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8 Keyhole and Weld Pool Dynamics in Laser Welding with Filler Wires
as a function of time. It can be seen from the figure that in the 0–5 ms stage, the two
curves change in a very similar way, but in the 5–15 ms stage, the maximum speed
of the weld pool changes dramatically in the event of large wire diameter. It can be
concluded that excessive large diameter of the wire will weaken the stability of the
weld pool in the process of laser welding with filler wires.
The foregoing simulation results indicate that when the wire enters the weld pool
in free transition mode, the excessive large diameter of the wire will weaken the
stability of the transient keyhole and the moving weld pool.
(d) Keyhole longitudinal-section
morphology
(e) Weld pool morphology
(f) Free interface morphology
(c) Free interface morphology
(b) Weld pool morphology
(a) Keyhole longitudinal-section
morphology
Fig. 8.8 Comparison of the results at the welding moment of 13.59 ms under different wire
diameters in free transition process
Fig. 8.9 Curve of maximum
speed absolute value-time
function of the moving weld
pool under different wire
diameters in free transition
mode
Time/ms
Maximum speed/(m/s)
Additive diameter of 0.9 mm
Additive diameter of 1.2 mm