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5 Dynamic Behaviors of Metal Vapor/Plasma Plume …
(a) 0.350ms
(b) 1.841ms
(c) 2.990ms
(d) 5.308ms
(e) 15.277ms
(f) 20.844ms
Fig. 5.5 Evolution of density distribution of metal vapor with time in the keyhole (P = 1.5 kW, V
= 3 m/min)
5.308 ms, 15.277 ms and 20.844 ms) with laser power at 1.5 kW and welding speed
at 3 m/min. (The black line represents the outline of the keyhole, the inside of the
keyhole indicates the density distribution of the metal vapor, and the outside indicates
the density distribution of the weld pool and the unmelted substrate). As we know
from the state equation of ideal gas ρ = p/R a T , under the conditions of uneven