双相不锈钢2205热轧钢带氧化铁皮显微分析

Analysis of oxide scales microstructure of hot rolled duplex stainless steel 2205 strip

应用OM、SEM、XRD技术,分析研究了双相不锈钢2205热轧钢带氧化铁皮显微结构特征,这是决定钢带酸洗效果的本质因素之一。结果表明:热轧后钢带表面氧化铁皮存在大量的裂纹以及局部伴有氧化铁皮部分脱落,有利于酸洗;氧化铁皮厚度一般为10μm左右,但是存在局部区域氧化层增厚以及氧化铁皮向基体内部的嵌入;氧化铁皮中含有难以酸洗的铁橄榄石(Fe2Si O4)和尖晶石结构的Cr2O3·Fe O等物相,增加了钢带表面氧化铁皮酸洗去除的难度。

As one of the essential factors,the microstructure of oxide scales on the duplex stainless steel 2205,is crucial for pickling quality of the hot rolled strips. The investigation and analysis process of the microstructure of different oxide scales on the duplex stainless steel 2205 by OM,SEM and XRD was illustrated. The results show that a lot of cracks were presented on the oxide scales of hot rolled strip,accompanied by local oxide scales falling off,which helped enhancing the pickling speed;the thickness of different scales was about 10μm. However,the increasing of scale thickness and the surface roughness between the oxide scales and metallic substrates in local region caused difficult pickling of oxide scales;the complex and multiple phase composition （remained Fe2SiO4 and Cr2O3·FeO ） of oxide scales led to more chal-lenging process of pickling duplex stainless steel 2205.