薄规格锰钛微合金化冷轧高强IF钢的试验  

Experimental study on thin gauge Mn-Ti microalloying cold-rolled high strength IF steel

作　　者：魏宝民 闫秉昊 白振华 WEI Baomin;YAN Binghao;BAI Zhenhua(Meisteel Technology Center,Academia Sinica,Baosteel,Nanjing 210039,Jiangsu,China;National Engineering Research Center for Equipment and Technology of Cold Strip Rolling,Qinhuangdao 066004,Hebei,China;State Key Laboratory of Metastable Materials Science and Technology,Yanshan University,Qinhuangdao 066004,Hebei,China)

机构地区：[1]宝钢股份中央研究院梅钢技术中心,江苏南京210039 [2]燕山大学国家冷轧板带装备及工艺工程技术研究中心,河北秦皇岛066004 [3]燕山大学亚稳材料制备技术与科学国家重点实验室,河北秦皇岛066004

出　　处：《四川冶金》2024年第6期56-60,共5页Sichuan Metallurgy

摘　　要：针对薄规格冷轧高强IF钢,冷轧轧制负荷大,轧制难度高的问题,开展了锰钛微合金化的高强IF钢设计,通过添加锰元素,发挥其强化和降低奥氏体向铁素体转变温度Ar3的作用,使得热轧能够在较低的温度下仍然在奥氏体区轧制,避免了由于轧制厚度薄,温降快,造成热轧精轧阶段在两相区完成,发生质量问题。本试验设计了高锰和常规高磷两种成分进行对比,开展了热轧-冷轧-退火-平整工序试验,通过JMatPro计算、高温膨胀仪测量体积变化,以及DSC测量热量变化三种方法分析Ar3温度,以此为依据设定热轧终轧温度,保证其在奥氏体区完成热轧轧制过程。结果表明,本试验增加0.64%Mn高锰设计和常规高磷设计相比,Ar3温度降低至少48℃,热轧终轧温度在860℃时,仍处在奥氏体区轧制,热轧可用奥氏体轧制方式轧制2.2 mm厚度的高强IF钢。同时采用高Mn设计的高强IF钢,降低了冷轧轧制力,提高了冷轧轧制速度,降低了冷轧轧制难度,退火后成品的力学性能相当,这个设计思路为轧制更薄规格的高强IF钢提供了可能。Aiming at the problems of heavy rolling load and high rolling difficulty in thin cold-rolled high-strength IF steel,the design of Mn-Ti micro-alloying high-strength IF steel was developed.By adding manganese element,the effect of strengthening and reducing Ar3 of the austenite to ferrite transition temperature was played,so that the hot rolled steel could still be rolled in the austenite zone at a lower temperature,avoiding the rapid temperature drop due to thin rolling thickness.As a result,the finishing stage of hot rolling is completed in the two-phase zone,resulting in quality problems.In this experiment,two components of high manganese and conventional high phosphorus were designed to compare,and a hot-rolling,cold-rolling,anneal-flattening process test was carried out.The Ar3 temperature was analyzed by JMatPro calculation,high-temperature dilatometers to measure volume changes,and DSC to measure heat changes.Based on this,the hot rolling final rolling temperature was set to ensure the completion of the hot rolling process in the austenite zone.The results show that compared with the conventional high-phosphorus design,the Ar3 temperature is reduced by at least 48℃,and the austenite zone is still rolling when the hot rolling final rolling temperature is 860℃.The austenite rolling method can be used to roll 2.2 mm thick high-strength IF steel in hot rolling.At the same time,the use of high-Mn design of high-strength IF steel reduces the cold rolling force,improves the cold rolling speed,reduces the difficulty of cold rolling,and the mechanical properties of the finished products after annealing are similar.This design idea provides a possibility for rolling thinner high-strength IF steel.

关 键 词：高强IF钢 薄规格 高锰 奥氏体 

分 类 号：TG3[金属学及工艺—金属压力加工]