Experimental and Numerical Investigation of the Interfacial Bonding in Multi-Material Fused-Filament Fabrication Using Mode-I Fracture Toughness
- 1Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261, Saudi Arabia
- 2Interdisciplinary Research Center for Biosystems and Machines, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261, Saudi Arabia
Abstract
Multi-material fused-filament fabrication (FFF) enables the integration of two or more materials within a single printed component, offering significant potential for producing functionally graded and hybrid structures with tailored mechanical properties. However, the effects of processing conditions on interfacial quality and fracture behavior in multi-material FFF remain insufficiently understood. This study investigates the Mode-I interfacial fracture behavior of multi-material FFF using compact-tension (CT) specimens through combined experimental testing and finite-element simulation. CT specimens were fabricated from polylactic acid (PLA), thermoplastic polyurethane (TPU), and polyethylene terephthalate glycol (PETG) using five raster configurations, including rectilinear 0°/90°, ±45° and aligned-rectilinear 0°, 45°, 90° configurations. The load-extension response, peak load (Pmax), critical stress-intensity factor (KIC), and critical strain-energy release rate (GIC) were evaluated. Two-way ANOVA showed that material pairing was the dominant statistically significant factor affecting peak load, whereas raster orientation and its interaction with material pairing were not statistically significant. The PETG–TPU interface exhibited the highest fracture resistance, with the AR-45 orientation producing an average Pmax of 130.90 N, KIC of 0.761 MPam, and GIC of 375.5 N/m. Fracture-surface observations supported these findings, revealing greater deformation, material transfer, surface roughness, and mechanical interlocking in the PETG–TPU specimens. The calibrated cohesive-zone model demonstrated the stress contours and the localized interfacial damage patterns. Overall, material pairing primarily governed interfacial fracture resistance, whereas raster orientation showed no statistically significant effect under the tested conditions.
Related
- Numerical and experimental study on the fabrication of core-shell fibers for tissue engineering using a microfluidic-electrospinning coupled method
- Experimental and Numerical Investigation of End-Tab Geometry Effects on the Compressive Response of Ultra-Thick CFRP Laminates
- Experimental and numerical investigation of accelerated carbonation of recycled fines
- Mechanical Performance of Bio-Based Additively Manufactured Honeycomb Sandwich Panels: Experimental and Numerical Investigation
- Experimental and Numerical Investigation of Orthotropic CFR-PEEK and Ti-6Al-4V Osteosynthesis Plates Using a Multiscale Finite Element Modeling Approach
BibTeX
@article{fenta2026experimental,
title = {{Experimental and Numerical Investigation of the Interfacial Bonding in Multi-Material Fused-Filament Fabrication Using Mode-I Fracture Toughness}},
author = {Ermias Wubete Fenta and Mohd Tauheed and Sarfaraz Ahmed Furquan and Ammar Alsheghri},
journal = {Polymers},
year = {2026},
month = oct,
doi = {10.3390/polym18202529},
url = {https://www.mdpi.com/2073-4360/18/20/2529},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Experimental and Numerical Investigation of the Interfacial Bonding in Multi-Material Fused-Filament Fabrication Using Mode-I Fracture Toughness
AU - Ermias Wubete Fenta
AU - Mohd Tauheed
AU - Sarfaraz Ahmed Furquan
AU - Ammar Alsheghri
PY - 2026
DA - 2026/10/01
JO - Polymers
DO - 10.3390/polym18202529
UR - https://www.mdpi.com/2073-4360/18/20/2529
AB - Multi-material fused-filament fabrication (FFF) enables the integration of two or more materials within a single printed component, offering significant potential for producing functionally graded and hybrid structures with tailored mechanical properties. However, the effects of processing conditions on interfacial quality and fracture behavior in multi-material FFF remain insufficiently understood. This study investigates the Mode-I interfacial fracture behavior of multi-material FFF using compact-tension (CT) specimens through combined experimental testing and finite-element simulation. CT specimens were fabricated from polylactic acid (PLA), thermoplastic polyurethane (TPU), and polyethylene terephthalate glycol (PETG) using five raster configurations, including rectilinear 0°/90°, ±45° and aligned-rectilinear 0°, 45°, 90° configurations. The load-extension response, peak load (Pmax), critical stress-intensity factor (KIC), and critical strain-energy release rate (GIC) were evaluated. Two-way ANOVA showed that material pairing was the dominant statistically significant factor affecting peak load, whereas raster orientation and its interaction with material pairing were not statistically significant. The PETG–TPU interface exhibited the highest fracture resistance, with the AR-45 orientation producing an average Pmax of 130.90 N, KIC of 0.761 MPam, and GIC of 375.5 N/m. Fracture-surface observations supported these findings, revealing greater deformation, material transfer, surface roughness, and mechanical interlocking in the PETG–TPU specimens. The calibrated cohesive-zone model demonstrated the stress contours and the localized interfacial damage patterns. Overall, material pairing primarily governed interfacial fracture resistance, whereas raster orientation showed no statistically significant effect under the tested conditions.
SN - 2073-4360
ER -