Magnetic modulation of keyhole instability during laser welding and additive manufacturing
Research Complex at Harwell · University College London · +4 more institutions
Abstract
Keyhole instability during laser welding and laser powder bed fusion (LPBF) can cause keyhole collapse and pore formation. Using high-speed x-ray imaging, we demonstrate that the flow vortex-induced protrusion on the rear keyhole wall is crucial in initiating keyhole instability. Applying a transverse magnetic field suppresses the keyhole instability by driving a secondary thermoelectric magnetohydrodynamics (TEMHD) flow that alters the net flow vortex. This minimizes protrusions and large-amplitude keyhole oscillations. The suppression effectiveness depends on the laser scanning direction relative to the magnetic field orientation because this controls the Seebeck effect-induced Lorentz force's direction. We…
Citation impact
- FWCI
- 36.40
- Percentile
- 100%
- References
- 57
Authors
10Topics & keywords
- Keyhole
- Welding
- Instability
- Modulation (music)
- Laser
- Materials science
- Optics
- Metallurgy