Mechanical and microstructural investigation of dissimilar joints of Al-Cu and Cu-Al metals using nanosecond laser

Laser beam welding (LBW) has found wide applications in several fields, including electronics, aerospace, and automobile industries, owing to its inherent capabilities over existing welding techniques. Dissimilar laser welding is one of the challenging fabrication processes. However, joining of different materials poses challenging issues because material properties of each material interacts to give rise to hybrid system performance. In present study weld of Al-Cu and Cu-Al has been performed using Ytterbium pulsed fibre laser with a maximum laser power of 300 W. The scanning electron microscope (SEM), and energy dispersive x-ray spectroscopy (EDS) has been employed to investigate the microstructural and chemical composition of the welded joints. The EDS analysis showed the presence of possible intermetallic compounds (IMCs) like AlCu and Cu2Al in the fusion zone. The Al-Cu and Cu-Al welded joints had maximum shear strength of 295 N and 84 N, respectively. The results showed the efficacy of Al-Cu joints over Cu-Al joints. The study further demonstrated that the Al-Cu weld had a better microstructure with fewer pores and cracks than the Cu-Al welds by varying the laser powers.