Improving the high-temperature oxidation resistance of Fe-18Cr-8Ni austenitic stainless steel by cold-rolling treatments

Abstract

The effect of different degrees of cold rolling on the short-term oxidation behavior of Fe-18Cr-8Ni stainless steel oxidized at 1000 °C in N2-21 vol%O2 for 3 h was investigated. The results show that cold rolling deformation reduces the grain size and coincident site lattice (CSL) grain boundary fraction of the alloy. When the deformation exceeds 20%, the oxidation mechanism changes from internal to external oxidation. And the critical concentration of Cr and Si required for forming the protective oxide scale decreases. The formation of continuous Cr2O3 and SiO2 layers on the alloy prevents the diffusion of oxygen from the surface to the matrix. The cold-rolling treatments improve the oxidation resistance of the Fe-18Cr-8Ni austenitic stainless steel at 1000 °C.

Keywords

• Fe-Cr-Ni
• Cold rolling
• High-temperature oxidation resistance
• Electron backscattering diffraction
• Oxidation mechanism