Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Fusion Bonding of Fiber Reinforced Semi-Crystalline Polymers in Extrusion Deposition Additive Manufacturing" By Eduardo Barocio Purdue MSE Ph.D. Final Exam Advisor: Professor R. Byron Pipes ABSTRACT Extrusion Deposition Additive Manufacturing (EDAM) is a large-scale Additive Manufacturing (AM) technology able to fabricate parts from the desktop scale to the size of a full vehicle. Fiber reinforced polymers have been the primary enabler for this steep transition by reducing the thermal expansion and increasing the stiffness of printing materials. The EDAM process consists of depositing beads of molten material in a layer-by-layer manner, thus large temperature gradients develop during part manufacturing. Further, shear flow introduced during material extrusion and deposition orients fibers dominantly along the print direction. In the absence of fibers reinforcing the interface between adjacent layers, the bond developed by the polymer matrix is the primary mechanism governing the interlayer mechanical properties. The combination of residual stresses due to anisotropy and temperature gradients with weak interlayer bonding can lead to delamination of parts during manufacturing. Hence, there is a need for predictive simulation tools to mitigate the empirical process of determining printing strategies that lead to crack free parts. Significant contributions were made towards this objective by developing simulation tools for predicting the evolution of temperature and interlayer strength during part manufacturing. The continuous deposition of material is replicated virtually utilizing a framework developed previously for EDAM process simulation. A suite of user-defined subroutines in Abaqus(c) was utilized for implementing different mechanisms of heat transfer as well as a model for fusion bonding. Methods for characterizing not only the properties of printing materials for EDAM process simulations but also the processing conditions used in the EDAM process are presented. Additionally, the Composites Additive Manufacturing Research Instrument (CAMRI) was developed to investigate the physical phenomena dominating the EDAM process. Printed composite tooling for high-temperature autoclave and compression molding composites manufacturing has been the primary demonstrator for this technology. Date: Thursday, November 29, 2018 Time: 2:00 P.M. Place: IMI 130