通过对莱钢H型钢腹板裂纹组织的金相和扫描电镜分析发现,在裂纹周围组织中存在大量异质颗粒。为了弄清此类异质颗粒的性质及其与裂纹之间的联系,以及具有该相同特征的裂纹组织的形成过程,特设计预制裂纹实验方案进行验证,通过试验研究,发现了异质颗粒的性质及其与裂纹之间的联系,分析出具有该相同特征的裂纹组织的形成过程,总结出了影响异质颗粒形成及大小的主要因素。分别从连铸、加热和轧制3个工序制定了预防措施以减轻或消除腹板裂纹。 Through the metallographic and scanning electron microscopy analysis of the cracked webs of the H-section steel in Laiwu Steel, a large number of heterogeneous particles exist in the tissues around the crack. In order to clarify the nature of such heterogeneous particles and the relationship between them and cracks, and the formation process of cracked structures with the same features, a prefabricated crack experimental scheme was designed to verify the experimental study and found that heterogeneous particles Nature and its relationship with the crack, analyze the formation process of the cracked structure with the same features, summed up the main factors that affect the formation and size of heterogeneous particles. From the three steps of continuous casting, heating and rolling, preventive measures have been formulated to reduce or eliminate web cracks.