终轧温度和卷取温度对汽车大梁钢氧化铁皮特征的影响

Effects of Finish Rolling Temperature and Coiling Temperature on Oxide Scale Characteristics of Automobile Beam Steel

通过SEM(扫描电镜)和IPP软件研究了不同终轧温度和卷取温度下汽车大梁钢的氧化铁皮厚度、微观结构。结果表明,终轧温度为800~920℃时,汽车大梁钢的氧化铁皮微观结构均为残余FeO+先共析Fe3O4,随着终轧温度的升高,氧化铁皮平均厚度增加,Fe O比例增加,先共析Fe3O4比例降低。卷取温度为530~650℃时,氧化铁皮组织中存在共析组织(Fe3O4+Fe),随着卷取温度的升高,汽车大梁钢的氧化铁皮平均厚度增加,FeO比例增加,先共析Fe3O4比例增加,共析(Fe3O4+Fe)比例降低。

The thickness and microstructure of iron oxide scale at different finishing and coiling temperatures were studied by SEM and IPP software. The results show that when the final rolling temperature is 800-920℃, the microstructure of iron oxide scale of automobile beam steel is residual FeO and pre-eutectoid Fe3O4. With the increase of finish rolling temperature, the oxide scale’s thickness and proportion of FeO increase, and the proportion of Fe3O4 decreases. When the coiling temperature is 530-650℃, the microstructure of oxide scale contains eutectoid(Fe3O4+Fe), with the increase of coiling temperature, the oxide scale thickness, proportion of FeO and pre-eutectoid Fe3O4 increase, while the proportion of eutectoid(Fe3O4+Fe) decreases.