Ablation of selected thermoplastic polymers using an Nd:YAG laser

Abstract

This article presents the results of a study on laser ablation of selected thermoplastic polymers using an economical fiber laser with a scanning galvanometer system and an IR laser with a wavelength of λ = 1064 nm. The study aimed to develop comparative characteristics of the ablation processes of commonly used constructional thermoplastics, namely acrylonitrile butadiene styrene terpolymer (ABS), polystyrene (PS), poly(ethylene terephthalate) (PET), polylactide (PLA), and polyamide 6 (PA6). The ablation characteristics of the tested materials were determined, and the ablation depth and surface structures were calculated and presented. A comparative analysis of the contact angle, surface free energy, and strength of adhesive connections of materials modified with laser radiation and unmodified was performed. The study showed that the dynamics of laser ablation were much higher in ABS, PS, PET, and PC than in PLA and PA6. Although modification of the surface layer of the polymeric material did not have a significant impact on the surface free energy and wettability of the sample surface, it increased the strength of adhesive connections even several times (in ABS, PS, PET) with the lowest energy consumption. The results also demonstrated that some polymers, such as ABS or PS, can be effectively treated with near-infrared laser radiation of this wavelength, which is particularly important for surface layer modification and marking of details.