抄録
In this report, butt welding with aluminum sheets of 0.3mm in thickness has been performed at welding speed of 1500〜6000mm/min by inverter controlled TIG welder. Aluminum sheets have been clamped between copper plates to restrain weld heat input what causes deformation for preceding area. Weld bead at high welding speed has been examined for mechanical properties. In particular, static deformed behavior of cross section of weld bead is photographed through polarization microscope. Consequently, as welding speed becomes high, deformation of weld bead has been restrained, and fatigue strength has progressed gradually until welding speed of 6000mm/min. This report has proposed that deformed behavior of weld bead affected fatigue strength.