模拟热轧工艺对氧化铁皮组织性能的影响  

Influence of hot-rolling parameters on the microstructure and corrosion-resistance of oxide scales

作　　者：刘胜[1] 武会宾[1] 余伟[1] 王立东[1] 蔡正旭[1] 唐荻[1] 

机构地区：[1]北京科技大学高效轧制国家工程研究中心,北京100083

出　　处：《材料科学与工艺》2013年第6期84-90,共7页Materials Science and Technology

基　　金：国家高技术研究发展计划资助项目(2012AA03A508)

摘　　要：采用热模拟实验机、场发射扫描电子显微镜、电化学测试等试验方法,研究了开轧温度、终轧温度和卷取温度对氧化铁皮组织和耐蚀性能的影响规律.研究表明:热轧钢板表面氧化铁皮由3层结构组成,即最外层Fe2O3、中间层Fe3O4和最内层FeO.随着开轧温度和终轧温度的降低,FeO先共析转变的驱动力增大,FeO在整个氧化铁皮层中的含量逐渐减少,Fe2O3和Fe3O4含量逐渐增多.随着卷取温度由650℃降低到500℃,在FeO层中析出的Fe3O4粒子数量不断增加,粒子尺寸越来越细小.析出的Fe3O4越多,氧化铁皮的耐蚀性能越高.当卷取温度降低至450℃时,FeO发生了共析转变,生成片层状Fe+Fe3O4的共析组织,这些片层状组织形成微电池,使氧化铁皮的耐蚀性能急剧降低.Abstract： Effects of start rolling temperature, finish rolling temperature and coiling temperature on the microstructure and corrosion-resistance of oxide scales have been investigated by Gleeble 3500 thermal simulated test machine, scanning electron microscopy （SEM）, polarization curves and electrochemical impedance spectroscopy （EIS）, which provides theoretical direction and technical support for optimization of processes. The results show that the oxide scale folned on the hot rolling plate is comprised of three layers ： a thin outmost hematite （Fe2O3 ） layer, an intermediate magnetite （Fe3O4 ） and a thick inner wustite （FeO） layer. With the decrease of start rolling temperature and finish rolling temperature, the driving force of FeO proeutectoid reaction is enlarged, resulting in the increase of thickness fraction of FeO gradually and the decrease of the thickness fraction of Fe2O3 and Fe3O4. With the coiling temperature decreased from 650℃ to 500℃, the amount of F%O4 precipitated in FeO layer increases and the size of these precipitates get smaller. Due to the increase of Fe3 O4, the corrosion-resistance of oxide scale is gradually improved. However, once the coiling temperature decreases to 450℃, FeO transformes to lamellar mixture Fe ＋ Fe3 O4 by eutectoid reaction. The lamellar mixture Fe ＋ Fe3 O4 makes up lots of micro- battery, resulting in the decrease of corrosion-resistance of oxide scale.

关 键 词：开轧温度 终轧温度 卷取温度 氧化铁皮 耐蚀性能 

分 类 号：TG172.3[金属学及工艺—金属表面处理]