Analysis of mechanism of plasma and spatter in CO2 laser welding of galvanized steel

In laser welding, quality, reproducibility and formability are required. Th at is the great problem in the automation of the laser welding process. The refore, construction of an on-line process monitoring system of high accura cy is requested. sThe light which is emitted from plasma and spatter in laser welding was de tected by photo-diodes. It was found that the light intensity depends on we lding speed, laser power and flow rate of assist gas. The relationship betw een the plasma and spatter and the bead shape, and the mechanism of plasma and spatter were analyzed for on-line laser weld monitoring systems. (C) 19 99 Elsevier Science Ltd. All rights reserved.