• Exploring novel laser perforated metal absorbers to enhance joint properties. • Elaborating the effects of hole density on joint forming process. • Investigating fracture model of joint with perforated metal absorbers. Laser transmission welding (LTW) of thermoplastics using metallic absorbers offers a promising approach for fabricating transparent plastic components with tailored structural and functional properties. To improve forming stability and connection quality, this study introduces a novel laser perforated aluminum (Al) film absorbers. The joint properties fabricated with solid Al film absorbers were investigated, followed by a systematic examination about the effects of perforated Al film’s hole density on joint formation and mechanical properties. Results revealed that joints with solid Al film absorbers exhibited significant bubble formation in the metal bridging zone, with effective bonding largely confined to the fusion zone. In contrast, for joints with perforated Al film absorbers, observations of pores dynamics and joint morphology indicated that the holes facilitated gas release and molecular diffusion. This led to a reduction in bubbles formation and contributed to the forming of interlocking hybrid joints. Furthermore, the modified temperature distribution enhanced substrate fusion and resulted in good weld morphology. Fractographic analysis displayed PSU substrate damage and residual Al element in the bridging zone, indicating that perforation strengthened interfacial adhesion. After optimizing the process parameters, the joint shear strength increased by 59.5%. This study establishes perforated Al film absorbers as an effective strategy for regulate joint formation, enabling the production of high-performance thermoplastic joints via LTW.
Yu et al. (Fri,) studied this question.