Radiopaque filaments for fused filament fabrication (FFF) 3D printing
Bibliographic record
Abstract
Polyetheretherketone (PEEK) is a chemically resistant, high-performance polymer known for its excellent thermal and mechanical properties. It is increasingly employed in the development of 3D-printed medical implants and radiotherapeutic devices. While PEEK exhibits strong resistance to radiation-induced degradation, it has inherently poor radiation-blocking capacity. However, many tools and components used in radiology, radiotherapy, and nuclear medicine—such as brachytherapy implants, shielding devices, imaging screens, and personalized radioprotective equipment—require a certain degree of radiopacity. This study presents a novel methodology for integrating electron-dense particles (micro- or nano-sized) into high-performance polymer filaments suitable for fused filament fabrication (FFF) 3D printing. Specifically, a new pre-processing approach was developed to achieve optimal mixing of micrometer-sized tungsten (µW) particles with micrometer-sized PEEK particles (µPEEK), prior to their incorporation into millimeter-sized PEEK pellets. This tri-phased particle mixture enabled high-temperature extrusion, producing robust, continuous filaments with uniformly embedded metal particles within a protective polymer matrix. The resulting filaments were characterized using scanning electron microscopy (SEM) to assess morphology, X-ray fluorescence (XRF) imaging to evaluate particle distribution homogeneity, and elemental analysis to quantify the content of the radiation-blocking material. Filaments containing tungsten at concentrations below 10 vol.% were used to fabricate high-density, 3D-printed structures of varying thicknesses. Optimal printing parameters were identified, and the X-ray attenuation properties of the printed objects were evaluated through radiographic imaging. Additionally, mechanical properties of the 3D printed PEEK, and PEEK-W composites were evaluated through standardized flexural and Vickers hardness testing. Finally, biocompatibility testing using primary human choroid fibroblast (hCSF) cells demonstrated high cell viability after four days of exposure to the W-loaded PEEK prints. These findings highlight the potential of 3D-printed radiopaque polymers not only for medical implants but also for applications in aerospace and nuclear technology.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 0.002 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".