸生产中铸坯裂纹出现较严重,选用具有相似收缩特征的Ag-Zn合金作为研究对象,开展定向凝固实验。研究得出,包晶钢包晶相变过程中包晶转变(δ→γ)阶段引起的收缩是导致铸坯裂纹的主要原因。与过包晶钢相比,亚包晶钢因在包晶相变过程中有较多的δ铁生成量和较少富余液相的补缩,铸坯更容易出现裂纹。亚包晶钢铸坯裂纹较低碳钢严重,是因为低碳钢发生包晶转变的温度低,避开了钢的零强度和零塑性温度区。Aiming at serious cracks generated during continuous casting of periteetic steel slabs, the unidirectional solidification experiment was carried out using the Ag-Zn alloy whose shrinking properties are similar to those of Fe-C alloy during peritectic phase transformation. The results show that the cast crack is mainly caused by shrinkage during perirtectic transformation （δ→γ）. And for this reason, the subperitectic steel bears more crack on the slab than other kinds of steel. Subperitectic steel have more 3 phase and less residual liquid feeding than superperitectic steel during peritectic phase transformation, so subperitectic steel slabs are prone to generate cracks. The cracks of subperitectic steel slabs are more serious than those of low carbon steel slabs, because the perirtectic transformation temperature of low carbon steel is low enough to out of the zero ductility temperature zone as well as zero strength temperature zone of the steel.

关 键 词：包晶钢 包晶转变 裂纹 

分 类 号：TF777[冶金工程—钢铁冶金]