Paper Number
AM7 

Session
Additive Manufacturing

Title
Simulation of rheological effects in processing during material extrusion

Presentation Date and Time
October 15, 2018 (Monday) 1:55

Track / Room
Track 3 / Bellaire

Authors (Click on name to view author profile)

  1. Horner, Jeffrey S. (University of Delaware, Chemical and Biomolecular Engineering)
  2. Phan, David D. (University of Delaware, Department of Chemical and Biomolecular Engineering)
  3. Coasey, Keith (University of Delaware, Materials Science and Engineering)
  4. Beris, Antony N. (University of Delaware, Chemical and Biomolecular Engineering)
  5. Mackay, Michael E. (University of Delaware, Materials Science & Chemical and Biomolecular Engineering)

Author and Affiliation Lines (in printed abstract book)
Jeffrey S. Horner1, David D. Phan1, Keith Coasey2, Antony N. Beris1, and Michael E. Mackay2
1Chemical and Biomolecular Engineering, University of Delaware, Newark, DE; 2Materials Science and Engineering, University of Delaware, Newark, DE

Speaker / Presenter 
Mackay, Michael E.

Text of Abstract
Material Extrusion (ME, sometimes called Fused Filament Fabrication (FFF) or Fused Deposition Modeling® (FDM)) is an additive manufacturing technology where a solid fiber of polymer (ca. 1-3 mm in diameter) is driven into a cylindrical, heated sleeve whereupon it melts. The molten polymer seals around the solid fiber, so, it acts as a piston driving itself through a conical nozzle. The pressurized melt is pushed through the orifice to make a filament (ca. 0.5 mm in diameter) that is deposited onto a moving substrate to make an object. We simulate the melting and flow processes using a finite volume technique to find both are complicated. Complex flow patterns develop within the heated sleeve until the fiber is completely melted then non-Newtonian effects come to bear as the melt enters the converging nozzle. A technique was developed to measure the pressure in the nozzle and it is compared to the predicted pressure to find they are adequately correlated. Future research will center on optimizing the heated sleeve and nozzle to allow faster processing and to incorporate viscoelastic effects using the finite element simulation technique that are particularly important in the nozzle.