303Cu大规格线材低温轧制头部开裂原因分析及改进措施

针对永兴特种不锈钢股份有限公司303Cu易切削钢φ14 mm大规格线材减定径轧制过程中出现线材头部开裂问题，对其产生原因进行了分析。结果表明，303Cu易切削钢因S含量较高，易形成MnS夹杂，而MnS夹杂的变形能力与钢基体相差较大，在轧制温度较低且轧制力较大的情况下，线材头部容易开裂。为此，对孔型系统进行了改进，减小减径机中的轧制力，使MnS夹杂受到的剪切应力较小，降低了使其脱离基体的可能性，解决了φ14 mm大规格线材头部开裂的问题。

Cause analysis of head cracking of 303Cu steel large gauge wire rod at low temperature rolling and its countermeasures

Aiming at the problem of head cracking during reducing and sizing rolling of 303Cu free-cutting steel of φ14 mm large gauge wire production in Yongxing Special Stainless Steel Co.,Ltd.,the cause was analyzed.The results show that 303Cu free-cutting steel is easy to form MnS inclusions due to the high S content,and the deformation capacity of MnS inclusions is greatly different from that of the steel matrix.When the rolling temperature is lower and the rolling force is large,the wire head is easy to crack.Therefore,the pass system was improved,the rolling force in the reducing mill was reduced,the shear stress on the MnS inclusion was reduced,and the possibility of leaving the basement metal was reduced.The head cracking problem of φ14 mm gauge wire was solved.