Approach for Mechanical Isotropic Material Extrusion Printing

Abstract

This paper presents a novel approach to mitigate anisotropic material behavior
in material extrusion (MEX) components, using fused granulate modeling (FGM) as
fabrication technique and standard injection molding feedstock as material. This method,
further named as Voxelfill disrupts the conventional layer-by-layer deposition by
introducing a volumetric chamber filling technique and therefore aims to achieve isotropic
properties in additive manufacturing (AM). This applies for both unfilled and fiber
reinforced thermoplastic polymers. The initial section of the paper articulates the
motivation behind this study, providing an overview of the challenges posed by anisotropy
in MEX processes. Following this, the Voxelfill process is briefly analyzed, with insights on
its integration into slicing software and the hardware modifications necessary for
implementation.The core focus of this study is to assess the mechanical performance of 30
% glass fiber-reinforced PETG parts by fabricating tensile test samples using the Voxelfill
process and comparing them with specimens produced through conventional layer-by
layer printing. Results demonstrate that the Voxelfill process reduces anisotropy from
56.71 % to 13.47 %. These findings underscore the potential of the Voxelfill process to
substantially mitigate anisotropic behavior in MEX components.The paper concludes with
a discussion on future directions to further optimize and validate the benefits of the Voxelfill
process, paving the way for enhanced reproducibility and performance in additive
manufacturing applications.