Simulations Of The Filament Printing Of Metal Feedstocks With Different Nozzle Designs

Authors

Kukla C., Schuschnigg S., Hubmann M., Cano S., Hentschel L., Gonzalez-Gutierrez J., Holzer C.

Reference

World PM 2022 Congress Proceedings, 2022

Description

Material extrusion (MEX), specially fused filament fabrication (FFF), is the most widespread technology for additive manufacturing, mainly for polymers. MEX can also be used as part of the fabrication process to obtain metal specimens when metal-filled polymer feedstocks are used. Currently, many MEX printers and nozzle designs are available from different manufacturers. These different nozzle designs result in different melting and flow behaviour. Therefore, their design is critical for the printing of high-quality parts. Since feedstocks and polymers have different characteristics, we evaluated the processing of an Ampersint 1558 tool steel feedstock with two different nozzle designs (nozzle with a PTFE tube insert and a full metal nozzle) using finite element method (FEM) simulations with the program Ansys Polyflow®. Feedstock's rheological and thermal properties were measured and used for the FFF simulation with the two nozzle designs at different printing speeds. Finally, the trends observed in the simulations were compared to experimental results, providing recommendations for the design of FFF nozzles for feedstocks.