Beneficial effect of cold-working on high temperature oxidation resistance of austenitic stainless steel

The effect of a pre-straining on oxidation resistance of a low stacking fault energy austenitic stainless steel, Fe-17.5Cr-8.1Ni, was investigated at 830 degrees C in O-2 for 12 days. A decrease of the oxidation rate has been observed compared to the as-received material. For the first hours of oxidation, the martensitic deformed zone was transformed into numerous fine grains supplying a network of Cr fast diffusion paths. The high density of oxide nucleation sites related to the reverted martensite resulted in a fine-grained oxide scale which has limited the transport of scale-forming elements and moderated the long-term Cr consumption.