Fusion Deposition Research Articles

3D-Printed Piezoelectret Based on Foamed Polylactic Acid for Energy-Harvesting and Sensing Applications.

Poly(lactic) acid (PLA) is a bio-compatible polymer widely used in additive manufacturing, and in the form of cellular foam it shows excellent mechanical and piezoelectric properties. This type of structure can be easily 3D-printed by Fusion Deposition Modelling (FDM) with commercially available composite filaments. In this work, we present mechanical and electrical investigations on 3D-printed low-cost and eco-friendly foamed PLA. The cellular microstructure and the foaming degree were tuned by varying extrusion temperature and flowrate. The maximum surface potential and charge stability of disk samples were found in correspondence of extrusion temperature between 230 and 240 °C with a flowrate of 53-44% when charging on a heated bed at 85 °C. The cells' morphology and correlated mechanical properties were analyzed and the measured piezoelectric d33 coefficient was found to be 212 pC/N. These findings show the importance of printing parameters and thermal treatment during the charging process in order to obtain the highest charge storage, stability and material flexibility. These results suggest that 3D-printed cellular PLA is a promising sustainable material for sensing and energy-harvesting applications.

Mechanical Characterization of Polylactic Acid Composite Scaffolds Formed in Different Lattice Structures by Fused Deposition Modeling-Based 3D Printing

Mechanical Characterization of Polylactic Acid Composite Scaffolds Formed in Different Lattice Structures by Fused Deposition Modeling-Based 3D Printing

Development of 3D-Printed Bicompartmental Devices by Dual-Nozzle Fused Deposition Modeling (FDM) for Colon-Specific Drug Delivery.

Dual-nozzle fused deposition modeling (FDM) is a 3D printing technique that allows for the simultaneous printing of two polymeric filaments and the design of complex geometries. Hence, hybrid formulations and structurally different sections can be combined into the same dosage form to achieve customized drug release kinetics. The objective of this study was to develop a novel bicompartmental device by dual-nozzle FDM for colon-specific drug delivery. Hydroxypropylmethylcellulose acetate succinate (HPMCAS) and polyvinyl alcohol (PVA) were selected as matrix-forming polymers of the outer pH-dependent and the inner water-soluble compartments, respectively. 5-Aminosalicylic acid (5-ASA) was selected as the model drug. Drug-free HPMCAS and drug-loaded PVA filaments suitable for FDM were extruded, and their properties were assessed by thermal, X-ray diffraction, microscopy, and texture analysis techniques. 5-ASA (20% w/w) remained mostly crystalline in the PVA matrix. Filaments were successfully printed into bicompartmental devices combining an outer cylindrical compartment and an inner spiral-shaped compartment that communicates with the external media through an opening. Scanning electron microscopy and X-ray tomography analysis were performed to guarantee the quality of the 3D-printed devices. In vitro drug release tests demonstrated a pH-responsive biphasic release pattern: a slow and sustained release period (pH values of 1.2 and 6.8) controlled by drug diffusion followed by a faster drug release phase (pH 7.4) governed by polymer relaxation/erosion. Overall, this research demonstrates the feasibility of the dual-nozzle FDM technique to obtain an innovative 3D-printed bicompartmental device for targeting 5-ASA to the colon.

Development of a Bilayer Tablet by Fused Deposition Modeling as a Sustained-Release Drug Delivery System.

Three-dimensional printing by fused deposition modeling (FDM) coupled with hot-melt extrusion (HME) is a point of convergence of research efforts directed toward the development of personalized dosage forms. In addition to the customization in terms of shapes, sizes, or delivered drug doses, the modulation of drug release profiles is crucial to ensure the superior efficacy and safety of modern 3D-printed medications compared to those of conventional ones. Our work aims to solidify the groundwork for the preparation of 3D-printed tablets that ensure the sustained release of diclofenac sodium. Specifically, we achieved the fast release of a diclofenac sodium dose to allow for the prompt onset of its pharmacological effect, further sustaining by the slow release of another dose to maintain the effect over a prolonged timeframe. In this regard, proper formulation and design strategies (a honeycomb structure for the immediate-release layer and a completely filled structure for the sustained-release layer) were applied. Secondarily, the potential of polyvinyl alcohol to function as a multifaceted polymeric matrix for both the immediate and slow-release layers was explored, with the objective of promoting the real-life applicability of the technique by downsizing the number of materials required to obtain versatile pharmaceutical products. The present study is a step forward in the translation of HME-FDM-3DP into a pharmaceutical manufacturing methodology.

FDM 3D printing application for making plate pattern on sand casting

Pattern making in sand casting requires high-level skilled workers since accuracy is the most important concern in producing good quality products. Therefore, conventional pattern-making becomes a major obstacle in developing new products, especially for complicated products as it takes over 70% of the total time in production of the foundry process. This study offers an alternative method in pattern making utilizing 3D technology with the Fuse Deposition Material (FDM) method. It consisted of three steps: planning, production, and evaluation. An intake manifold is an example product that was designed by using Computer Aided Design (CAD) and then imported to a slicer application to obtain the G codes. After the design was printed by using filament of PLA+, it was assembled to create the plate pattern that then was used to produce the intake manifold through casting. The study result shows that the FDM method of the 3D printing technology is feasible for pattern making on sand casting. Deviation and shrinkage of the casting product were still within tolerance. The largest shrinkage is 0.453 mm (1.258%).

Study on the Evolution Mechanism of the Structure and Properties of ABS in Cycled Fused Deposition Molding (FDM)

Study on the Evolution Mechanism of the Structure and Properties of ABS in Cycled Fused Deposition Molding (FDM)

Development of 3D-Printed Self-Healing Capsules with a Separate Membrane and Investigation of Mechanical Properties for Improving Fracture Strength

Studies on self-healing capsules embedded in cement composites to heal such cracks have recently been actively researched in order to improve the dimensional stability of concrete structures. In particular, capsule studies were mainly conducted to separately inject reactive healing solutions into different capsules. However, with this method, there is an important limitation in that the probability of self-healing is greatly reduced because the two healing solutions must meet and react. Therefore, we propose three-dimensional (3D) printer-based self-healing capsules with a membrane structure that allows two healing solutions to be injected into one capsule. Among many 3D printing methods, we used the fusion deposition modeling (FDM) to design, analyze, and produce new self-healing capsules, which are widely used due to their low cost, precise manufacturing, and high-speed. However, polylactic lactic acid (PLA) extruded in the FDM has low adhesion energy between stacked layers, which causes different fracture strengths depending on the direction of the applied load and the subsequent performance degradation of the capsule. Therefore, the isotropic fracture characteristics of the newly proposed four types of separated membrane capsules were analyzed using finite element method analysis. Additionally, capsules were produced using the FDM method, and the compression test was conducted by applying force in the x, y, and z directions. The isotropic fracture strength was also analyzed using the relative standard deviation (RSD) parameter. As a result, the proposed separated membrane capsule showed that the RSD of isotropic fracture strength over all directions fell to about 18% compared to other capsules.

Statistical Comparison of the Mechanical Properties of 3D-Printed Resin through Triple-Jetting Technology and Conventional PMMA in Orthodontic Occlusal Splint Manufacturing.

Dental 3D-printing technologies, including stereolithography (SLA), polyjet (triple-jetting technology), and fusion deposition modeling, have revolutionized the field of orthodontic occlusal splint manufacturing. Three-dimensional printing is now currently used in many dental fields, such as restorative dentistry, prosthodontics, implantology, and orthodontics. This study aimed to assess the mechanical properties of 3D-printed materials and compare them with the conventional polymethylmethacrylate (PMMA). Compression, flexural, and tensile properties were evaluated and compared between PMMA samples (n = 20) created using the "salt and pepper" technique and digitally designed 3D-printed samples (n = 20). The samples were subjected to scanning electron microscope analysis. Statistical analysis revealed that the control material (PMMA) exhibited a significantly higher Young's modulus of compression and tensile strength (p < 0.05). In the flexural tests, the control samples demonstrated superior load at break results (p < 0.05). However, the 3D-printed samples exhibited significantly higher maximum bending stress at maximum load (MPa) (p < 0.05). Young's modulus of tensile testing (MPa) was statistically significant higher for the control samples, while the 3D-printed samples demonstrated significantly higher values for elongation at break (p < 0.05). These findings indicate that 3D-printed materials are a promising alternative that can be effectively utilized in clinical practice, potentially replacing traditional heat-cured resin in various applications.

Fabrication and characterization of PMMA/ZrO2 nanocomposite 3D printing filaments

AbstractThe 3D printing PMMA/ZrO2 filaments with a diameter of 1.75 ± 0.05 mm were fabricated by using a single‐screw extruder at temperatures of four heating zones of 190, 200, 210, and 210°C. Testing samples were prepared from the extruded filaments by using a fusion deposition modeling 3D printer and a Haake MiniJet piston injection molding machine. Fourier transform infrared spectroscopy, mechanical properties, field emission scanning electron microscopy (FESEM), differential scanning calorimetry, and thermogravimetric analysis of the filaments were investigated. It was suggested the formation of physical and molecular interactions between surface hydroxyl groups of ZrO2 nanoparticles and C‐O‐C groups of PMMA in the PMMA/ZrO2 filaments. FESEM images of the filaments indicated the good dispersion of ZrO2 nanoparticles in the PMMA matrix, nevertheless, there was still the formation of clusters of ZrO2 nanoparticles in the nanocomposite filaments. The incorporation of nano ZrO2 increased the thermal properties, bending, and tensile moduli of PMMA. The mechanical properties of the 3D‐printed samples were lower than those of the molded samples. However, the bending strength of the 3D‐printed samples was much higher than 50 MPa, bending modulus was much higher than 1800 MPa, as required for acrylic bone cement (in ISO 5833:2002).

Advantages of FDM and gamma irradiation to manufacture personalized medical devices for airway obstructions.

In the early childhood population, congenital airway conditions like bronchomalacia (BM) can pose a life-threatening threat. A breakthrough technology called additive manufacturing, or 3D printing, makes it feasible to create a biomedical device that aids in the treatment of airway obstruction. This article describes how a polycaprolactone (PCL) splint for the upper airways can be created using the fusion deposition technique (FDM) and sterilized using gamma radiation. It is presented as a simple, accessible, and cost-reduced alternative that complements other techniques using more expensive and sophisticated printing methods. Thermomechanical and morphological analysis proved that FDM and sterilizing by gamma irradiation are both appropriate methods for producing splints to treat life-threatening airway blockages. Additionally, the 3D-printed splints' effectiveness in treating a young patient with BM that was life-threatening was assessed by medical professionals. In this regard, the case report of a patient with 34months of follow-up is presented. Splints manufactured by this affordable 3D printing method successfully surpass breathing arrest in life-threatening airway obstruction in pediatric patients. The success of this procedure represents a fundamental contribution to the treatment of the population in countries where access to expensive and complex technologies is not available.

Energy absorbing 4D printed meta-sandwich structures: load cycles and shape recovery

The present study investigates the behavior of solid cellular structures in polylactic acid (PLA) achieved by FDM technology (fusion deposition modelling). The geometries are permanently deformed by compressive stress and then subjected to shape recovery through the application of a thermal stimulus. The structures are submitted to medium–high and medium–low compression stresses, evaluating the mechanical properties and the absorption energy as the number of cycles varies. The study shows that the ability to absorb energy is related to the density of the model, as well as the degree of damage observed, which increases with increasing number of load cycles. The strongest geometry is the lozenge grid, which is the most reliable. It shows no damage with increasing compression cycles and keeps its capability to absorb energy almost constant. The increase in lozenge grid density leads to an improvement in both mechanical strength and absorption energy, as well as a lower incidence of microcracks in the geometry itself due to the repeated load cycles. These results open up a broad spectrum of applications of custom-designed solid cellular structures in the field of energy absorption and damping.

Conductive Filament Composites from Waste Battery Rod-Derived Exfoliated Graphite for Fused Deposition Modeling 3D Printing: A Two-Level Factorial Design Optimization Study

This study used carbon rods from spent zinc-carbon batteries as a source of exfoliated graphite (EG) to produce conductive filament composites for fused deposition modeling 3D printing. The EG filler was prepared through microwave irradiation, while the resulting 3D printable electroconductive EG composites were prepared using polylactic acid (PLA) and polyethylene glycol (PEG) as the polymer matrix and compatibilizer, respectively, via a sonication-assisted solution blending and melt extrusion process. A two-level full factorial design was employed to fully investigate the influence of filament production parameters such as EG loading, PEG:PLA ratio, and sonication time on the resistivity (i.e., conductivity-1) of the prepared composites. Analysis of variance showed that both EG loading and sonication time had significant effects on the resistivity of the composites. The optimum electrical resistivity of the new EG filament composites was found to be 916.418 Ω-cm (maximum conductivity = 1.091 x10-3 S/cm) at EG loading = 45 % w/w, PEG:PLA ratio = 1:10, and sonication time = 2 hours. The conductivity of the 3D printed composites was also correlated with EG amount by the power law model of percolation theory, resulting in an electrical percolation threshold at around 35 % w/w of EG. Our filament composites enable the fabrication of high-value conductive materials from waste resources for sustainable additive manufacturing in the electronics industry.

Experimental study of manufacturing of human mandible using fusion deposit modeling (rapid prototyping)

Rapid prototyping method is used, for the manufacture of human mandible for replacement for accident victims. Rapid prototyping will make the manufacture of implants much easier and more exact than conventional methods such as titanium implant manufacturing in Alveolar ridge augmentation. After performing the necessary tests, the material selected for usage in the implants was ABS (Acrylonitrile Butadiene Styrene). Tensile tests are performed on ABS for implant manufacturing. Structured Light 3D Scanner is used to scan a life-size human mandible and the Standard Triangular Language (STL) file was created that file has been used in all the processes involved in the modeling and manufacturing of the Human Mandible by Rapid prototyping on ABS. FEM analysis is done on said material at different orientations using ANSYS 2021. From the test results it is found that the ABS material can sustain more than the required average bite force. Furthermore, a comparison of stress and load-bearing ability of bone and ABS is done to confirm the viability as a replacement material for bone in the mandible, which was found to be positive. The biocompatibility of ABS with the bloodstream and the body is researched and found to be positive. Implantation methods and bone powder coating variants are researched, to be able to fit the implant in the temporomandibular joint with the fastest recovery time.

Study on track width of various curvature angles in laser powder bed fusion deposition

Study on track width of various curvature angles in laser powder bed fusion deposition

Characterization of fused deposition modeling components fabricated at different print orientations

The quality of the components fabricated using fusion deposition modelling (FDM) can be tailored by the proper selection of process parameters values. Print orientation is a key process parameter in FDM which has a strong influence on defect formation and thereby mechanical properties of the components. To address the influence of print orientation, FDM of Polyethylene terephthalate glycol (PETG) samples were fabricated and tested. The samples were fabricated using different print orientations namely 0°, 45°, 90° and combination of 45° and 135° alternatively. From the investigation, it was inferred that the print orientation is crucial in deciding the part properties attributing towards the load bearing capacity of print seams. The print orientation of 90° exhibit higher strength by exhibiting peak load values of 942 N and higher elongation of 128 mm. The elongation capability is more than 40 times higher than the 0°, 45°, and 45°/135° orientations which is attributed to the availability of continuous and longer print seam that supports load bearing and elongation.

A Decision-Making Carbon Reinforced Material Selection Model for Composite Polymers in Pipeline Applications

Pipes are manufactured primarily through the extrusion process. One of the material extrusion processes in recent digital manufacturing is additive manufacturing’s fusion deposition modeling. Pipes are made from various materials such as metal and plastic/polymers, and the main challenge has been in selecting the pipe material for the customized application. For the creation of water-passing tubes, this research has chosen appropriate carbon-reinforced polymers that can be used with filament made of polyether ether ketone (PEEK) and polyethylene terephthalate glycol (PETG). For this goal, the analytical hierarchy process, also known as the AHP, is used to choose the best material based on factors such as cost, temperature resistance, printing speed, and mechanical properties of the material. The results revealed that PEEK-CF is a better material for the customized impeller application than PETG-CF. The PEEK-CF obtains the higher priority value of 0.6363, and the PETG-CF obtains 0.2791. This decision-making technique can be used to select other comparable customized applications.

Optimization and Experimental Investigation of 3D Printed Micro Wind Turbine Blade Made of PLA Material

This paper presents the design, development, and optimization of a 3D printed micro horizontal axis wind turbine blade made of PLA material. The objective of the study was to produce 100 watts of power for low-wind-speed applications. The design process involved the selection of SD7080 airfoil and the determination of the material properties of PLA and ABS. A structural analysis of the blade was carried out using ANSYS software under different wind speeds, and Taguchi's L16 orthogonal array was used for the experiments. The deformation and equivalent stress of the PLA material were identified, and the infill percentage and wind speed velocity were optimized using the moth-flame optimization (MFO) algorithm. The results demonstrate that PLA material has better structural characteristics compared to ABS material. The optimized parameters were used to fabricate the turbine blades using the fusion deposition modeling (FDM) technique, and they were tested in a wind tunnel.

Study of Phase Evolution Behavior of Ti6Al4V/Inconel 718 by Pulsed Laser Melting Deposition

In this study, a pulsed laser was used as the heat source for the additive work. The Ti6Al4V/Inconel 718 alloy wire was deposited on the substrate by melting using a pulsed laser. Using the above method, single-layer and double-layer samples were printed. The sample material printed in this way is highly utilized. Compared to the complicated pre-preparation work of metal powder pre-mixing, this printing method is simple to prepare and only requires changing the wire feeding speed. The study of this paper provides a theoretical guide for the subsequent fusion deposition of heterogeneous wire materials. The samples were analyzed after molding using SEM, EDS and XRD to characterize the microstructure of the samples. The samples can be divided into three zones depending on the microstructure, the bottom columnar crystal zone, the middle mixed phase zone, and the bottom equiaxed crystal zone. From the bottom to the top of the sample, the phase microstructure changes as γ + Laves → α + β + Ti2Ni + TiNi + Ni3Ti → α + β. The hardness data show that the highest value in the transition zone is 951.4 HV. The hardness of the top part is second only to the transition zone due to a large number of equiaxed crystals. The bottom region is dominated by columnar crystals and is the softest of the three regions with the lowest hardness value of 701.4 HV.

Enhancement of 3D Printability by FDM and Electrical Conductivity of PLA/MWCNT Filaments Using Lignin as Bio-Dispersant.

To increase the applications of FDM (fusion deposition modeling) 3D printing in electronics, it is necessary to develop new filaments with good electrical properties and suitable processability. In this work, polymer composites filament-shaped with superior electrical performance based on polylactic acid (PLA) carbon nanotubes and lignin blends have been studied by combining solution mixing and melt blending. The results showed that composites achieve electrical percolation from 5 wt.% of nanotubes, with high electrical conductivity. Moreover, the introduction of a plasticizing additive, lignin, improved the printability of the material while increasing its electrical conductivity (from (1.5 ± 0.9)·10-7 S·cm-1 to (1.4 ± 0.9)·10-1 S cm-1 with 5 wt.% carbon nanotubes and 1 wt.% lignin) maintaining the mechanical properties of composite without additive. To validate lignin performance, its effect on PLA/MWCNT was compare with polyethylene glycol. PEG is a well-known commercial additive, and its use as dispersant and plasticizer in PLA/MWCNT composites has been proven in bibliography. PLA/MWCNT composites display easier processability by 3D printing and more adhesion between the printed layers with lignin than with PEG. In addition, the polyethylene glycol produces a plasticizing effect in the PLA matrix reducing the composite stiffness. Finally, an interactive electronic prototype was 3D printed to assess the printability of the new conducting filaments with 5 wt.% of MWCNT.

Effect of the number of stiffeners on the lateral deformation behavior of additively manufactured thin-walled cylindrical tubes

Nowadays, thin-walled cylindrical tubes with stiffeners have been rapidly considered in crashworthiness applications owing to their outstanding energy absorption characteristics and comparatively light weight. This research article deals with the influence of the internal linear stiffeners with varying numbers on the lateral crushing characteristics and impact energy absorbing response of cylindrical tubes subjected to quasi-static loading through experimental approaches. Five different configurations were proposed and all the tubes were additively manufactured through Fusion Deposition Modeling (FDM)-based 3 D printing method. Eventually, the fabricated tubes were tested under quasi‐static lateral crushing force and their crashworthiness characteristics were determined. The obtained results revealed that the PLA-CF-based C6S tube exhibited Specific Energy Absorption of 4.99 kJ/g and attained Crush Force Efficiency is 98.68%. Overall outcomes reported that both the carbon fiber reinforced polymer composite tube structures presented better crushing behavior and enhanced energy absorbing capability. Therefore, the proposed linear stiffener induced cylindrical tubes could be employed as a crash box for absorbing energy under lateral impact.