Feasibility investigation of laser welding aluminum alloy 7075-T6 through the use of a 300 W, single-mode, ytterbium fiber optic laser

Inherent instability investigation for low speed laser welding of aluminum using a single-mode fiber laser

“…The welding process at this low speed is no longer consistent with the prediction of a theoretical 2D heat transfer model, which has been shown to be in satisfactory agreement with experimental data for laser welding of different materials at higher speeds (Lankalapalli et al, 1996;Paleocrassas and Tu, 2007).…”

“…It was found that nitrogen gas was more effective than argon in minimizing or even preventing porosities. Paleocrassas and Tu (2007) investigated low speed welding of aluminum alloy 7075-T6 using a 300-W, single-mode, ytterbium fiber laser for speeds from 1 mm/s to 10 mm/s. Several metrics were developed to characterize the process efficiency.…”

“…In addition, in the next section, we further quantify the process instability in terms of the process efficiency. Paleocrassas and Tu (2007) proposed metrics to characterize welding process efficiency. One such metric was defined as keyhole fluence per weld length (KF) which has since been slightly modified and is redefined as follows:…”

“…As a result, the "Global Efficiency" defined here is significantly lower. Readers are referred to Paleocrassas and Tu (2007) for more details in these metrics. Table 1 lists the EWEs, global efficiencies, and power efficiencies for the data shown in Fig.…”

Fatigue crack fusion in thin-sheet aluminum alloys AA7075-T6 using low-speed fiber laser welding

“…With these assumptions, the model is only applicable to steady state laser welding processes with conical shaped keyholes. However, it has been shown that this model is in satisfactory agreement with experimental data for characterizing laser welding of different materials at a wide range of speeds and powers (Lankalapalli et al, 1996;Paleocrassas and Tu, 2007).…”