220
8 Keyhole and Weld Pool Dynamics in Laser Welding with Filler Wires
(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. 8.17 Comparison of the results at the welding moment of 13.59 ms under different wire
diameters in free transition mode
statistical results shown in Fig. 8.18. The red line represents the maximum speed
variation curve of the weld pool with time at the additive diameter of 1.2 mm in
contact transition, while the green line represents the maximum speed variation curve
of the weld pool with time at the additive diameter of 0.9 mm in contact transition.
According to the overall tendency of the red curve in Fig. 8.18, big fluctuation
exists in the maximum speed of the weld pool with a larger diameter between 3 and
5 ms in contact transition. The analysis shows that this is because of the impact on
the weld pool due to the wire that just enters the weld pool. The overall tendency of
the two curves reveals that the larger the contact transition radius, the more dramatic
the fluctuation. In case of the additive diameter of 0.9 mm, the maximum speed of
the weld pool changes between 0.5 and 3.25 m/s in contact transition, in case of the
additive diameter of 1.2 mm, the maximum speed of the weld pool changes between
Fig. 8.18 Curve of
maximum speed absolute
value fluctuation-time
function of the moving weld
pool under different wire
diameters
Time/ms
Maximum speed/(m/s)
Diameter of 0.9 mm
Diameter of 1.2 mm
8 Keyhole and Weld Pool Dynamics in Laser Welding with Filler Wires
(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. 8.17 Comparison of the results at the welding moment of 13.59 ms under different wire
diameters in free transition mode
statistical results shown in Fig. 8.18. The red line represents the maximum speed
variation curve of the weld pool with time at the additive diameter of 1.2 mm in
contact transition, while the green line represents the maximum speed variation curve
of the weld pool with time at the additive diameter of 0.9 mm in contact transition.
According to the overall tendency of the red curve in Fig. 8.18, big fluctuation
exists in the maximum speed of the weld pool with a larger diameter between 3 and
5 ms in contact transition. The analysis shows that this is because of the impact on
the weld pool due to the wire that just enters the weld pool. The overall tendency of
the two curves reveals that the larger the contact transition radius, the more dramatic
the fluctuation. In case of the additive diameter of 0.9 mm, the maximum speed of
the weld pool changes between 0.5 and 3.25 m/s in contact transition, in case of the
additive diameter of 1.2 mm, the maximum speed of the weld pool changes between
Fig. 8.18 Curve of
maximum speed absolute
value fluctuation-time
function of the moving weld
pool under different wire
diameters
Time/ms
Maximum speed/(m/s)
Diameter of 0.9 mm
Diameter of 1.2 mm