Detection and analysis of weld penetration in stationary TIG arc welding — a preliminary study

Observing molten pool surface oscillations during keyhole processing in laser powder bed fusion as a novel method to estimate the penetration depth

“…Molten pool fluctuations have also been studied by means of acoustic emission although this approach suffers from noise in industrial environments due to the low pressure of the generated sound waves [50][51][52]. The correlation between surface ripples and under-surface molten pool geometry was extensively studied in literature for the GTA welding technology through arc voltage monitoring [53][54][55][56][57][58][59][60][61][62][63]. On the other hand, a correlation between molten pool surface oscillations and penetration depth has not yet been investigated for the Laser Powder Bed Fusion technology.…”