分析结果表明，铸锭中分布不均匀的非金属夹杂物和组织中过量分布于晶界的贝氏体和三次渗碳体是导致冷镦开裂的原因。
It was revealed that : inhomogeneous distribution of the non-metallic inclusion and excessive bainite and tertiary cementite is the cause of cracking .
三次渗碳体