High Temperature Oxidation Behavior of 439 Ferritic Stainless Steel at Different Temperatures

Abstract In recent years, due to the installation of selective catalytic reduction (Selective Catalytic Reduction, hereinafter referred as SCR) devices, high temperature oxidation failure has occurred frequently in automobile exhaust systems. To explore its mechanism, this paper takes 439 ferritic stainless steel which is often used pipes an example and uses XRD, SEM, EDS experimental methods study behavior at 700 °C, 800 °C 900 °C. The results show that oxide layer becomes thicker degree increases with increase working steel. products different temperatures are different. When phase structure on surface sample Cr 2 O 3 Fe , dense uniform. As rises sintered together, needle-like appears film. inner outer layers, shell structure, generated FeO, other iron oxides, very serious. At junction substrate, there particles such SiO TiO Nb a positive effect oxidation.