GL-A32和B610E板坯再热温度下的氧化行为

摘要

为了解宽厚板板坯再热温度下的高温氧化行为,采用热重分析法(TGA)研究了GL-A32和B610E两种典型热轧厚板在再热温度下(1100～1200℃空气中氧化90 min)的氧化增重动力学行为,并采用扫描电镜(SEM)和X射线衍射仪(XRD)观察和分析了氧化皮的形貌与相组成.结果表明,随着温度的升高,钢铁氧化增重加剧,氧化动力学过程包含初始快速氧化和稳态氧化两个阶段;外层氧化皮主要由Fe2O3、Fe3O4和FeO组成,其组成随氧化温度的不同变化明显.在1100℃和1150℃,氧化皮呈灰黑色,伴有大面积鼓泡和局部凹凸,且较薄,容易剥离;而在1200℃下,氧化皮较厚且呈亮灰色,硬度很大.%In order to understand the high-temperature oxidation behaviors of heavy plate steels in the reheating process, the oxidation kinetics of two typical hot-rolled heavy plate products GL-A32 and B610E in the air at temperatures of 1100 ～ 1200 ℃ was measured by the thermo-gravimetric analysis method (TGA). The morphology and composition of the oxide scales were characterized by scanning electron microscopy (SEM) and X-ray diffration (XRD). The results showed that the oxidation weight-gain of the steels increased dramatically with increasing the temperature. The oxidation process could be divided into two stages, i. e., the initial rapid transient oxidation stage and the steady oxidation stage. The outer part of oxide scales was mainly composed of Fe2O3, Fe3O4 and FeO, but the composition of each phase changed significantly with oxidation temperature. The oxide scales formed at 1100 ℃and 1150 ℃ were grey-black, with blistering in large areas, thin and easy to remove. The oxide scale formed at 1200 ℃, however, was light-grey and had high hardness.