Mr. Yonatan Markman - M.Sc. Candidate
15/03/2026
אודיטוריום ע"ש דויד וואנג, בניין מידן, קומה 3
13:30
PolyJet is a photopolymer-based additive manufacturing (AM) technology distinguished by high print resolution and multimaterial jetting capability, making it particularly suitable for complex load-bearing and mechanically programmable components. Realizing such architectures, however, requires a constitutive description of the material’s mechanical response and its intrinsic orientation-dependent anisotropy. To this end, this work investigates the tensile Print Orientation Anisotropy (POA) of RGD5131 “Digital ABS Plus”, a PolyJet build material produced via patterned co-jetting of two base resins. As-printed dogbone specimens manufactured in six distinct orientations revealed pronounced sensitivity to “face-on” vs. “edge-on” alignment relative to the build platform. Face-on specimens consistently outperformed edge-on counterparts in modulus and yield strength while maintaining comparable ductility, regardless of alignment with the principal build axes. Constitutive fitting using the Boyce–Parks–Argon model for glassy polymers provided a physically meaningful framework for interpretation, suggesting a higher effective crosslink density and lower susceptibility to moisture plasticization in face-on specimens. However, desiccation and thermal post-treatments produced a contrasting trend: face-on specimens showed marked increases in stiffness and strength accompanied by reduced ductility, whereas edge-on specimens exhibited only minor changes. To reconcile these observations, a hypothesis is proposed attributing the anisotropy to differences in local thermal history, illumination dose, and reaction environment, promoting distinct network architectures in face-on and edge-on RGD5131 specimens. These findings demonstrate that macroscopic part geometry directly influences final material structure and properties in PolyJet AM, with important implications for the reliable mechanical programming of load-bearing components.