Effect of anodizing on pulsed Nd:YAG laser joining of polyethylene terephthalate (PET) and aluminium alloy (A5052)

A series of laser joining experiments between polyethylene terephthalate (PET) and aluminium alloy (A5052) were conducted to investigate the effect of anodizing on A5052 surface on dissimilar materials used in joining. In this study, PET/A5052 joints with anodized A5052 surface exhibited greater shear strength compared to PET/A5052 joints without anodizing. The shear strength of the joints was increased with increasing of heat input and pulse duration. This indicates that the anodizing process could improve shear strength of the laser joining specimens. Significant molten pools were formed in both PET/A5052 (anodized) and PET/A5052 (as-received) joints except for PET/A5052 (as-received) sample joined at the lowest heat input and pulse duration. For the test results from laser joining under different pulse duration at the constant heat input, it was shown that joining behaviour was dominantly controlled by heat input and not by pulse duration.