TY - JOUR
T1 - Comparative analysis of binder systems in copper feedstocks for metal extrusion additive manufacturing and metal injection moulding
AU - Sadaf, Mahrukh
AU - Cano Cano, Santiago
AU - Bragaglia, Mario
AU - Schuschnigg, Stephan
AU - Kukla, Christian
AU - Holzer, Clemens
AU - Vály, Lilla
AU - Kukla, Christian
AU - Kitzmantel, Michael
AU - Nanni, Francesca
AU - Gonzalez-Gutierrez, Joamin
N1 - Publisher Copyright: © 2024 The Authors
PY - 2024/2/21
Y1 - 2024/2/21
N2 - In the realm of material innovation, the remarkable versatility of thermoplastic-based highly filled composites emerges as a pivotal advantage for fabricating metal parts, seamlessly integrating design flexibility. This study delves into the fusion of design and manufacturing, spotlighting the convergence of material extrusion additive manufacturing (MEX) and metal injection moulding (MIM) processes through the adept utilization of three distinct in-house developed copper-feedstocks. Each feedstock had a different composition that influenced their processability; two feedstocks were for solvent and thermal debinding, and one was only for thermal debinding. The sintering was carried out under the same conditions for all produced specimens to assess the effect of binder composition on the properties of the sintered components. Structural integrity evaluations of sintered specimens encompassed 3-point bending, hardness tests, and metallography. It was possible to perform MEX with all produced filaments and MIM with the pellets of the same feedstocks and to obtain acceptable-quality specimens. Regardless of the shaping method, specimens shaped with binders containing a soluble binder survived the thermal and sintering steps. The specimens produced from the feedstock intended solely for thermal debinding experienced a nearly complete loss of shape during the debinding process. For the specimens that could be debound and sintered without defects, a relative density between ∼88 and 94 % was measured for MEX components and ∼93 and 95 % for MIM components after sintering. All sintered components showed the same diffraction peaks as pure copper powder, confirming that the reductive hydrogen atmosphere provided protection from contamination and reduced the oxides that could have appeared during thermal debinding in air. Moreover, adequate shrinkage of ∼10–18 % was observed in the sintered specimens. Vickers microhardness of the MEX and MIM sintered components were ∼32 HV and ∼36 HV, respectively. Compared to MEX, MIM-produced sintered components showed a higher maximum stress (i.e., σmax = 79 ± 3.2 MPa). These results demonstrate that the binder composition plays a crucial role in determining the success of metal MEX and MIM processes. Having the possibility to choose between MEX and MIM allows for greater design flexibility for copper parts.
AB - In the realm of material innovation, the remarkable versatility of thermoplastic-based highly filled composites emerges as a pivotal advantage for fabricating metal parts, seamlessly integrating design flexibility. This study delves into the fusion of design and manufacturing, spotlighting the convergence of material extrusion additive manufacturing (MEX) and metal injection moulding (MIM) processes through the adept utilization of three distinct in-house developed copper-feedstocks. Each feedstock had a different composition that influenced their processability; two feedstocks were for solvent and thermal debinding, and one was only for thermal debinding. The sintering was carried out under the same conditions for all produced specimens to assess the effect of binder composition on the properties of the sintered components. Structural integrity evaluations of sintered specimens encompassed 3-point bending, hardness tests, and metallography. It was possible to perform MEX with all produced filaments and MIM with the pellets of the same feedstocks and to obtain acceptable-quality specimens. Regardless of the shaping method, specimens shaped with binders containing a soluble binder survived the thermal and sintering steps. The specimens produced from the feedstock intended solely for thermal debinding experienced a nearly complete loss of shape during the debinding process. For the specimens that could be debound and sintered without defects, a relative density between ∼88 and 94 % was measured for MEX components and ∼93 and 95 % for MIM components after sintering. All sintered components showed the same diffraction peaks as pure copper powder, confirming that the reductive hydrogen atmosphere provided protection from contamination and reduced the oxides that could have appeared during thermal debinding in air. Moreover, adequate shrinkage of ∼10–18 % was observed in the sintered specimens. Vickers microhardness of the MEX and MIM sintered components were ∼32 HV and ∼36 HV, respectively. Compared to MEX, MIM-produced sintered components showed a higher maximum stress (i.e., σmax = 79 ± 3.2 MPa). These results demonstrate that the binder composition plays a crucial role in determining the success of metal MEX and MIM processes. Having the possibility to choose between MEX and MIM allows for greater design flexibility for copper parts.
KW - Additive manufacturing
KW - Copper
KW - Debinding
KW - Material extrusion (MEX)
KW - Metal injection moulding (MIM)
KW - Sintering
KW - Feedstock
KW - Copper
KW - Polymer processing
KW - Material Extrusion
KW - Additive Manufacturing
UR - http://www.scopus.com/inward/record.url?scp=85186267664&partnerID=8YFLogxK
U2 - 10.1016/j.jmrt.2024.02.163
DO - 10.1016/j.jmrt.2024.02.163
M3 - Article
AN - SCOPUS:85186267664
SN - 2238-7854
VL - 29.2024
SP - 4433
EP - 4444
JO - Journal of Materials Research and Technology
JF - Journal of Materials Research and Technology
IS - March-April
ER -