铁素体轧制Ti-IF钢冲压成形条纹缺陷原因分析与改进措施  

Cause analysis of stripe defect generated on ferrite rolled Ti-IF steel strip after stamping and its countermeasures

作　　者：王晓东 高文刚[2] 谭志福[2] WANG Xiaodong;GAO Wengang;TAN Zhifu(Technical Center,Shougang Jingtang United Iron and Steel Co.,Ltd.,Tangshan 063200,China;Hot Rolling Department,Shougang Jingtang United Iron and Steel Co.,Ltd.,Tangshan 063200,China)

机构地区：[1]首钢京唐钢铁联合有限责任公司技术中心,河北唐山063200 [2]首钢京唐钢铁联合有限责任公司热轧部,河北唐山063200

出　　处：《轧钢》2021年第4期38-43,共6页Steel Rolling

基　　金：2017年北京市国资委资助项目(京唐铁素体区轧制技术创新团队)。

摘　　要：针对铁素体轧制工艺生产的Ti-IF带钢冲压后出现条纹缺陷的问题,通过对其力学性能与微观组织分析,并与未出现缺陷的正常批次带钢进行比较,表明冷轧退火后带钢屈服强度偏低、晶粒尺寸与Δr值偏大是导致冲压出现条纹缺陷的主要原因。对生产工艺进行了研究,发现热轧工艺中板坯加热温度、终轧温度与卷取温度偏低,且冷轧退火温度偏高,是导致冷轧退火带钢性能偏低的原因。为此,提出了工艺优化措施:将板坯加热温度由原来的1100℃提高到1130℃,将目标终轧温度按照810℃控制,将冷轧后退火温度由800℃降低到780℃,并将退火缓冷段与快冷段温度分别下调20℃与50℃。工艺优化后提高了带钢屈服强度,减小了Δr值,解决了铁素体轧制Ti-IF钢冲压后出现条纹缺陷的问题。In view of the stripe defects appeared on the surface of Ti-IF steel strip after stamping which was produced by ferrite rolling process,its mechanical properties and microstructure were analyzed,and comparisons with those of the production lots without that defect were carried out.The results show that the main root causes of the stripe defect after stamping are that the cold rolled and annealed strip has lower yield strength,larger size of grain and largerΔr value.After the studying on producing processes,it shows that the reasons for lower mechanical properties of cold rolled and annealed strip are the lower reheating temperature of slab,lower finishing rolling and coiling temperatures and higher annealing temperature.Therefore,processing optimization measures were put forward.The temperature of slab reheating was increased to 1130℃from 1100℃,aiming value of finishing rolling temperature was controlled to be 810℃,the annealing temperature after cold rolling was decreased to 780℃from 800℃,and the temperatures of slow and fast cooling segments were decreased by 20℃and 30℃respectively during the annealing.After the optimized processes were carried out,the yield strength of strip was increased,Δr value was decreased,and the defect problem was solved.

关 键 词：铁素体轧制 TI-IF钢 冲压成形 条纹缺陷 力学性能 金相组织 加热温度 终轧温度 退火温度 

分 类 号：TG335[金属学及工艺—金属压力加工] TG386