HEMI Seminar: Amy Peterson (UMass – Lowell)

Modeling and Informatics Approaches to Advance Material Extrusion Additive Manufacturing

Amy M. Peterson
Associate Professor, Department of Plastics Engineering
University of Massachusetts Lowell

Additive manufacturing (AM) has drawn interest from fields ranging from aerospace to regenerative medicine to metamaterials. Using AM, specimens with complex internal geometries and structures can be manufactured. Despite the advantages and interest, broader use of AM is limited by poor mechanical properties, lack of reliability, and lack of expertise. We use experimental and computational approaches to better understand the underlying phenomena that control material extrusion (MatEx) AM. A simulation was developed that describes temperature throughout a build. At benchtop (FFF) scales, short times over T_g were reported, indicating limited opportunity for interlayer diffusion. Additionally, maxima in cooling rates were observed at print speeds of 10-30 mm/s, which may have implications for residual stress formation. At larger (BAAM) scales, much longer times above T_g were observed, which can lead to continued flow of extruded material and warping of the printed structure. The effects of material and processing parameters were investigated at both scales, and different trends were observed at the small and large scales. We have also applied a materials informatics approach to MatEx. Principal component analysis (PCA) of those results indicate that differences in the printer design lead to performance-critical differences in printed material structure and properties. Combined, these results indicate that designing MatEx materials and processes in concert will lead to improved structure performance, and give preliminary guidance in development of design rules.

Amy Peterson is an Associate Professor of Plastics Engineering at University of Massachusetts Lowell. Her research group studies processing-structure-property relationships in polymers and polymer composites, with a focus on interfacial phenomena in multilayered systems. She received her PhD in 2011 from Drexel University, where she was an NSF IGERT and Graduate Research Fellow. She was an Alexander von Humboldt Postdoctoral Fellow at the Max Planck Institute of Colloids and Interfaces 2011-2013 and Assistant Professor of Chemical Engineering at Worcester Polytechnic Institute 2013-2018.