| Title |
Effect of Ring Beam Power on Microstructure and Mechanical Properties in Al-Cu Lap Joints
by Dual-Beam Laser Welding |
| Authors |
유채은(Chae Eun You) ; 윤성민(Seong Min Yun) ; 강남현(Namhyun Kang) ; 김용(Yong Kim) ; 이제인(Je In Lee) |
| DOI |
https://doi.org/10.3365/KJMM.2026.64.1.14 |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
Al-Cu lap joint; Dissimilar welding; Dual-beam laser; Fatigue; Mechanical properties; Microstructure |
| Abstract |
Substantial efforts have been devoted to laser welding techniques to join Al and Cu in battery packs
because the formation of intermetallic compounds during fusion welding degrades both the electrical and
mechanical properties of the welds. In this study, a dual-beam laser with a fixed core beam power (700 W)
was employed for the dissimilar welding of Al and Cu thin sheets, and the ring beam power was adjusted
to optimize the microstructure and mechanical properties of the lap joints. The Cu base metal was partially
penetrated at ring beam powers below 500 W, while the Cu sheet was fully penetrated at ring beam powers
above 700 W. At the ring beam power of 300 W, the formation of intermetallic compounds was suppressed
in the Al fusion zone due to the lower recoil pressure of the melt pool. However, a ring beam power above
700 W resulted in the formation of intermetallic compound layers at the Cu fusion line. Resistance to crack
propagation along the interface between the Cu fusion zone and the heat-affected zone was revealed to be
crucial to improving the mechanical properties of the Al-Cu lap joints. The highest tensile shear strength and
improved fatigue life was obtained at the ring beam power of 300 W. Results demonstrated that the dualbeam
laser welding could effectively control the formation of intermetallic compounds in the fusion zone and
enhance the mechanical performance of the welds. |