一、前言 普炭钢中有一定量的Cu、As、Sb、Sn残余元素时,在热加工过程中,常引起钢的热脆,它多产生于轧制头几道次和不均匀变形严重道次。龟裂在刚产生初期,只是横向裂纹,继继轧制,随轧件的延伸及金属的流动,裂纹变宽。金相检验及夹杂物分析表明,尽管龟裂严重,钢的组织却是正常,并无过烧现象,龟裂与夹杂物亦无对应关系,生产和试验分析表明:钢材上的这种缺陷,主要是钢中Cu、As、Sb、Sn元素含量较高并在高温下选择性氧化而引起表面富 I. Introduction Pre-carbon steel in a certain amount of Cu, As, Sb, Sn residual elements, in the thermal processing, often caused by the hot brittle steel, it is mostly produced in the rolling head several times and uneven deformation of severe Road Times. Cracks in the early days, just horizontal cracks, followed by rolling, with the extension of the rolling and metal flow, the crack broadens. Metallographic examination and analysis of inclusions showed that although the cracks were severe, the microstructure of the steel was normal and there was no over-burning phenomenon. There was no corresponding relationship between the cracks and inclusions. Production and test analysis showed that the defects on the steel, Mainly in steel Cu, As, Sb, Sn elemental content is high and selective oxidation at high temperature caused by surface rich