Regulation of bead formation in GMAW based on oscillat-ing-laser scanning
"8"-shaped oscillating-laser scanning was adopted in GMAW(gas metal arc welding)process to modify the weld pool flow pattern and its temperature field,and thus improve the weld bead formation.Bead-on-plate welding experiments were conducted on 6061 aluminum alloy plates.The effects of major laser scanning parameters,such as the laser-wire dis-tance,laser power and the oscillation amplitude,were experi-mentally analyzed.A high-speed camera was used to capture the process of laser scanning and the weld pool.Experimental results indicated that oscillating laser scanning could effect-ively suppress weld bead formation defects;optimal weld formation was obtained when applying oscillating-laser scan-ning across the middle part of the molten pool.Oscillating-laser scanning reduced the temperature gradients of the weld pool.The laser recoil force could drive the molten pool flow actively,and thus promote the liquid metal spreading and ef-fectively suppress irregularities in bead formation while redu-cing internal porosity and crack defects.Furthermore,the bead width could be adjusted within a certain range by adjusting the laser scanning amplitude.
oscillating-laser scanninggas metal arc weld-ingmolten pool flowbead formation
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维普
