Feedstock Development for Material Extrusion-Based Printing of Ti6Al4V Parts

Abstract

In this work, a holistic approach for the fabrication of dense Ti6Al4V parts via material extrusion methods (MEX), such as fused filament fabrication (FFF) or fused feedstock deposition (FFD), will be presented. With respect to the requirements of the printing process, a comprehensive investigation of the feedstock development will be described. This covers mainly the amount ratio variation of the main binder components LDPE (low-density polyethylene), HDPE (high-density polyethylene), and wax, characterized by shear and oscillation rheology. Solid content of 60 vol% allowed the 3D printing of even more complex small parts in a reproducible manner. In some cases, the pellet-based FFD seems to be superior to the established FFF. After sintering, a density of 96.6% of theory could be achieved, an additional hot isostatic pressing delivered density values better than 99% of theory. The requirements (mechanical properties, carbon, and oxygen content) for the usage of medical implants (following ASTM F2885-17) were partially fulfilled or shortly missed.

3D Printing of Na1.3Al0.3Ti1.7(PO4)3 Solid Electrolyte via Fused Filament Fabrication for All‐Solid‐State Sodium‐Ion Batteries

“…27 Nm, due to increased particle‐particle interactions of the powder material. As the wetting of powder and binder material increases, the torque decreases (kneading zone) and reaches an equilibrium region at which a homogeneous distribution of the powder in the binder can be assumed (equilibrium zone) [23] . Measured final torque values for (55, 58 and 60) vol % feedstocks are (6.9, 8.6 and 9.6) Nm, respectively.…”

“…As the wetting of powder and binder material increases, the torque decreases (kneading zone) and reaches an equilibrium region at which a homogeneous distribution of the powder in the binder can be assumed (equilibrium zone). [23] Measured final torque values for (55, 58 , c) extruded filament fracture surface (58 vol %) and winded filament spool as inset, d) 3D printed specimen fracture surface of liquid nitrogen cooled 3D printed green part (58 vol %), e) higher magnification of 3D printed specimen fracture surface, f) solvent debinding of 58 vol % filled feedstock at room temperature over debinding time.…”