Influence of Binder Composition and Material Extrusion (MEX) Parameters on the 3D Printing of Highly Filled Copper Feedstocks

Research output: Contribution to journalArticleResearchpeer-review

Authors

  • Mahrukh Sadaf
  • Joamin Gonzalez-Gutierrez
  • Mario Bragaglia
  • Lilla Vály
  • Michael Kitzmantel
  • Franesca Nanni

External Organisational units

  • University of Rome “Tor Vergata”
  • RHP Technology GmbH
  • University of Ljubljana

Abstract

This work aims to better understand the type of thermoplastic binders required to produce highly loaded copper filaments that can be successfully printed via low-cost filament-based material extrusion (MEX). Compounding feedstock material with 55 vol.% of copper and three multi-component binder systems has been performed. The MEX behavior of these feedstocks was evaluated by depositing material at different speeds and appropriately selecting the extrusion temperature depending on the binder composition. The rest of the MEX parameters remained constant to evaluate the printing quality for the different feedstocks. Printable filaments were produced with low ovality and good surface quality. The filaments showed good dispersion of the powder and polymeric binder system in SEM analysis. The feedstock mechanical properties, i.e., the tensile strength of the filament, were sufficient to ensure proper feeding in the MEX machine. The viscosity of the feedstock systems at the adjusted printing temperatures lies in the range of 102–103 Pa·s at the shear rate of 100–1000 s−1, which appears to be sufficient to guarantee the correct flowability and continuous extrusion. The tensile properties vary greatly (e.g., ultimate tensile strength 3–9.8 MPa, elongation at break 1.5–40.5%), and the most fragile filament could not be reliably printed at higher speeds. Micrographs of the cross-section of printed parts revealed that as the printing speed increased, the porosity was minimized because the volumetric flow of the feedstock material increased, which can help to fill pores. This study offers new insights into the feedstock requirements needed to produce low-cost intricate copper components of high quality in a reliable and efficient manner. Such components can find many applications in the electronics, biomedical, and many other industries.

Details

Translated title of the contributionEinfluss der Binderzusammensetzung und Material Extrusions (MEX) Parameter auf 3D drucke von hochgefüllten Kupferfeedstocks
Original languageEnglish
Article number4962
Number of pages23
JournalPolymers / Molecular Diversity Preservation International
Volume14.2022
Issue number22
DOIs
Publication statusPublished - 16 Nov 2022