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4 Simulation of Transient Keyhole and Weld Pool
Fig. 4.20 Variation curve of
the penetration depth with
welding time
Time/ms
Penetration depth (mm)
Fig. 4.21 Variation curve of
the weld pool size with time
Time/ms
Size of weld pool (mm3)
influence on the variation of the keyhole depth, and due to the fact that the variation
of keyhole depth indicates the keyhole instability, the surface tension has important
influence on the keyhole stability; ➃ compared with the keyhole dimension, the
variation of the weld pool dimension during the initial welding phase under the
studied technical condition is not sensitive to the variation of surface tension size.
4.3.1.3 Influence of Thermal Capillary Force on Coupling Between
Keyhole and Moving Weld Pool
In this section, we compare and study the transient coupling of keyhole and weld
pool with the surface tension temperature coefficient of −0.5 and −0.1 N/(m K).
In addition to the surface tension temperature coefficient, other parameters are the
same as the parameters in Sect. 4.2.2.