Glass to aluminum joining by forming a mechanical pin structure using femtosecond laser

Abstract

The joining of dissimilar materials is a widely used procedure with applications in many industries. While laser welding of such materials has gained traction interest recent years, this has intrinsic limitations, especially considering harsh requirements including surface roughness and weak bonding strength. This paper proposes a novel method to join Al6082 and SiO2 using a femtosecond laser to substantially reduce the requirements of material surface roughness and improve bonding strength. The proposed method involves drilling, ejection, filling and solidification, which results in forming a mechanical pin structure with some adhesive regions between Al6082 and SiO2, ensuring the two materials lock tightly. Besides, a significant tolerance of approximately 2 mm for focal positions was identified, overcoming the limitation of sensitivity of focus position in laser welding. Furthermore, over 100 MPa shear strength of Al6082-SiO2, which was comparable to the tensile strength of the aluminum alloy, was achieved. The proposed method provides a novel technique to improve the quality of products and facilitate the manufacturing process for joining dissimilar materials.