Oxidation resistance of thermo-mechanically processed austenitic stainless steel 316L in super critical water

Performance and efficiency of more advanced reactors like Super Critical Water Reactors (SCWRs) is linked to more severe service conditions. Obviously, functioning under super critical water condition needs construction materials which have superior mechanical properties and oxidation resistance. In this work, we studied effect of thermo-mechanical process on the oxidation resistance of austenitic stainless steel 316L in super critical water. Thermo-mechanical process consisted of multi-step cross-rolling at room temperature followed by annealing in 1050 ºC for 5 minutes per millimeters of thickness. Precursors then were oxidized in super critical water at 600 ºC and 25 MPa for 100, 300 and 1000 hours. Results indicated that texture is very important to oxidation resistance. Samples with {103} texture and {110} texture showed the worst and the best oxidation resistance, respectively. Results also indicated that thermo-mechanical processing improves adhesion between oxide scale and austenite due to reduction of high energy grain boundaries fraction.