A Meshing Framework for Digital Twins for Extrusion based Additive Manufacturing

Abstract

Additive manufacturing (AM) allows for manufacturing of complex three-dimensional geometries not typically realizable with standard subtractive manufacturing practices. The internal microstructure of a 3D printed component can have a significant impact on its mechanical, vibrational, and shock properties and allows for a richer design space when this is controllable. Due to the complex interactions of the internal geometry of an extrusion-based AM component, it is common practice to assume a homogeneous behavior or to perform characterization testing on the specific toolpath configurations. To avoid unnecessary testing or material waste, it is necessary to develop an accurate and consistent numerical simulation framework with relevant boundary value problems that can handle the complicated geometry of internal material microstructure present in AM components. Herein, a framework is proposed to directly create computational meshes suitable for finite element analysis (FEA) of the fine-scale features generated from extrusion-based AM tool paths to maintain a strong process-structure-property-performance linkage. This mesh can be manually or automatically analyzed using standard FEA simulations such as quasi-static preloading, modal analysis, or thermal analysis. The framework allows an in-silico assessment of a target AM geometry where fine-scale features may greatly impact quantities of design interest such as in soft elastomeric lattices where toolpath infill can greatly influence the self contact of a structure in compression, which we will use as a motivating exemplar. This approach greatly reduces the waste of both time and resources consumed through traditional build and test design cycles for non-intuitive design spaces. It also further allows for the exploration of toolpath infill to optimize component properties beyond simple linear properties such as density and stiffness.