Extrusion Deposition Additive Manufacturing (EDAM) is a technology where 3-Ddigital objects are manufactured extruding beads of molten material in a layer-by-layerbasis. This technology offers the flexibility for processing pelletized material, and thusa semi-crystalline polymer highly-filled with carbon fiber has been used for printing.Significant technology improvements in the EDAM technology have been maderecently, however, the design of the printing strategy is still mostly driven by empiricaldevelopment. Hence, there is a need for simulation tools that capture the phenomenainvolved in the EDAM process to drive the development and optimization of thistechnology. Currently, one limitation of printed parts in terms of mechanical propertiesis the strength of the interface developed between printed layers. Therefore, the focusof this work is to couple the phenomena involved in the bonding process of adjacentlayers to predict the degree of bonding, such as the temperature history, the melting andcrystallization of the semi-crystalline polymer and the diffusion of polymer chains. Themodels utilized to describe these phenomena and their couplings were implemented ina UMATHT user subroutine in Abaqus to predict the evolution of the degree of bondingduring the EDAM process. The effects of the couplings implemented in this approachare demonstrated by predicting the evolution of the degree of bonding throughout thesimulation of the printing process of a geometry with sections that undergo differentcooling and crystallization rates.
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