Utilizing Fused Filament Fabrication for Printing Iron Cores for Electrical Devices

This work details a polyolefin-elastomer-based binder system to prepare fused filament fabrication (FFF) filaments and print cores for coils for electrical engines. The processability, homogeneity, and thermal properties of the polyolefin-elastomer-based filaments are explored. A two-step debinding and sintering process was established for manufacturing dense iron parts. Results indicate the developed filaments possess superior printing and sintering (at 900°C) performance, yielding only 20% weight loss by polymer decomposition and 14 vol.% shrinkage. This indicates that the FFF technique potentially enables printing of innovative electric motor designs. The designed FFF filaments could be loaded with 80 wt.% Fe powder while keeping a decent melt-viscosity for the printing process. Due to the high metal loading, dense iron parts could be sintered without bending or deformation.