Effect of friction stir welding parameters on the microstructure and microtexture evolution of SAF 2205 stainless steel

The present study investigates the influence of different welding parameters of welding and rotational speeds on the microstructure and the texture in the stir zone (SZ) during friction stir welding (FSW) of a SAF 2205 duplex stainless steel. The FSW process was conducted using a WC- based tool with welding speeds ranging 50-350 mm/min and rotational speeds ranging 400-800 rpm. Microstructure characterization and textural studies showed that fine and dynamically recrystallized grains developed through the microstructure of the SZs and the grain size of the developed microstructures in the SZs is decreased with increasing the welding speed and/or with decreasing the rotational speeds. The intensity of the resultant simple shear texture developed in the SZs increased with increasing the rotational speed and/or with decreasing the welding speeds. Increasing the welding speed tends to weaken the intensity of shear texture and finally randomize it. Therefore, the contribution of rotational speed in formation of simple shear texture in the SZs of the processed materials is greater than that of welding speed. (C) 2019 Elsevier B.V. All rights reserved.