热轧钢板红锈氧化铁皮形成机制及改进措施

Formation Mechanism and Improvement Measures of Red Rust Iron Oxide Skin of Hot-Rolled Steel Plate

在现场取样进行红锈氧化铁皮的宏观形貌、微区化学成分、组织结构及O/Fe质量百分含量的测试分析,发现钢中的Si与Fe生成的2FeO.SiO2化合物是形成红锈的主要原因。红锈氧化铁皮中的O/Fe质量百分比由内表面向外表面逐渐增加,内表面结构比较疏松,外表面结构比较致密。通过采用降低钢种硅含量,降低轧制过程温度和改善层流冷却工艺等措施有效地控制了氧化铁皮的性质和结构,从而避免了红锈氧化铁皮的产生。

Macro-morphology,micro-chemical composition,structure and the mass percent of O/Fe of the red rust iron oxide skin of automotive beam steel were investigated by samples collected in factory.The results show that 2FeO·SiO2 compounds,which are formed by the Si and Fe in steel,were the main reason for the formation of red rust.The mass percent of O/Fe of the red rust iron oxide skin increases gradually from the inside out with more loose structure of the inner surface and outer surface structure more compact.The nature and structure of iron oxide skin are controlled by lowering Si content,reducing the rolling temperature and improving the laminar cooling process,thus avoiding the production of red rust iron oxide skin.