Enhanced mechanical properties of type AISI301LN austenitic stainless steel through advanced thermo mechanical process

The effect of annealing temperature and time on the grain size of reversed austenite and mechanical properties was studied based on AISI301LN austenitic stainless steel in this paper. Cold rolling at 0 °C was employed to obtain the strain-induced martensite, followed by annealing treatment at the temperature range of 650–900 °C for 1–20 min. The relationship between the volume fraction of strain-induced martensite and cold reduction was analyzed by Ferritescope MP30 and X-ray diffraction. The grain growth of reversed austenite was observed by FEG-SEM and the mechanical properties were determined by tensile tests and Vickers hardness tests. Austenite grain sizes under 3 μm can be obtained after annealing in the range of 700–900 °C for 1–20 min. The finest austenite grain size was produced after annealing at 700 °C for 20 min, which had a good combination of yield strength (≈830 MPa), tensile strength (≈953 MPa) and elongation (≈36%).