Stian Romberg, graduate student in the Department of Mechanical, Aerospace, and Biomedical Engineering, recently received recognition for his research in large-scale thermoset additive manufacturing. The research, being done in collaboration with the Polymer Materials Development team at Oak Ridge National Laboratory’s Manufacturing Demonstration Facility, has the potential to address some of the major shortcomings of thermoplastic materials in large-scale printing applications, including z-direction properties, print resolution, and cost.
Romberg’s first-author conference paper, “Large-scale Additive Manufacturing of Highly Exothermic Reactive Polymer Systems,” submitted to the Society for the Advancement of Material and Process Engineering (SAMPE) 2019 was selected for additional publication in the October 2019 edition of the SAMPE Journal.
This work studies the novel interactions between curing and exothermic behavior during the printing process and proves the feasibility of large-scale thermoset printing. Results of this research will enable more rapid adoption of the new technology into industrial applications.
Additionally, Romberg contributed significantly to a second conference paper, “Large-Scale Reactive Extrusion Deposition of Sparse Infill Structures with Solid Perimeters,” led by ORNL’s Chris Hershey, which received publication in the Journal of Advanced Materials–2019 Best Papers Collection for the Composites and Advanced Materials Expo (CAMX) 2019.
This communication demonstrates a method to seamlessly transition from sparse infill to a fully dense, machinable surface. This innovation streamlines production of lightweight, large-scale tooling components, and further demonstrates the promise of large-scale thermoset printing.
As he pursues his PhD, Romberg plans to study the manufacturing challenges and mechanical properties of large-scale cellular structures.
He hopes to identify more efficient and robust ways to create low density, high-performance structures for use in energy applications and composite tooling. Romberg is working under the direction of Assistant Professor Brett Compton. In addition to Hershey, ORNL team members include John Lindahl, William Carter, Alex Roschli, and group leader Vlastimil Kunc.
By: Kathy Williams