Clear plastic transmission laser welding using a metal absorber

This paper presents a novel method for obtaining a clean and high-quality joint between clear plastics through transmission laser welding (TLW). In the proposed method, dye is replaced with metal as the absorber. The key factors that affect the welding quality of polyethylene terephthalate were investigated. These factors included laser input power, clamping pressure, and different absorbers (carbon black (CB), and Fe wire). Compared with the joint welded using the CB absorber, that welded using the Fe absorber was cleaner and impurity-free with more stable and higher welding strength. High welding strength was associated with the thermal conductivity of the utilized metal absorber. Results indicated that dye absorber could be feasibly substituted with metal in the TLW of clear plastic.