Experimental Investigation on Electric Current-Aided Laser Stake Welding of Aluminum Alloy T-Joints

Abstract

Abstract:In the present study, aluminum alloy T-joints were welded using the laser stake-welding process. In order to improve the welding quality of the T-joints, an external electric current was used to aid the laser stake-welding process. The effects of the process parameters on the weld morphology, mechanical properties, and microstructure of the welded joints were analyzed and discussed in detail. The results indicate that the aided electric current should be no greater than a certain maximum value. Upon increasing the aided electric current, the weld width at the skin and stringer faying surface obviously increased, but there was an insignificant change in the penetration depth. Furthermore, the electric current and pressing force should be chosen to produce an expected weld width at the faying surface, whereas the laser power and welding speed should be primarily considered to obtain an optimal penetration depth. The tensile shear specimens failed across the faying surface or failed in the weld zone of the skin. The specimens that failed in the weld of the skin could resist a higher tensile shear load compared with specimens that failed across the faying surface. The microstructural observations and microhardness results demonstrated that the tensile shear load capacity of the aluminum alloy welded T-joint was mainly determined by the weld width at the faying surface.

Laser Welding

“…The present special issue on "Laser Welding" was a success with a total of 16 original research works published after peer-review. Different topics were discussed within this special issue: modelling and simulation of laser welding were presented in [1][2][3][4]; porosity control by means of high speed imaging and microscopy techniques was studied and discussed [5]; the effect of processing parameters on the microstructure and mechanical properties of laser-welded joints was evaluated for different metallic systems such as AZ31 alloy [6], steels [7][8][9][10], Ti-based alloys [11][12][13], and Al-based alloys [14]; and finally, dissimilar laser welding of aluminum to steel was presented [15,16].…”

Beam Offset Detection in Laser Stake Welding of Tee Joints Using Machine Learning and Spectrometer Measurements

“…In addition, being a non-contact method, LBW offers extreme flexibility in the geometry of the joint to be welded such as in the case of tee joints. Tee joints provide higher structural strength and lower weight, and stake welded tee joints have wide applications for example in marine industry [ 7 , 8 , 9 ].…”

Numerical Simulations and Experimental Validation on LBW Bead Profiles of Ti-6Al-4V Alloy

“…Advanced research is directed towards development of modeling and simulation tools, in addition to the process control in welding metallurgy (Wu et al, 2018;Ruan et al, 2018;Dal & Peyre, 2017;D'Ostuni et al, 2017;Popescu et al, 2017). Extensive studies are made on laser weld joint properties of metallic materials such as Al-based alloys (Zhang et al, 2017), AZ31 alloy (Lu et al, 2018), Al-steel (Cui et al, 2017;Casalino et al, 2017), steels (Górka & Stano, 2018;Mohammed et al, 2017;Xue et al, 2017;Evin & Tomáš, 2017), and Ti-based alloys (Zeng et al, 2017;Sánchez-Amaya et al, 2017;Caiazzo et al, 2017b). Mashinini & Hattingh (2018) have utilized LBW for joining 3 mm thick Ti-6Al-4V alloy sheets.…”