Transmission Electron Microscopy Study on the Precipitation Behaviors of Laser-Welded Ferritic Stainless Steels and Their Implications on Intergranular Corrosion Resistance

The intergranular corrosion susceptibility of ferritic stainless-steel weldments is strongly dependent on chromium carbide precipitation phenomena. Hence, stabilization widely used to mitigate the aforementioned precipitation. In contrast, has proved ineffective fully prevent due segregation unreacted during solid-state heat-treatments. To analyze behavior 17 wt.-% stainless steels laser welding, sheets unstabilized and titanium-stabilized were welded in a butt joint configuration characterized with special consideration by means transmission electron microscopy. While exhibit pronounced precipitate formation at grain boundaries, titanium-stabilization leads titanium precipitates without adjacent segregation. However, tests reveal three distinctive mechanisms within investigated based their inherent behaviors. light formation, it evident that immersion sulfuric acid media dissolution either boundaries or boundary vicinity. As result, residual mechanical strength substantially degraded.