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8 Keyhole and Weld Pool Dynamics in Laser Welding with Filler Wires
Fig. 8.39 Concentration evolution process of wire composition in the longitudinal section of the
weld joint
the wire composition inside the weld joint is gradually diluted by the weld pool.
The wire composition tends to move from the edge of the weld pool to the direction
of penetration depth. As a result, a relatively high concentration area is gradually
formed on either side of the upper part and the bottom of the weld joint, which is
contrasted with the low concentration area in the middle of weld joint. The cause of
such distribution trend of the wire composition is related to the flow mechanism of
the transient moving weld pool.
The concentration of wire composition on the cross section of the weld joint at
the moment of solidification is analyzed quantitatively below. Figure 8.39f shows the
shape of the weld joint section at the moment of solidification through calculation. In
Fig. 8.39f, three positions, namely, A, B and C, are selected for virtual line scanning
to analyze the quantitative distribution of wire composition concentration in these
positions. The position of A, B and C is 0.12, 0.42 and 0.93 mm away from the surface
of the workpiece respectively. Figures 8.40, 8.41 and 8.42 show the distribution curve
of wire composition through line scanning at A, B and C positions inside the weld
joint. According to the figures, the wire composition presents a relatively orderly
distribution on the three curves, showing a trend of high on both sides and low in the
middle.
8 Keyhole and Weld Pool Dynamics in Laser Welding with Filler Wires
Fig. 8.39 Concentration evolution process of wire composition in the longitudinal section of the
weld joint
the wire composition inside the weld joint is gradually diluted by the weld pool.
The wire composition tends to move from the edge of the weld pool to the direction
of penetration depth. As a result, a relatively high concentration area is gradually
formed on either side of the upper part and the bottom of the weld joint, which is
contrasted with the low concentration area in the middle of weld joint. The cause of
such distribution trend of the wire composition is related to the flow mechanism of
the transient moving weld pool.
The concentration of wire composition on the cross section of the weld joint at
the moment of solidification is analyzed quantitatively below. Figure 8.39f shows the
shape of the weld joint section at the moment of solidification through calculation. In
Fig. 8.39f, three positions, namely, A, B and C, are selected for virtual line scanning
to analyze the quantitative distribution of wire composition concentration in these
positions. The position of A, B and C is 0.12, 0.42 and 0.93 mm away from the surface
of the workpiece respectively. Figures 8.40, 8.41 and 8.42 show the distribution curve
of wire composition through line scanning at A, B and C positions inside the weld
joint. According to the figures, the wire composition presents a relatively orderly
distribution on the three curves, showing a trend of high on both sides and low in the
middle.