I will be presenting at NASA Thermal Protection System (TPS) and Materials

Title: Mechanical reliability of fused deposition modeled materials

Date: Monday, July 30
Time: 2:00pm
Location: NASA Ames N229/R215

Abstract: Additive manufacturing (AM) is increasingly used for space, defense, transportation, and consumer product applications. Among various AM techniques, fused deposition modeling (FDM) is most common one that can produce polymer, composite, metal, and ceramic materials. However, FDMed materials contain pores between and inside the deposited beads. In addition, pores can be intentionally included in an FDMed design to decrease weight or to add functionality, such as heat or mass transport. These pores reduce mechanical properties and introduce variations in mechanical properties, i.e., lower mechanical reliability. Despite the increasing use of FDM, the effect of porosity on the mechanical behavior of FDMed materials are unclear. Our recent work showed that intentional vibrations or biomimetically engineered deposition path can be used to double Weibull modulus of FDMed polymers and polymer matrix composites. In this talk, I will discuss the origins of the mechanical reliability in ideal 2D porous ceramics and deviations from Weibull statistics. In addition, I will detail how we can improve toughness of porous ceramics based on our new knowledge of polymer/composite AM. Biomimetic meso-structure and vibration-assisted FDM approaches will be described to improve reliability in FDMed materials.

Posted 18th July 2018 by Ozgur Keles