2009 Volume 50 Issue 7 Pages 1832-1837
The present study was carried out to evaluate the microstructure and mechanical properties of Inconel 600 subjected to laser-assisted hybrid friction-stir welding (HFSW). In this process, friction-stir welding (FSW) was performed at a constant speed (400 rpm) while a 2-kW YAG laser preheated the material just in front of the rotating tool. We found that HFSW was 1.5 times faster than conventional FSW. In addition, analysis of the grain boundary character distribution by electron back scattered diffraction (EBSD) showed that the increased welding speed and dynamic grain recrystallization caused the average grain size to decrease from 5.5 μm (in the base material) to 3.2 μm (in the stir zone of the welded specimen). This grain refinement led to 30% and 10% improvements in microhardness and tensile strength, respectively.