The Effect of Cr and V on the Oxidation Characteristics of Fe-V Alloy from Vanadium Slag at High Temperature

Abstract

The influence of V and Cr on the weight gain due to oxidation of Fe-V alloy from vanadium slag at 800℃ was studied. X-ray diffraction (XRD), scanning electron microscopy coupled to an energy dispersive spectrometer (SEM-EDS) and thermal gravimetric analysis (TGA) were employed to observe and analyze the oxidation products and surface morphology of Fe-V alloys. The results indicate that the oxidation kinetics curve of the Fe-V alloy, after undergoing 180 minutes of oxidation at 800 ℃, follows a linear trend. Moreover, the oxidation process is determined by the reaction rate of oxide formation. The oxidation products are Fe2O3, (Fe0.6Cr0.4)2O3, and CrVO4. The thickness of the oxide layer gradually increases with an increase in the V content. The oxide layer thickness of Fe-11V is the largest, approximately three times that of Fe-7V. Both the porous oxide layer structure and microcracks on the surface of the oxidation products play an important role in the sustained oxidation of Fe-V alloy. This work is useful for understanding the oxidation resistance of the alloy at high temperature.