On September 29th, Prof. Douglas E. Smith, Professor of Mechanical Engineering at Baylor University, will deliver a talk as part of the SASCOM Seminar Series titled “Relating Microstructure and Processing to Adhesion Performance for Large Area Additive Manufacturing Polymer Composite Extrusion/Deposition.”

Polymer extrusion/deposition is perhaps the most popular additive manufacturing technology as it offers significant design flexibility with extensive material options at a low cost. While the introduction of chopped carbon fibers into the polymer matrix improves thermo-mechanical properties, fiber inclusions appear to be instigators for micro void nucleation in the bead microstructure, leading to inferior part performance. This presentation considers the presence of carbon fiber and its influence on micro void formation (process) during polymer composite extrusion/deposition Large Area Additive Manufacturing (LAAM). Micro CT is used to characterize the microstructure within printed carbon fiber ABS (CF-ABS) beads where correlation between fiber alignment and void formation (property) is explored for the pellet feed stock, freely extruded strand, deposited bead, and roller compacted bead. Next, fiber tip pressure within the extrusion/deposition polymer composite melt flow is evaluated with a custom multiscale finite element modeling procedure which identifies a fundamental mechanism for potential void nucleation during processing. Finally, a finite element study and fracture toughness testing are presented which highlight the dependence of interlayer bead adhesion (performance) on fiber orientation and void content.

To attend this insightful talk, please register for the Zoom session on the SASCOM website.