Experimental Study of the Mechanical Properties of 3D Printed PolyJet Test Specimens

Additive manufacturing has become an essential production technology for rapid prototyping and low-volume manufacturing of functional engineering components. Among the available additive manufacturing processes, PolyJet technology offers high dimensional accuracy, good surface quality, and the ability to fabricate complex geometries using engineering photopolymer materials. This study experimentally evaluates the mechanical behaviour of Digital ABS Plus specimens manufactured by PolyJet technology using an Objet260 Connex3 3D printer. Tensile tests were performed in accordance with BDS EN ISO 527-2:2012, while Charpy impact tests were conducted in accordance with ISO 179-1:2010. The influence of manufacturer-recommended thermal treatment on tensile properties was investigated, and the effect of three different printing orientations on impact strength was analysed. In addition to the experimental investigation, a statistical assessment of the measured data is introduced to evaluate the repeatability and reliability of the obtained results. Average values, standard deviations, variances and relative measurement errors are considered for the experimental series. The results show that thermal treatment produces a moderate increase in tensile strength without substantially changing the elastic modulus, whereas printing orientation has a pronounced influence on impact strength due to the anisotropic layered structure produced by the PolyJet process. The study provides engineering data for selecting suitable printing orientations and post-processing conditions when manufacturing functional Digital ABS Plus components.