The Fatigue and Corrosion Fatigue Behavior of Austenitic Stainless Steel AISI 304 after Deep Rolling at Various Temperatures

The austenitic stainless steel AISI 304 was deep rolled at 20 °C (RTDR), -195 °C (CTDR), and 550 °C (HTDR). The deep rolling pressures used for each deep rolling temperature were 1.0, 1.7, and 2.4 bar. From microstructural investigation, the largest compressive residual stress field was found in RTDR, and the highest amount of martensitic content and plastic deformation were found in CTDR. The strain aging effect was only found in HTDR. In the rotating bending fatigue tests, the strain aging effect after HTDR is beneficial for impeding fatigue failure. For deep rolled AISI 304, the surface hardness increases as the martensitic content rises and it slows fatigue crack initiation. Moreover, the compressive residual stress delays fatigue crack propagation. The corrosion fatigue resistance behavior of untreated AISI 304 occurs in two regions: the stress-controlled and corrosion-controlled regions. Only a stress-controlled region is present in deep-rolled AISI 304. It could be deduced that the corrosion fatigue behavior of deep-rolled AISI 304 is dependent on its fatigue endurance characteristics. Moreover, fatigue failure initiates from corrosion pits. The extent, shape, size, and type of corrosion pits are influenced by the strain-induced martensitic transformation content.