基于热轧全流程氧化铁皮控制的耐蚀性工艺  

Corrosion resistance process based on control of oxide scale in whole process of hot rolling

作　　者：李成刚[1] 单文超 刘怡私 杨名 王皓 曹光明[1] LI Cheng-gang;SHAN Wen-chao;LIU Yi-si;YANG Ming;WANG Hao;CAO Guang-ming(The State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,Liaoning,China;Technology Center,Hunan Valin Lianyuan Iron and Steel Co.,Ltd.,Loudi 417000,Hunan,China)

机构地区：[1]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110819 [2]湖南华菱涟源钢铁有限公司技术中心,湖南娄底417000

出　　处：《钢铁》2021年第9期129-135,共7页Iron and Steel

基　　金：国家重点研发计划资助项目(2017YFB0304104);国家自然科学基金资助项目(U1660117);中央高校基本科研业务费资助项目(N180704008)。

摘　　要：针对热轧生产流程实际工况,系统研究了热轧、卷取阶段的三次氧化铁皮演变规律,旨在不增加生产成本的前提下,通过调整热轧生产工艺控制氧化铁皮结构,利用热轧后生成的氧化铁皮作为防护屏障,提高钢材耐蚀性能。结果表明,在不同轧制温度下,三次氧化铁皮结构从外到里分别为Fe_(2)O_(3)、Fe_(3)O_(4)和FeO,由于FeO中的阳离子空位密度大,导致其比例最大,并且随着轧制温度增加,氧化铁皮中的FeO层厚度逐渐增厚,并且其比例也逐渐增加。通过模拟连续冷却试验发现氧化铁皮结构转变关系呈现出"C"曲线的形式。在450~550℃温度范围内卷取时,FeO发生共析反应程度达到峰值,同时可以看出在高温下卷取可以有效抑制共析转变的发生。通过大量的试验研究表明,获得以先共析Fe_(3)O_(4)为主的完整氧化铁皮的结构类型,是有效提高热轧钢材耐蚀性的主要控制方向。因此在国内某钢厂热连轧生产线进行了基于氧化铁皮控制的耐蚀性工艺试轧试验和盐雾试验,结果表明,氧化铁皮完整致密,并且其结构类型主要为先共析Fe_(3)O_(4),因此利用轧制工艺调整改变钢板表面氧化皮结构,钢材耐蚀性能得到显著提高。According to the actual working conditions of hot rolling production process,the evolution law of triple oxide iron sheet in hot rolling and coiling stage is systematically studied,aiming at improving the corrosion resistance of steel by adjusting the hot rolling production process to control the structure of oxide iron sheet and using the oxide iron sheet generated after hot rolling as protective barrier without increasing the production cost.The experimental results show that at different rolling temperatures,the structure of tri-oxide iron sheet is Fe_(2)O_(3),Fe_(3)O_(4)and FeO from the outside to the inside,and the proportion of FeO is the largest due to the high density of cation vacancy in FeO.With the increase of rolling temperature,the thickness of FeO layer in the iron sheet is gradually thickened,and the proportion is also gradually increased.By simulating the continuous cooling experiment,it is found that the transformation relationship of the oxide sheet structure is in the form of"C"curve.In the temperature range of 450-550℃,the eutectoid reaction degree of FeO reaches the peak,and it can be seen that the eutectoid transformation can be effectively inhibited by coiling at high temperature.A large number of experimental studies have shown that obtaining the structure type of complete oxide sheet with pro-eutectoid Fe_(3)O_(4)is the main control direction to improve the corrosion resistance of hot-rolled steel effectively.So this article in a domestic steel strip production line based on the corrosion resistance of iron oxide control process to try rolling test and salt spray test,the results show that full dense iron oxide,and its structure type is mainly pro-eutectoid Fe_(3)O_(4),so use of rolling technology to adjust the changing structure of the steel plate surface scale,steel corrosion resistant performance is improved significantly.

关 键 词：氧化铁皮 轧制温度 卷取温度 共析转变 耐蚀性能 

分 类 号：TG335.11[金属学及工艺—金属压力加工] TG174.4