On the formation of grain structure during friction stir welding of duplex stainless steel

Electron back-scattered diffraction was used to analyze the microstructure and texture characteristics in a duplex stainless steel subjected to friction stir welding. In the stir zone (SZ), a continuous dynamic recrystallization (CDRX) was evidenced for ferrite, while it was suggested that a static recrystallization together with CDRX may occur for austenite. Moreover, the variations of grain size and textural features proved that higher plastic deformation in the advancing side of the SZ produced the finest recrystallized grains there.