Positron Annihilation Lifetime Spectroscopy of ABS Objects Manufactured by Fused Deposition Modelling

Positron annihilation lifetime spectroscopy was used to study acrylonitrile butadiene styrene (ABS) specimens manufactured using fused deposition modelling to explore possibilities of identifying differences in molecular structure. The set of specimens was prepared including square tiles and long rectangular tiles (100 mm and 200 mm long) with all filament roads parallel to the longer edge. All types of tiles were produced with various infill line distance parameter resulting in different overlapping of the roads in horizontal and vertical directions. The slight increase of the ortho-positronium lifetime indicating increase of the mean free volume radius was observed for the longest tiles for which influence of weld interface is expected to be most pronounced. No differences were observed for different infill line distance parameters.