Effects of Vanadium and Niobium on the Mechanical Properties and High-Temperature Oxidation Behavior of Austenitic Stainless Steels

This study focuses on the effects of vanadium and niobium microalloying elements on the mechanical properties and high-temperature oxidation behavior of austenitic stainless steels. Vanadium–niobium elements were confirmed to play an effective role in fine-grain strengthening at room temperature, achieving a tensile strength and yield strength of approximately 768.8 MPa and 464.6 MPa, respectively, with the additions of 0.32 wt% V and 0.21 wt% Nb. During the high-temperature oxidation process, the weight gain and cracking of the oxide layer increased with increasing niobium–vanadium content. The loose structure and delamination of the oxide layer during the oxidation process were caused by the enhanced internal stress of the oxide layer and the molten state of V2O5 at 850 °C.