基于铁素体轧制工艺低碳铝镇静钢板r值降低原因分析

Cause analysis of r value decreasing of low carbon aluminum-killed steel sheet developed based on ferrite rolling process

某钢厂试开发基于铁素体轧制工艺的SPCC板,经热轧-冷轧-罩式退火工序后对样品进行性能检测,发现与传统奥氏体轧制工艺相比,该工艺路径下的产品各项力学性能指标均有不同程度下降,且r值有明显降低。对两种工艺路径的热轧板和冷轧退火成品板进行了组织和织构的对比分析,且提出了改进措施。结果表明:铁素体轧制工艺中热轧精轧温度过高,形成两相区轧制,得到粗大F+纤维状F的不均匀室温组织,从而导致冷轧退火板中存在较高强度{001}<110>织构组分,是导致最终产品r值降低的主要原因。

A steel plant tried to develop an SPCC sheet based on ferritic rolling process,cold rolling and bell annealing.It was found that compared with the traditional austenite rolling process,the mechanical properties of the products under this process route were decreased in varying degrees,and the r value was significantly reduced.Then the microstructure and textures of hot rolled sheet and cold rolled annealed sheet with these two processing routes were compared and analyzed,and the improvement measures were put forward.The results show that in the ferrite rolling process,the hot rolling finishing temperature is too high to form two-phase zone rolling,resulting in the uneven room temperature microstructure of coarse F+fibrous F,so that resulting in the existence of high strength {001}<110> texture components in the cold rolled annealed sheet,which is the main reason for the reduction of r value of the final product.