Stian Romberg

Biography

2025–Present
Teaching Assistant Professor
Department of Mechanical and Aerospace Engineering
University of Tennessee, Knoxville

2024–2025
Research Scientist – Mechanical Engineering
Materials Science and Engineering Division
National Institute of Standards and Technology (NIST)

2022–2024
National Research Council (NRC) Postdoctoral Research Associate
Materials Science and Engineering Division
NIST

2017–2021
Graduate Research Assistant
Department of Mechanical, Aerospace and Biomedical Engineering
University of Tennessee/Oak Ridge National Laboratory

2015–2017
Mechanical Engineer
Y-12 National Security Complex

Education

• PhD, University of Tennessee, Knoxville, Mechanical Engineering, 2021
• MS, University of Tennessee, Knoxville, Mechanical Engineering, 2019
• BS, Brown University, Mechanical Engineering, 2015

Research

• Advanced manufacturing
• Additive manufacturing
• Direct ink writing
• Polymeric semiconductor packaging materials
• Thermosets
• Epoxy composites
• Nanoparticle composites
• Yield stress fluids
• Rheology
• Raman spectroscopy
• Solid Mechanics
• Structural stability

Professional Service

• Organizer and chair of the “Electronic Packaging” session at the 51^st North American Thermal Analysis Society (NATAS) Conference, Dearborn, MI, 2025
• Lecturer of the “Rheology” short course at the 51^st NATAS Conference, Dearborn, MI, 2025
• Organizer and chair of the “Rheology” session at the 50^th NATAS Conference, Knoxville, TN, 2024
• Session chair at the Innovative Materials and Methods for Additive Manufacturing conference, Tomar, Portugal, 2024
• Moderator of the “What to expect in graduate school” discussion the American Chemical Society (ACS) Spring conference, Indianapolis, IN, 2023
• Volunteer mentor at the South Doyle Chapter of For Inspiration and Recognition of Science and Technology (FIRST) Robotics, Knoxville, TN, 2017

Awards and Recognitions

• Centrally-funded NRC Postdoctoral Research Proposal at NIST: Determining stable curing recipes for printed thermoset materials via rheo-Raman microscopy, 2021
• CAMX Best in Track Outstanding Technical Paper: Large-Scale Reactive Extrusion Deposition of Sparse Infill Structures with Solid Perimeters, 2019
• CAMX ACE Award: Large Area 3D Printer for Thermoset Materials, 2018
• 3^rd Place Poster: Student Night hosted by Oak Ridge Chapter of ASM/Center for Materials Processing, 2017
• National Science Foundation (NSF) Student Support Scholarship – Solid Freeform Fabrication Symposium, 2021
• Tickle Graduate Fellowship, 2017–2021
• Y-12 National Security Complex Quarterly Technology Transfer Honoree, 2017
• Winner of the Class of 1910 Football Trophy—awarded to the Brown senior football player with the highest GPA, 2015
• Capital One Academic All-District Football First Team, 2014
• Elected to Tau Beta Pi, 2013

Publications

Journal Articles

• S.K. Romberg, Paul Roberts, Chad R. Snyder, A.P. Kotula. (2024) “Evaluating models that predict epoxy conversion using rheological properties,” ACS Applied Polymer Materials. https://doi.org/10.1021/acsapm.4c00607.
• S.K. Romberg, A.P. Kotula. (2023) “Simultaneous rheology and cure kinetics dictate thermal post-curing of thermoset composite resins for material extrusion,” Additive Manufacturing. Vol. 71: 103589. https://doi.org/10.1016/j.addma.2023.103589.
• S.K. Romberg, C.J. Hershey, J.M. Lindahl, W.G. Carter, J. Condon, V. Kunc, and B.G. Compton. (2022) “Large-scale reactive thermoset printing: Complex interactions between temperature evolution, viscosity, and cure shrinkage,” The International Journal of Advanced Manufacturing Technology. Vol. 123: 3079-3094 https://doi.org/10.1007/s00170-022-10380-3.
• S.K. Romberg, A.I. Abir, C.J. Hershey, V. Kunc, and B.G. Compton. (2022) “Structural stability of thin overhanging walls during material extrusion additive manufacturing of thermoset-based ink,” Additive Manufacturing. Vol. 53: 102677. https://doi.org/10.1016/j.addma.2022.102677.
• S.K. Romberg, M. Islam, C.J. Hershey, M. DeVinney, C.E. Duty, V. Kunc, and B.G. Compton. (2021) “Linking thermoset ink rheology to the stability of 3D-printed structures,” Additive Manufacturing. Vol. 37: 101621. https://doi.org/10.1016/j.addma.2020.101621.
• S.K. Romberg, C.J. Hershey, J.M. Lindahl, W. Carter, B.G. Compton, V. Kunc. (2019) “Large-scale Additive Manufacturing of Highly Exothermic Reactive Polymer Systems,” SAMPE Journal. Vol. 55: 8-13. https://doi.org/10.33599/nasampe/s.19.1616.
• R. Tao, P.J. Centellas, S.K. Romberg, A.P. Kotula, G.A. Holmes, A.L. Forster, C.L. Soles, R.D. Allen, E. Cetegen, W.T. Chen, J.T. Gotro, and M.D. Poliks. (Accepted, 2025) “Material Needs and Measurement Challenges for Advanced Semiconductor Packaging: Understanding the Soft Side of Science,” IEEE Transactions on Components, Packaging and Manufacturing Technology.
• B.G. Compton, P.P. Bui, S.K. Romberg, J.W. Kemp, J.L. Reed, A. Cherry, and T.A. Schaedler. (2025) “3D-printed SiC-microfiber-reinforced polymer-derived ceramic with high strength at elevated temperature,” Journal of the American Ceramic Society. e70143. https://doi.org/10.1111/jace.70143.
• R.C. Pack, S.K. Romberg, A.A. Badran, N.S. Hmeidat, T. Yount, and B.G. Compton. (2020) “Carbon Fiber and Syntactic Foam Hybrid Materials via Core-Shell Material Extrusion Additive Manufacturing,” Advanced Materials Technologies. Vol. 5: 2000731. https://doi.org/10.1002/admt.202000731.
• J.J. Shen, M.R. Patterson, E. Marshall, J. Dvorak, S.K. Romberg, T. Schmitz. (2022) “Effects of surface treatments on ABS mechanical properties from fused filament fabrication,” Manufacturing Letters. Vol. 33: 719-731. https://doi.org/10.1016/j.mfglet.2022.07.091.

Book Chapter

• P. Scott, C. Weyhrich, C. Williams, T. Long, N.S. Hmeidat, M. Wimmer, S.K. Romberg, B.G. Compton, N. Levenhagen, M. Dadmun. (2022) “Polymeric Materials for Additive Manufacturing,” Macromolecular Engineering: From Precise Synthesis to Macroscopic Materials and Applications.

Conference Proceedings

• P.J. Centellas, S.K. Romberg, R. Tao, A.K. Landauer, K.F. Schoch, H.G. Nguyen, G.A. Holmes, G. R. Stafford, and C.L. Soles. (Accepted, 2025) “Advanced Metrology Suite for Linking Residual Stress to Fundamental Properties of Thermoset Packaging Materials,” 2025 IEEE 75^th Electronic Components and Technology Conference (ECTC). https://doi.org/10.1109/ECTC51687.2025.00078.
• S. Engmann, A.J. Gayle, S.K. Romberg, C.L. Soles, and C.A. Michaels. (Accepted, 2025) “A Dual Mode BLS/LFR Microscope for Local Mechanical Property Imaging for Semiconductor Packaging Materials,” 2025 IEEE 75th Electronic Components and Technology Conference (ECTC). https://doi.org/10.1109/ECTC51687.2025.00288.
• C.J. Hershey, J.M. Lindahl, S.K. Romberg, A.C. Roschli, B. Hedger, M. Kastura, B.G. Compton, V. Kunc. (2019) “Large-Scale Reactive Extrusion Deposition of Sparse Infill Structures with Solid Perimeters,” Composites and Advanced Materials Expo (CAMX) 2019 Proceedings.
• A. Boulger, R. Laughter, A. Rhodes, P. Mhatre, N. Tsiamis, C.J. Hershey, S.K. Romberg, J.M. Lindahl, V. Kunc. (2019) “Large-Scale Thermoset Pick and Place Testing and Implementation,” 2019 International Solid Freeform Fabrication Symposium Proceedings.
• J.M. Lindahl, A.A. Hassen, S.K. Romberg, B. Hedger, P. Hedger Jr., M. Walch, T. DeLuca, W. Morrison, S. Kim, A. Roschli, D. Nuttall, J. Czachowski, B. Post, L. Love, V. Kunc. (2018) “Large-Scale Additive Manufacturing with Reactive Polymers,” CAMX 2018 Proceedings.

Government report

• V. Kunc, C.J. Hershey, J. Lindahl, S.K. Romberg, S. Voeks, M. Adams. (2019) “Vinylester and Polyester 3D Printing,” Oak Ridge National Laboratory. https://doi.org/10.2172/1606801.

Data Publications

• S.K. Romberg, S. Lehrman, J.E. Seppala, A.P. Kotula. (2025) “Identifying the chemical gel point of thermoset composites using optimally windowed chirp measurements,” NIST Public Data Repository (PDR). https://doi.org/10.18434/mds2-3634.
• S.K. Romberg, A.P. Kotula. (2023) “Simultaneous rheology and cure kinetics dictate thermal post-curing of thermoset composite resins for material extrusion,” NIST Public Data Repository. https://doi.org/10.18434/mds2-2918.
• P.J. Centellas, S.K. Romberg, R. Tao, A.K. Landauer, K.F. Schoch, H.G. Nguyen, G.A. Holmes, G. R. Stafford, and C.L. Soles. (2025) “Data for Advanced Metrology Suite for Linking Residual Stress to Fundamental Properties of Thermoset Packaging Materials,” NIST PDR. https://doi.org/10.18434/mds2-3698.
• S. Engmann, A.J. Gayle, S.K. Romberg, C.L. Soles, C.A. Michaels. (2025) Data for A Dual Mode Brillouin/Low-Frequency Raman Spectroscopy Microscope for Local Mechanical Property Imaging for Semiconductor Packaging Materials,” NIST PDR. https://doi.org/10.18434/mds2-3725.