(165b) Mechanical Properties of 3D Printed Thermoplastics Via Material Extrusion from Surface Topology

Defects from one layer are known to impact subsequent layers to lead to catastrophic failure of 3D printed parts using filaments. These large scale defects are generally easy to identify, but this raises the question what about minor errors in printed parts. Do minor deviations in the print on one layer lead to a quantifiable change in subsequent layers? Here, we describe how the surface topology of a final part can be used to provide insights into the mechanical properties to describe part-to-part variation even under the same printing conditions. The variance in the ultimate tensile strength (UTS) of the printed parts can be correlated with differences in the surface topology of the printed parts. We demonstrate how use of Fourier transforms provides a simple metric that describes how minor, difficult to visualize changes in the surface topology are related to the UTS. This correlation can be used to identify outlier parts and provide a route for qualification of additively manufactured parts without necessitating overdesign to address variance in the printing process. This post-print characterization does not require significant investment for each tool, nor their modification, but provides an opportunity to provide value through improving reliability. If time permits, extension of these concepts to other mechanical properties using vision transformer (ViT) for enhanced image analysis will be discussed.