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8 Keyhole and Weld Pool Dynamics in Laser Welding with Filler Wires
(f) Quasi-steady state
(b) t=1.6 ms
(a) Initial boundary condition of the wire composition
(c) t=3.2 ms
(d) t=4.8 ms
(e) t=6.4 ms
Fig. 8.26 Dilution process of wire composition to the weld pool on the upper surface of the moving
weld pool
the wire composition is spreading in the weld pool. Both convection and spreading
interact with each other, to finally reach a relatively steady state. Figure 8.27 is the
concentration distribution change diagram of wire composition on certain section
near the weld joint. The speed characteristics of the moving weld pool on the section
are shown in Fig. 8.27d. As shown in the figure that, the wire composition gradually
dilutes the parent metal from the edge of the moving weld pool to the depth direction.
Due to very low speed, at the vortex of the edge, the concentration value of the wire
composition is higher than that in other positions. Generally, in the upper part of
8 Keyhole and Weld Pool Dynamics in Laser Welding with Filler Wires
(f) Quasi-steady state
(b) t=1.6 ms
(a) Initial boundary condition of the wire composition
(c) t=3.2 ms
(d) t=4.8 ms
(e) t=6.4 ms
Fig. 8.26 Dilution process of wire composition to the weld pool on the upper surface of the moving
weld pool
the wire composition is spreading in the weld pool. Both convection and spreading
interact with each other, to finally reach a relatively steady state. Figure 8.27 is the
concentration distribution change diagram of wire composition on certain section
near the weld joint. The speed characteristics of the moving weld pool on the section
are shown in Fig. 8.27d. As shown in the figure that, the wire composition gradually
dilutes the parent metal from the edge of the moving weld pool to the depth direction.
Due to very low speed, at the vortex of the edge, the concentration value of the wire
composition is higher than that in other positions. Generally, in the upper part of