Direct welding of glass and aluminum alloy using nanosecond fiber laser with beam oscillation

In this work, glass and aluminum alloy were directly welded using a novel process of nanosecond fiber laser with beam oscillation. The feasibility of achieving reliable joining of glass and aluminum alloy without surface polishing or external pressure was explored via changing the beam oscillation strategy. The results showed that a defect-free glass/aluminum alloy joint could be fabricated with a 40 μm lap gap using optimized parameters: a laser power of 25 W, a scanning speed of 50 mm/s, an oscillation frequency of 750 Hz, and an oscillation amplitude of 150 μm. The welded joints exhibited a maximum shear strength of 10.95 MPa, which is 6 times higher than that without beam oscillation. Fractographic analysis results showed that beam oscillation homogenized laser energy distribution, which could result in an uniform melting and intermixing of glass and aluminum alloy. The enhanced strength of the weld joint was attributed to the improved mechanical interlocking and reduced cracks in the glass modification zone. This work presents a reliable approach for the direct joining of glass and aluminum alloy without the need for surface polishing or external pressure, ensuring high welding efficiency.