Analysis of mechanical strength and corrosion resistance in SS316L joints by friction stir welding

The mechanical characteristics and corrosion feature of the SS316L joints that were produced using friction stir welding were widely studied. From 450 to 750 rpm, a broad range of rotational speeds was used to create sound joints. The stir zone’s microstructures were mostly austenite and lath martensite, with no harmful phases formed. Beyond 450 rpm, increasing rotational speed increased the welded joints’ ultimate tensile strength. The ultimate tensile strength (UTS) of the base materials (BMs) was 824 ± 28 MPa at 750 rpm, or 99.5 ± 2.4% of the total. As a result of improved corrosion resistance and reduced martensite content, the FSW joints had corrosion rates associated with uniform corrosion at minimum rotational speed that were a factor of ten minimum than those in the base metal. Despite the variable findings with uniform corrosion, a high rotating speed of 750 rpm produced improved anti-pitting corrosion effectiveness. Some have hypothesized that increasing the martensitic content improved the anti-pitting corrosion ability but degraded the uniform corrosion performance.