Additive manufacturing

The healthcare sector is undergoing a transformative revolution through the widespread adoption of 3D-printing technologies, as evidenced by a wealth of applications already available in the literature. These innovations have opened up new design possibilities and paved the way for personalized solutions that enhance the care of patients and healthcare professionals. This chapter explores the current and potential contributions of 3D printing to healthcare, examining diverse solutions and strategies facilitated by the continuous technological advancements in additive manufacturing. A hypothetical patient's journey is envisioned to contextualize the benefits patients and healthcare practitioners can derive from 3D-printed interventions. Additionally, this chapter contemplates unresolved challenges in integrating 3D printing into healthcare, such as the need for robust design and manufacturing procedures, essential competencies and roles, and the economic feasibility of these solutions. These questions serve as catalysts for further investigation and discussion. © 2025 Elsevier Inc.

Keywords: 3D printing , biomedical engineering , care , design for additive manufacturing , drug development , in situ printing , patient journey , personalized medicine , regenerative medicine , robotic-assisted 3D printing

Binder Jetting (BJT) is a promising, yet scarcely explored, additive manufacturing technology suitable for the production of orthopedic surgical instruments, offering design flexibility, material versatility, and cost-effectiveness compared to traditional subtractive manufacturing. This study assesses the feasibility of metal BJT for manufacturing surgical instruments used in knee and hip arthroplasty. Given the limited availability of literature data about such a technology, a preliminary evaluation of sample density, mechanical properties, and dimensional accuracy was performed, taking into account the main geometrical features characterizing surgical instruments. The results demonstrate that BJT enables the fabrication of lightweight and complex geometries while achieving satisfying mechanical properties. Thin walls (0.2 mm), small holes (0.5 mm), and cylindrical extrusions (0.7 mm) were successfully printed, providing insights into BJT resolution limits. However, shrinkage during sintering was a significant challenge, requiring tailored sintering supports and counter-deformation strategies for dimensional and geometrical accuracy. The application of linear scaling factors partially mitigated anisotropic shrinkage, with deviations up to 0.44 mm for prismatic samples. Mechanical properties varied with the z-level in the print chamber, limiting the repeatability of components' performance within the printing volume. In addition, lightweight designs for surgical instruments, such as trial acetabular cups and femoral stems, were successfully manufactured, achieving significant weight reduction while maintaining functional performance. The study identifies critical Design for Additive Manufacturing (DfAM) guidelines for metal BJT, emphasizing strategies to address sintering distortions. Despite challenges, BJT shows strong potential for producing customizable and lightweight surgical instruments, paving the way for its broader adoption in biomedical manufacturing.

Keywords: Design for Additive Manufacturing , Medical devices , Metal Binder Jetting , Printing resolution , Surgical instruments

The rapid diffusion of additive manufacturing (AM) raises the need to carefully evaluate its environmental sustainability. However, the continuous evolution of AM technologies makes life cycle assessment (LCA) studies, which consider traditional technologies, of little significance. The problem is accentuated if one wants to consider such studies to make decisions in the manufacturing sector for the near future. To overcome this limitation, this study considers patented AM technologies related to Direct Energy Deposition (DED) and employs prospective LCA methodology to estimate its future impacts. This approach holds the potential to provide valuable insights into the future of these technologies, particularly when they reach technological maturity and large-scale production. The peculiarity of this study lies in the use of patents as a source to extract the data that are used to model the foreground inventory of future DED. Consistently with the time scope of the analysis, the background inventory is also modelled in future time, modifying the production impacts of materials and energy using Integrated assessment modelling. The environmental impact of future DED is estimated by considering foreground data and background inventory. The results are compared with the DED impacts available on the market today to identify the main environmental benefits that patents can bring. The collection and analysis of the technological solutions claimed in the same patents and their classification according to the environmental advantages is used to identify eco-design solutions and strategies that can be considered to improve the sustainability of current DED technology.

Keywords: additive manufacturing , patent analysis , prospective LCA

Lattice are porous structures obtained by a controlled repetition in the space of a designed unit cell, resulting in reduced weight and unique functional characteristics such as high specific strength and stiffness, mechanical energy absorption, and heat transfer control. This work aims to tailor geometrical variables and process parameters to fabricate L-PBF Inconel 718 beam-based lattice structures, focusing on their novel use as support structures during the printing process of metallic components, enhancing structural integrity and heat dissipation. 3D models of different porous structures (cell type: FCC-Z) were developed varying geometrical parameters. Finite Element Method simulations were conducted by Ansys, validating its ability to meet quality standards for directional deformations and residual stresses. The simulation's correlation with the coordinate measuring machine (CMM) analysis confirmed the accuracy of the model. Scanning electron microscopy (SEM) characterization was employed to analyze the deformation and failure characteristics of the lattices, excluding those with geometric parameters unsuitable for optimal support performance. Microstructural analysis revealed partial recrystallization in the heat-treated samples. The remaining dendritic structures indicate incomplete homogenization, particularly near the lattice. Precipitated strengthening phases such as γ′ and δ were identified, alongside minor quantities of η phases and MC carbides, which could influence ductility and strength. Vickers microhardness tests showed higher hardness in the heat-treated samples, particularly at nodes and struts, with a more uniform hardness distribution in heat-treated samples due to the precipitation of strengthening phases. This highlights the role of heat treatment in enhancing the material's mechanical properties.

Keywords: Characterization , Finite element method analysis , Inconel 718 , L-PBF , Lattice structures

In recent years the demand of components with low weight and high mechanical properties in terms of strength and stiffness has rapidly increased. In this scenario, lattice structures can provide a compelling alternative with respect to the classical bulk components. In this study, the elastic–plastic behaviour of face centred cubic unit cell with vertical strut (F2CCZ) manufactured through laser powder bed fusion (LPBF) and made of AlSi10Mg, was explored. Standard bulk unnotched specimens were initially produced and tensile tests were performed to investigate the elastic–plastic behaviour of the material. The obtained results were used to perform, through finite element (FE), elastic–plastic homogenization of the representative volume elements (RVEs) with nominal geometry and by using periodic boundary conditions (PBCs). A novel simplified approach combining Hill yielding criterion, Levy-Mises plastic flow rule and a reference plastic curve was proposed to describe the different hardening of RVEs in the various directions. Simplified mathematical expressions were proposed and validated to characterize, for the first time, the dependence of elastic–plastic homogenized properties on the aspect ratio (AR). After that, novel graded lattice specimens, with the aim of localizing the failure in the centre of the specimen, were designed and tensile tests were performed with digital image correlation (DIC) for strain measurements. The scanning electron microscope (SEM) was used to investigate the differences between as-built and as-designed strut diameters, and the obtained results were employed to perform FE simulations.

Keywords: AlSi10Mg , Anisotropic hardening behaviour , Digital image correlation , F2CCZ cell , Homogenization , Scaling operation

Lattice structures are increasingly employed in lightweight, high-performance applications, where additive manufacturing allows precise tailoring of their mechanical response. However, tensile testing remains difficult due to complex geometry, anisotropy, and gripping challenges that often induce stress concentrations and premature failure. This work introduces an optimization-driven framework for the design and standardization of tensile lattice specimens, relying on a reduced-order finite element model based on compensated beam theory. The framework integrates a novel merit index based on average strain energy density to reduce mesh dependency, enabling robust and efficient two-step optimization, acting on the material distribution in the transition region and base geometry design. The optimized design ensures smooth stress transfer and minimizes localized effects. To validate the approach, a case study is conducted on a BCC lattice specimen fabricated via Multi-Jet Fusion (MJF). Experimental results in the elastic regime show less than 5 % deviation from numerical predictions, confirming the method's reliability.

Keywords: Compensated beam modeling , Gradient-based optimization , Lattice tensile specimens , Mechanical metamaterials , Multi-Jet fusion additive manufacturing

This study extends previous research on the mechanical properties of FDM-printed PLA parts by analyzing StoneFilTM Granite (SFG) (PLA with 50% stone powder) and WoodFill (WF) (PLA with 30% wooden fibers). The aim is to compare how printing parameters influence the mechanical characteristics of these materials versus conventional PLA, providing insights for biomechanical applications. Understanding these effects is crucial for optimizing 3D-printed devices' performance. A total of 36 parameter combinations, defined by a previous literature review, were used to print test specimens of the selected materials. Tensile, compression and bending tests were followed by ISO 5893:2019 standards to calculate stiffness and elastic modulus. Significant variations in the mechanical properties of SFG and WF were observed based on different printing parameters, consistent with previous PLA findings [Mencarelli M, Sisella M, Puggelli L, Innocenti B and Volpe Y, Sensitivity analysis of 3D printing parameters on mechanical properties of fused deposition modeling-printed polylactic acid parts, Appl Mech 6(1):17, 2025]. Analysis showed that infill pattern, density, orientation and the number of outer shells had variable effects on mechanical performance across all materials. Trends in the influence of manufacturing parameters on mechanical properties were consistent across the materials. This suggests that these trends can apply to other PLA-based composite filaments, enhancing understanding and optimization of 3D-printing processes with new composite filaments for applications requiring precise control over mechanical characteristics.

Keywords: 3D printing settings , FDM , mechanical properties , PLA , stoneFilTM granite , woodfill

Alumina is a technical ceramic that finds several industrial applications due to its favorable mechanical, electrical, and chemical properties. For these reasons, it is often used as an electric insulator, a refractory material, and for wear-resistant components. Nevertheless, due to its hardness, alumina is hardly machinable, and conventional manufacturing technologies do not allow to create components that are characterized by complex shapes. Fortunately, the advent of 3D printing technologies gives the possibility to produce complex-shaped components made of technical ceramics at low cost and time-efficiently. One such technology is Fused Filament Fabrication, a material extrusion additive manufacturing technology initially developed for polymers but adapted to create metal and ceramic components as well. In this process, the printing parameters play a fundamental role since they can significantly impact the final density and the occurrence of internal defects of the sintered part. This paper presents the results of an experimental campaign conducted to assess the best printing parameters in terms of flow and printing temperature. To this mean, the statistical approach of the Design of Experiments was used, aiming to correlate the printing variables with relative density and flexural strength. The former achieved values as high as 99%, whereas the latter, measured by a 3-point bending test, reached up to 433 MPa.

Keywords: Additive manufacturing , Alumina , Ceramic , Debinding , Fused filament fabrication , Material extrusion , Printing parameters , Sintering

Selective laser melting (SLM) allows powder reuse in consecutive cycles, a cost-effective and sustainable practice. However, repeated reuse can degrade powder quality, impacting the final product's mechanical properties. This study presents a methodology combining Failure Mode and Effect Analysis (FMEA) with the Theory of Inventive Problem Solving (TRIZ) to address issues in reusing Ti6AL4V powder in SLM. The approach identifies and mitigates potential failures while leveraging an AI-based chatbot to expedite solution-finding. A case study is implemented to demonstrate the FMEA-TRIZ approach proposed in this paper, showcasing the potential benefits of this innovative methodology.

Keywords: FMEA , generative AI , powder degradation , reused powde , Ti6AL4V , TRIZ

Featured Application: Negative-stiffness lattice structures represent a groundbreaking class of mechanical metamaterials capable of redistributing pressure in highly efficient and adaptive ways. Thanks to their unique ability to undergo localized deformation while maintaining global structural integrity, these lattices are ideal for applications requiring uniform load distribution, energy absorption, and enhanced comfort. From biomedical implants to aerospace panels and protective equipment, their tunable mechanical response opens new frontiers in design and performance. Diabetes mellitus often leads to peripheral neuropathy that compromises protective sensation in the feet and raises ulcer risk through mechanical overload. While prior research has introduced cellular-metamaterial-based shoe midsoles for dynamic plantar pressure redistribution, this study advances the field by delivering a complete, application-oriented workflow for physical prototyping and mechanical validation of such structures. Our pipeline integrates analytical synthesis of curved-beam unit cells, process calibration, and fabrication via thermoplastic polyurethane (TPU) fused-filament fabrication, producing customized, test-ready lattices suitable for future gait-simulation studies and in vivo assessment. Printed TPU tests showed a Young's modulus of 44.5 MPa, ultimate tensile strength of 4.9 MPa, and strain at break ≈ 20% (Shore 84.5 A/37.2 D). The cellular unit's compressive response was quantified by theoretical force-threshold estimates and controlled compression tests, enabling data-driven selection of unit cell geometry and arrangement for effective offloading. The response is rate-dependent: higher loading speed increases peak force and hysteresis, indicating that loading rate should be treated as a design parameter to tune dynamic behavior for the target application. Although the analytical model overestimates forces by roughly 50% on average relative to experiments, it accurately captures the influence of key geometric parameters on peak force. Accordingly, experimental data can identify cell strategic geometric parameters (i.e., Q), while the achievable maximum force can be predicted from the model by applying an appropriate correction factor.

Keywords: diabetes mellitus , lattice structures , midsoles , negative stiffness , thermoplastic polyurethane (TPU)

Porous media have been demonstrated to be efficient heat transfer surfaces but they must be optimized for any given applications. In this regard, numerical simulations can improve the analyses of heat transfer and fluid flow in porous media, making their design and optimization faster, cheaper, and more reliable. Unfortunately, implementing detailed numerical simulations of stochastic foams is challenging because the geometry of a commercially available foam is usually randomly generated and must be reconstructed with cumbersome and expensive methods, like X-ray tomography. Vice versa, the use of a perfectly known geometry can be very helpful for improving the reliability, consistency and robustness of the numerical analyses. This work demonstrates that it is possible to design from scratch a stochastic open-cell foam using computational geometry algorithms and fabricate it by additive manufacturing. In fact, in the present study, a foam was designed and 3D printed, before being tested and numerically analyzed. When tested, the designed foam performed exactly the same as compared to traditional foam but being the geometry completely known, it was possible to run a direct simulation, opening, for the first time, the opportunity to optimize the thermo-fluid behavior of the porous media. After model validation, foams with the same porosity but different pore density were then numerically simulated, monitoring the corresponding pressure drops.

Keywords: Additive manufacturing , Cellular solids , Experimental test , Foam numerical simulation , Lattice structures , Open-cell foam , Pressure drop

Featured Application: The work finds potential application in the design and manufacture of patient-specific scaffolds in the biomedical field using desktop MEX AM technologies. The design of scaffolds and prostheses benefits from the opportunities provided by additive manufacturing technologies. Specifically, scaffold design using cellular structures based on lattices has become a significant focus. These lattice-based scaffolds exhibit intricate and complex shapes with controlled macro-porosity. In this study, a method is presented that enables the modeling of a graded-density lattice structure for material extrusion additive manufacturing, without relying on a geometric lattice model. The methodology utilizes computed tomography (CT) scans as inputs to obtaining a 3D scalar field and a surface model. The lattice structure is designed and generated within the computer-aided manufacturing (CAM) software, ensuring consistent machine toolpaths. The 3D scalar field, representing a relative density map derived from CT Hounsfield units, drives the variation of the extrusion parameters generated by the CAM, achieving a graded-density lattice.

Keywords: additive manufacturing , computed tomography , functionally graded lattice structures , fused filament fabrication , graded lattices , volumetric modeling

The production of titanium (Ti6Al4V) powder is critical for aerospace, biomedical, and additive manufacturing but poses environmental challenges due to its energy intensity. Existing assessments often rely on static LCAs, offering limited optimization, or employ fragmented parametric models that do not capture full system interdependencies. This study introduces a novel, comprehensive parametric Life Cycle Assessment (LCA) framework for Ti6Al4V powder production, addressing these limitations. Its core methodological innovation lies in the integration of the entire production chain (from mining to sieving) and the simultaneous optimization of technically crucial, interdependent operational parameters, specifically, TiO2 content in slag (typically 0.78–0.90), atomization electrode diameter (0.04–0.10 m), and argon pressure (often ≈5.5 MPa), rather than just parameterizing mass/energy flows as often seen in prior models. This is achieved by linking upstream process quality (e.g., slag composition impacting chlorination energy) to downstream performance and environmental impacts (e.g., atomization energy and waste generation) through empirically-derived relationships based on extensive literature data. The model minimizes environmental impact under user-defined control conditions (target powder diameter, region, impact category). Numerical investigation demonstrates significant impact reduction potential. Crucially, the model quantifies environmental trade-offs between conflicting objectives and reveals critical hotspots, with atomization and chlorination consistently accounting for >70 % of impacts even post-optimization. Energy consumption sensitivity is high, varying over five-fold for key steps based on parameter adjustments.

Keywords: Constraint non-linear programming , Optimization model , Parametric LCA , Ti6Al4V powder production

The demand for lightweight yet mechanically robust components has driven the exploration of lattice structures, which offer superior weight-to-strength ratios compared to traditional bulk materials. This study investigates the elastic–plastic behaviour of Polyamide 12 (PA12) lattice structures manufactured via multi jet fusion (MJF). The research combines experimental, numerical, and theoretical approaches to develop a robust framework for the mechanical homogenization of these structures. Tensile tests were performed on bulk and graded lattice specimens to characterize their constitutive behaviour. A simplified homogenization method, integrating periodic boundary conditions (PBCs) with the Hill yielding criterion and Levy-Mises plastic flow rule, was developed to model the anisotropic plastic response of representative volume elements (RVEs). This framework accounts for direction-dependent hardening, enabling efficient prediction of lattice behaviour under complex loading scenarios. Numerical simulations of homogenized RVEs reflected experimental results with a good level of accuracy, validating the model's ability to capture both elastic and plastic deformation regimes. Findings highlight the potential of the proposed methodology for structural optimization and mechanical performance prediction in applications requiring lightweight and durable materials, such as automotive, aerospace, and biomedical devices.

Keywords: Anisotropic plastic behaviour , Homogenization , Lattice structures , Multi jet fusion , Periodic boundary conditions , Polyamide 12

Lattice structures find extensive use in multiple engineering sectors due to their tailored high specific mechanical properties. These structures are characterised by the repetition of one, or multiple, unit cell(s). Starting from a standard Body-Centered Cubic (BCC) unit cell, this study presents a new numerical approach for modelling lattice structures from the single unit cell. Specifically, a novel 1D numerical model is presented featuring custom-defined area and inertia values for the beam elements of the cell struts, independent of their nominal diameter value. The mechanical properties are evaluated through uniaxial compression and in-plane shear tests. Numerical analyses were carried out using Ansys 2023 R2 implementing a custom Ansys Parametric Design Language (APDL) routine. Subsequently, custom-made and commercial neural networks, trained using 3D finite element method simulations, were used to optimise the user-integrated area and inertia values. By comparing their results is possible the identification of the most suitable parametric values for different strut diameters. The proposed 1D method is aimed at reducing the modelling and computational complexity associated with traditional 3D FEM approaches while retaining the ability to predict mechanical behaviour accurately. By simplifying lattice struts into 1D beam elements, computational costs can be reduced, allowing the analysis of full-scale lattice structures and parametric studies across various designs and loading conditions. The method was validated through comparisons of 3D and 1D numerical simulations and with well established approaches in the literature through a three-point bending test with variable spans.

Keywords: FEM , Lattice Structures , Neural Network

Lattice structures are widely used in several fields such as in the aerospace, biomedical and automotive industries. Among the others, their efficiency in thermal dissipation, the high capability to absorb energy from impacts coupled with improved specific mechanical properties contributed to attract the attention of designers and researchers. Moreover, in the last decade, the development of more efficient additive manufacturing (AM) techniques and the possibility to obtain complex architectures further boosted their employment with remarkable benefits in terms of production costs, material saving and environmental impact. This study introduces a novel modification of the standard body-centred cubic (BCC) lattice, referred to as the waved body-centred cubic (WBCC), which features curvilinear struts. In this work, direct metal laser sintering (DMLS) AM was employed to fabricate WBCC lattice structures. The experimental campaign focused on two types of specimens: compression samples and sandwich flexural specimens. A comparative analysis between WBCC and BCC lattice structures was also carried out by using existing analytical models to highlight the differences in their mechanical response.

Nowadays use of sandwich structures in structural design is increasing, especially in transportation engineering fields, such as aeronautical and automotive. Sandwich structures are characterized by two thin layers (skins) with a thick, but light, core in the middle, for increased stiffness to bending. The improvement of additive manufacturing techniques opens the door to adopting lattice structures, very light and geometrically complex structures based on a repetitive element, as cores of sandwich structures. The advantages offered by these structures are related to the possibility to variate the structural behaviour by changing geometrical factors such as the array configuration, the unit cell shape or topology, and the relative density. The research presented in this paper is aimed at studying low velocity impact behaviour on curved additive manufactured body-centred cubic (BCC) lattice structures. These structures are characterized by a length L of 10 mm and are numerically designed by modifying the core unit cell topology. Starting from a linear configuration, sine-waved struts were introduced along the main diagonals of the cube, with a wavelength of 3L = 17.32 mm and an amplitude of 0.2 L. The curved shape is proposed with two different orientation. Moreover, the aim is to develop hybrid aluminium/composite structural solutions characterized by high energy absorption features for occupants passive safety purposes. Indeed, the components were able to absorb up to 76% of the initial impact energy with an indentation level lower than 3.7 mm. These structures feature low weight, due to a density of 0.715 g/cm3 for the whole component, and occupant protection in transportation.

Keywords: Additive manufacturing , FEM , Impact , Lattice structures , Sandwich structures

Background and Objective: The paper aims to demonstrate the integration of advanced technologies, including computed tomography (CT), computer-aided design (CAD), and additive manufacturing, for precise surgical planning and personalized solutions in the management of Osteogenesis Imperfecta (OI). The main research question is to determine how these technologies can be utilized to achieve successful surgical outcomes in severe cases of OI, such as the one presented in this study. Methods: The study involved an 11-year-old child with OI who suffered from a closed right diaphyseal femur fracture and severe lower extremity abnormalities. Virtual and physical planning procedures were carried out using CAD software based on patient-specific CT models. The length of the proximal and distal segments, cutting planes, and osteotomies were precisely defined to achieve the desired surgical corrections. Additionally, 3D models of the bones and bony segments were manufactured using additive manufacturing to physically recreate the surgical procedure. Results: The surgical treatment involved the correction of the right femur fracture and the left tibia and fibula in the first procedure, followed by the correction of the remaining segments in a second procedure. The Fassier-Duval telescopic intramedullary nail was used to stabilize the fracture and the osteotomy sites. The entire treatment course, from the first surgery to achieving partial weight-bearing, spanned approximately 15 weeks, including the two surgical procedures and staged rehabilitation. Post-surgery, the patient showed significant functional improvement, including the ability to stand and walk with assistance. Conclusion: The integration of advanced technologies in surgical planning for OI patients has shown promising results, leading to improved patient outcomes and reduced complications.

Keywords: Additive manufacturing , Computer aided design , Osteogenesis Imperfecta , Surgery planning

In radiotherapy treatments of mobile lesions, several strategies are used to treat the tumour while sparing the surrounding tissues [1]. The ADAM phantom (Anthropomorphic Dynamic breAthing Model) was developed to test dose delivery in lung cancer treatment. The aim of this study is to create ADAM A symbol representing the male gender, depicted as a circle with an arrow pointing diagonally upwards to the right. (Anthropomorphic Dynamic breAthing Model - Chemical structure diagram showing a hexagonal benzene ring with alternating double bonds. Attached to the ring is a hydroxyl group (OH) and a methyl group (CH3). The structure is labeled with standard chemical notation. male&female), a new modular phantom based on ADAM, to test free-breathing and deep inspiration breath hold (DIBH) breast radiotherapy treatments [2, 3]. The 3D model of ADAM was reconstructed using computed tomography (CT) scans to ensure a high level of anatomical accuracy. This digital model of ADAM served as the starting point for the design and development of ADAM Symbol representing a combination of male and female gender symbols, featuring a circle with an arrow pointing diagonally upward to the right and a cross extending downward. . 3D printable materials with tissue mimicking properties were selected to replicate tissues and organs [4, 5, 6, 7, 8–9]. The torso and chest were printed in PLA and the ribs and spine were printed in PLA StoneFil™ [10]. Tests have shown that ADAM A symbol representing the male gender, depicted as a circle with an arrow pointing diagonally upwards to the right. closely mimics human tissue in terms of Hounsfield Units. Its modular structure allows rapid transition between male and female configurations, making it suitable for realistic simulation of many clinical situations. ADAM A symbol combining the male and female gender symbols, featuring a circle with an arrow pointing diagonally upwards to the right and a cross extending downwards. demonstrates adequate performance for future testing gating and tracking devices in the treatment of moving breast and lung lesions. Chemical structure diagram showing a hexagonal benzene ring with alternating double bonds. Attached to the ring is a hydroxyl group (OH) and a methyl group (CH3). The structure is labeled with standard chemical notation.

Keywords: 3D Modelling , 3D Printing , Anthropomorphic Breathing Phantom , Tissue Mimicking

This study investigates post-processing treatments aimed at enhancing the mechanical properties of Polyether Ether Ketone (PEEK) parts fabricated via Fused Filament Fabrication (FFF). FFF-printed PEEK components often exhibit anisotropy and weak interlayer adhesion, which limit their structural performance. To address these issues, a resin infiltration treatment is proposed that yields improvements in flexural strength and strength-to-weight ratio across specimens with different infill percentages. The effectiveness of resin infiltration is compared to that of a thermal post-processing treatment. Experimental results indicate that, although thermal treatment enhances crystallinity, it does not substantially improve interlayer bonding or mitigate anisotropy. In contrast, resin infiltration significantly enhances flexural strength, particularly in specimens with lower infill percentages, by effectively filling pores and reinforcing interlayer adhesion. Overall, the findings demonstrate that vacuum-assisted thermosetting resin infiltration is a promising post-processing technique for improving the mechanical performance of 3D-printed PEEK, achieving a mean flexural strength of up to 34 MPa, approximately 80% higher than that of untreated specimens with 100% infill. Additionally, a cost analysis comparing both post-processing methods is presented, highlighting the cost-effectiveness of resin infiltration as a viable solution to overcome the inherent limitations of FFF-printed PEEK.

Keywords: Fused Filament Fabrication , interlayer adhesion , Polyether ether ketone PEEK , resin infiltration , thermal post-processing