Work

Fused granulate fabrication of short glass fiber-reinforced PA6: Influence of printing parameters on mechanical performance, porosity, and fiber alignment

Year: 2025

Type: article

Abstract: Additive manufacturing (AM) via material extrusion (MEX), particularly fused granulate fabrication (FGF), expands material options for 3D printing. FGF’s screw-based extrusion allows direct processing of highly filled composite pellets, commonly used in injection molding. This study investigates the engineering composite polyamide 6 with 30 wt.% short glass fibers (PA6GF30) using FGF. A full factorial design of experiments (DOE) was employed to analyze the influence of nozzle diameter, bead ratio (layer height/nozzle diameter), and printing velocity on volumetric flow and its effects on mechanical properties, porosity, and fiber alignment. Statistical evaluation showed that reduced volumetric flow led to increased fiber alignment, lower porosity, and improved mechanical performance. With optimized parameters, the tensile modulus reached 9 GPa—just 5% below injection-molded values—while the ultimate tensile strength was 139 MPa. Flexural modulus and strength were 7.3 GPa and 211 MPa, respectively. Compared to fused filament fabrication (FFF) studies with similar fiber contents, FGF-printed PA6GF30 exhibited markedly higher mechanical properties. This demonstrates FGF’s potential as a robust alternative for producing short-fiber-reinforced polymer components with excellent structural performance and complex geometries, using cost-effective industrial-grade materials.

Source: Materials & Design

DOI: 10.1016/j.matdes.2025.115086

Authors: Philip Töllner, Hermann Seitz

Institution: University of Rostock

Language: English

Topic: Additive Manufacturing and 3D Printing Technologies

Subfield: Automotive Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Industry, innovation and infrastructure

Open Access status: gold

Estimated APC paid: $3,650