Session: 03-03-03: Annual Congress-Wide Symposium on Additive Manufacturing III

Paper Number: 172991

In-Situ Mechanical Property Characterization of 3d-Printed Materials Using Fdm and High-Speed Imaging 

Additive manufacturing (AM) continues to transform materials design and fabrication, yet critical barriers remain in mechanical property characterization, particularly for low-cost, recycled, or in-field materials. Traditional testing methods such as tensile or three-point bending tests require expensive, bulky equipment and destructive sample preparation—making them impractical for distributed or resource-constrained environments like home recycling systems or space-based operations. This work addresses those limitations by introducing a novel, in-situ mechanical testing framework compatible with fused deposition modeling (FDM) platforms, enabling real-time monitoring and evaluation of AM materials using only a standard 3D printer and a high-speed camera.

To overcome these limitations, we developed a cost-effective and portable method for characterizing both the elastic and plastic mechanical behavior of AM polymers, including recycled and multi-material feedstocks. Our approach features two integrated testing modes: (1) vibration-based extraction of elastic modulus from resonant frequency measurements of printed cantilever beams, and (2) curvature-based assessment of plastic deformation using residual geometry after loading. Both methods are implemented directly within the 3D printing environment, eliminating the need for external hardware or destructive testing.

We validated the technique across common, recycled, and multi-material AM materials, including PLA, PETG, and PET derived from consumer plastic bottles. The in-situ elastic modulus values show close agreement with results from conventional tensile and bending tests. For plasticity, we captured beam curvature during and after loading, applying a modified Voce hardening model to extract material yield behavior. The results were benchmarked against finite element simulations, confirming the model’s predictive accuracy across beam geometries.

Importantly, the method supports high-throughput testing, as multiple specimens can be printed and characterized simultaneously in a single build run. This drastically improves efficiency and is particularly suited to process–structure–property studies, batch screening of recycled materials, and educational or field-deployable applications. Furthermore, the in-situ approach enables straightforward characterization of multi-material AM feedstocks. By printing and testing samples composed of blends or spatially varying filaments, users can rapidly evaluate the effects of different material proportions or interfacial zones without requiring new tensile tests or access to an Instron system. This capability significantly enhances the usability of the method for iterative design and formulation tuning, particularly in research, prototyping, or circular economy contexts where material composition is frequently adjusted.

To demonstrate the method’s design integration potential, we used in-situ measurements of an unknown recycled material to inform the creation of functionally graded lattice structures, including octet truss and Kelvin foam architectures. By varying only the lattice geometry (e.g., strut thickness and unit cell size), we tailored structural performance for different mechanical demands—ranging from compliant energy-absorbing designs to stiff, load-bearing cores. This demonstrates how real-time material characterization can be directly translated into design-for-AM (DfAM) workflows, even when working with feedstocks of uncertain or variable quality.

This study directly addresses several critical topics identified by the AM community: in-situ experimental characterization, mechanical behavior of AM materials, qualification of recycled and hybrid AM feedstocks, and functional structure–performance integration. Moreover, the platform’s accessibility opens pathways for democratized materials testing, agile design iterations, and even autonomous AM operation in off-Earth settings.

Presenting Author: Xinyi Yang Georgia Institute of Technology

Presenting Author Biography: Graduate Student in Daniel Guggenheim School of Aerospace Engineering, Georgia Institute of Technology

Authors:

Xinyi Yang Georgia Institute of Technology
Xiaochen Li Daniel Guggenheim School of Aerospace Engineering, Georgia Institute of Technology
Chuqi Sun University of Pennsylvania
Christos Athanasiou Daniel Guggenheim School of Aerospace Engineering, Georgia Institute of Technology
Bolei Deng Daniel Guggenheim School of Aerospace Engineering, Georgia Institute of Technology