中厚板中心分层原因分析与预防措施

Cause Analysis and Preventive Measures of Center Lamination in Medium Steel Plate

通过光学显微镜、扫描电镜和能谱仪等手段对厚度1/2处出现分层的连铸坯成材钢板进行分析,研究钢板分层的原因及预防措施。结果表明:连铸坯出现严重的中心偏析和较多夹杂物,而轧制后应力集中在板厚中心处,在后续热处理过程中,应力集中释放,造成钢板分层。通过改进连铸设备和工艺、优化连铸二冷水等措施,使钢板的中心分层现象得到明显改善。

By means of optical microscope’scanning electron microscope and energy spectrometer, analysis is performed on the center lamination of steel plate rolled from continuous cast slab in order to study the lamination causes and their preventive measures. The results show that there existed severe central segregation and more inclusions in the continuous cast slab. After rolling,the stress concentrated at the center position of steel plate. In the process of subse-quent heat treatment,the stress was relieved,which resulted in steel plate lamination. On the basis of variouB measures taken to improve continuous casting equipment and process and optimize secondary cooling water of continuous caster, the center lamination of steel plate has been significantly reduced.