Fused Deposition Modeling 3D Printing Research Articles

3D-Printed Gastroretentive Sustained Release Drug Delivery System by Applying Design of Experiment Approach.

This study aimed to develop a novel oral drug delivery system for gastroretentive sustained drug release by using a capsular device. A capsular device that can control drug release rates from the inner immediate release (IR) tablet while floating in the gastric fluid was fabricated and printed by a fused deposition modeling 3D printer. A commercial IR tablet of baclofen was inserted into the capsular device. The structure of the capsular device was optimized by applying a design of experiment approach to achieve sustained release of a drug while maintaining sufficient buoyancy. The 2-level factorial design was used to identify the optimal sustained release with three control factors: size, number, and height of drug-releasing holes of the capsular device. The drug delivery system was buoyant for more than 24 h and the average time to reach 80% dissolution (T80) was 1.7–6.7 h by varying the control factors. The effects of the different control factors on the response factor, T80, were predicted by using the equation of best fit. Finally, drug delivery systems with predetermined release rates were prepared with a mean prediction error ≤ 15.3%. This approach holds great promise to develop various controlled release drug delivery systems.

In-situ X-ray scattering study of isotactic polypropylene/graphene nanocomposites under shear during fused deposition modeling 3D printing

Complementary techniques were applied to characterize the structure property relationships of FDM printed isotactic polypropylene/graphene nanocomposites. Raman spectroscopy indicated that graphene was mostly exfoliated during the nozzle extrusion process. Rheological measurements of the viscosity indicated that the presence of graphene induced shear thinning during extrusion. Azimuthal scans of wide angle x-ray scattering indicate correlated thermal fluctuations of the graphene platelets which stops abruptly at the onset of transcrystallization, or templating of the iPP chains on the graphene. X-ray microbeam SAXS analysis show the formation of ‘shish-kebab’ structures at the core of the unfilled filaments, where the ‘kebab’ component vanishes at the fiber-fiber interface enabling interdiffusion. Weak lamellar structure, and a corresponding decrease in the storage modulus are observed with the addition of 5% graphene. The lamellar structure disappears entirely with the addition of 10% graphene, while the storage modulus is decreased by nearly 50%. Thermal imaging of heat flux dissipation across molded and printed samples shows no orientational effects in pure iPP despite differences in crystal structure. Thermal conductivity increases dramatically in the samples with 10% graphene, and strong orientational effects are observed where the thermal coefficients differ by 180% between samples printed parallel or perpendicular to the heat flux.

Additive Analytics: Easy Transformation of Low-Cost Fused Deposition Modeling Three-Dimensional Printers for HPTLC Sample Application.

Additive manufacturing, known as three-dimensional (3D) printing technologies, has revolutionized production in all domains of science and technology. Although 3D printing has a high impact on research and development, its capacity to implement low-cost, flexible, and robust sample handling automation has not been exploited in full. To this end, we have created a low-cost, robust, and easy-to-utilize kit to transform an off-the-shelf fused deposition modeling 3D printer to a thin layer chromatography (TLC) sample application device. Our technology solution improves TLC convenience when higher throughput of the established method is required. The developed dual-needle sprayer allows simple and exceptionally robust automatic sample application. The device is especially well-suited for high-performance TLC-assisted method selection in counter-current chromatography. A step-by-step guide and list of required parts, including 3D printable files with instruction, can be obtained from the Supporting Information for research usage and open development.

Enhancing interlayer bonding strength of FDM 3D printing technology by diode laser-assisted system

Fused deposition modeling (FDM) is the most widespread 3D printing technology. The primary reasons for this are its simplicity in manufacturing and low cost. The common issue of FDM is an anisotropic property of the extruded layer. Therefore, the mechanical strength of traditional machining methods is significantly better than FDM-fabricated parts. Implementation of diode laser (450 nm) with 5 W power for localized heating of the pre-deposition layer is proposed to overcome this problem. The laser power is controlled during the printing process. Thereby, layer interface temperature reached for critical point, where the bonding diffusion process between layers increased for the maximum level. The effect of the pre-deposing heating method is presented at different laser power values and printing speed. Tensile test results on PLA (polylactic acid) plastic specimen indicate a 10.16% increase in ultimate tensile strength at 2.84 W power of the laser. However, crack and hole formations indicate a negative result of intensive laser heating employment.

3D Printing of Polyethylene Terephthalate Glycol-Sepiolite Composites with Nanoscale Orientation.

A fused-deposition modeling (FDM) 3D-printed polyethylene terephthalate glycol (PETG)-sepiolite composite showed effective synergetic mechanical reinforcement in tensile testing compared to an injection-molded composite. The results showed that the addition of 3 phr sepiolite improved the tensile strength of 3D-printed PETG samples by 35.4%, while the tensile strength of injection-molded PETG samples was improved by 7.2%. To confirm these phenomena, FDM PETG-sepiolite composites were investigated by small-angle X-ray scattering to correlate the nanostructures of the composites with their mechanical strengths. The small-angle X-ray scattering data and transmission electron microscopy observations demonstrated that needle-shaped sepiolite particles were aligned in the printing direction. This fine oriented nanostructure formed during 3D printing created a synergistic effect that improved the material properties of the composite. These novel PETG-sepiolite composites with enhanced mechanical properties can be promising materials fabricated via FDM 3D printing.

Amplitude Uniformity in Ultrasonic Assisted Fused Deposition Modeling

Fused Deposition Modeling (FDM) is one of the Additive Manufacturing (AM) technology. Ultrasonic-assisted FDM system has been proven to improve the mechanical properties of the printed specimens. This study aims to explore the uniformity of the amplitude of ultrasonic vibration that was used during the printing process. The uniformity of vibration affected the improvement of the mechanical properties of the 3D printed part. If there is a bad uniformity of ultrasonic vibration, it will influence and increase the variation of the tensile test result. An open-source FDM printer attached with the piezoelectric transducer in various locations of the printer platform was set up. Five different positions and numbers of piezoelectric transducer were set up in order to determine the best position and number of the piezoelectric transducer for transmitting the vibration uniformly to the printing platform. A laser scanning vibrometer was used to determine the amplitude of ultrasonic vibration that transmitted over the printing platform of an open-source FDM 3D printer. From the results, it shows that with two piezoelectric transducers at “Position 4” improved the uniformity of ultrasonic vibration as it had the lowest standard deviation. The test also revealed that the ultrasonic vibration effect uniformly on the 3D printed specimens. In addition, it also reduces the variation and provide better tensile test results of the printed specimens

Low-cost FDM 3D-printed modular electrospray/electrospinning setup for biomedical applications

Here, we report on the inexpensive fabrication of an electrospray/electrospinning setup by fused deposition modelling (FDM) 3D printing and provide the files and parameters needed to print this versatile device. Both electrospray and electrospinning technologies are widely used for pharmaceutical, healthcare and bioengineering applications. The setup was designed to be modular, thus its parts can be exchanged easily. The design provides a safe setup, ensuring that the users are not exposed to the high voltage parts of the setup. PLA, PVA, and a thermoplastic elastomer filament were used for the 3D printing. The filament cost was $100 USD and the rig was printed in 6 days. An Ultimaker 3 FDM 3D printer was used with dual print heads, and the PVA was used as a water-soluble support structure. The end part of the setup had several gas channels, allowing a uniform gas flowing against the direction of the nanoparticles/nanofibers, enhancing the drying process by enhancing the evaporation rate. The setup was tested in both electrospray and electrospinning modes successfully. Both the .sldprt and .stl files are provided for free download.

Assessment of 3D printing using fused deposition modeling and selective laser sintering for a circular economy

Plastic today is commonplace. Products and parts made with plastic have short life cycles, ending up in landfills not long after manufacture. Finding new pathways for plastic waste has become a critical focus of sustainability efforts, especially within manufacturing. Thus, research in this field continues to grow in order to determine the feasibility of reclaiming post-consumer plastic for reuse. This paper evaluates the potential for a sustainable, circular pathway for end-of-life plastic material using 3D-printing techniques. To do this, the work investigates two prevalent industrial 3D-printing technologies: selective laser sintering (SLS) and fused deposition modeling (FDM) of polymers. Material-flow and economic models are developed to outline how plastic parts at the end of their life cycle can be processed and reused. Prior works on fundamental material degradation are integrated into mathematical models of cost and operation. This enables mapping of how multiple reuse cycles affect two prevalent industrial polymers: acrylonitrile butadiene styrene (ABS) and polyamide 12 (PA 12). The mapping identifies there is significant opportunity for improving both SLS and FDM 3D-printing technologies when it comes to economic viability and sustainability. Comparison between reuse of FDM using ABS and SLS using PA 12 shows the former costs 82% less than the latter, while also producing 87% less waste than it. While the study established that available industrial 3D-printing technologies can help to reduce plastic waste within manufacturing, a fully circular economy demands materials with less thermal degradation than the primary industrial 3D-printing polymers.

Analysis of structural features and efficiency of application of modern FDM printers for 3D printing using polymer thermoplastic materials

This work presents the main parameters of the current state of the world market of additive manufacturing equipment. For research, the most common type of additive technology was chosen, namely FDM (Fused Deposition Modeling) or 3D printing using thermoplastic polymer material. This technology is the most common and is used in industry, engineering design, rapid prototyping, educational process, scientific research, medicine, design and the like. The main works were presented that consider the main characteristics of the equipment, systematize them according to design features and areas of application. Given the insufficient coverage of equipment types and designs in these works, an extensive review of devices based on FDM technology was carried out. The classification of equipment is based on the principle of moving executive bodies, namely the print head and the 3D printer working platform. Based on this, it has been established that there are four main schemes for constructing of 3D printers such as Cartesian, Delta, Polar and schemes based on a robotic manipulator. The most popular models of 3D printers for each of the circuits were given, their main advantages and disadvantages, areas and applications, examples of products manufactured were considered. The review showed that the most widespread in the scheme both in the world and in Ukraine is the Cartesian, which in turn is divided into a number of subspecies. Among them, Prusa, CoreXY and H-Bot schemes are especially popular. They are the most versatile, use almost all types of consumable thermoplastic material, include almost all the range of sizes needed for production of the working area and are the most flexible for modernization. FDM 3D printers based on a robotic arm were also noted. The development of this type of equipment is an example of the introduction of additive technologies in serial automated production. Consideration of the main areas of application and the main advantages and disadvantages of each of the types of 3D printers made it possible to give recommendations on the choice of equipment for spatial printing, depending on the type of activity.

Fabrication of Modified-Release Custom-Designed Ciprofloxacin Tablets Via Fused Deposition Modeling 3D Printing

Aim: The aim of the present work was to fabricate customized tablets of ciprofloxacin hydrochloride through 3D printing for optimized dosing. Materials & methods: A hot melt extrusion technique was employed to produce polyvinyl alcohol filaments with differing strengths of ciprofloxacin hydrochloride. Drug-loaded filaments were characterized for mechanical strength, thermal behavior and structural characteristics prior to printing of tablets by varying the infill percentage. Final formulations were evaluated for drug release profiles. Results: The prepared formulations contained 15–20% drug. The drug release patterns of different formulations were found to be reliant on infill percentage. Differential scanning calorimetry and thermo-gravimetric analysis confirmed that degradation temperature of drug is way above the printing temperature. Conclusion: This work is potentially significant for optimized antibiotic dosing, which in turn leads to enhanced clinical outcome.

Properties of 3D Printable Poly(lactic acid)/Poly(butylene adipate-co-terephthalate) Blends and Nano Talc Composites

Biodegradable poly(lactic acid) (PLA) filaments have been widely used in the fused deposition modeling (FDM) 3D printing technology. However, PLA has low toughness and low thermal resistance that affects printability and restricts its industrial applications. In this study, PLA was compounded with 0 to 40 wt% of poly(butylene adipate-co-terephthalate) (PBAT) and varied content of nano talc at 0 to 40 wt% in a twin screw extruder. The compounds were reextruded to filaments using a capillary rheometer. PLA/PBAT blends and their composite filaments were printed with a FDM 3D printing machine. Morphology, rheological behaviour, thermal characteristic, surface roughness, and mechanical property of 3D printing of the blends and the composites were investigated. Complex viscosity of the blends and the composites increased with increase of the PBAT and the nano talc contents. The incorporation of the nano talc enhanced crystallization temperature and reduced the coefficient of volume expansion of the composites. It was found that the PLA/PBAT blends and composites were excellent in both printability and dimension stability at PBAT content 10-30 wt% and nano talc up to 10 wt%. Interestingly, it was possible to print the composite filaments at an angle up to 75° during the overhang test without a supporter. From the vertical specimens, the surface roughness improved due to the incorporation of the nano talc. Tensile strength of the blends and the composites decreased, whereas elongation at break increased when the PBAT and the nano talc contents were increased. The reduction of tensile strength was attributed to agglomeration of the PBAT dispersed phase and less adhesion between the nano talc and the matrix. It can be noted that the composite 3D printing product showed superior elongation at break up to 410% by adding nano talc 1 wt%. This result suggests that the ductile 3D printable PLA/PBAT blend and the PLA/PBAT-nano talc composite products can be prepared, which shows potential for the commercialized scale.

Fused Deposition Modeling 3D Printing of Novel Poly(vinyl alcohol)/Graphene Nanocomposite with Enhanced Mechanical and Electromagnetic Interference Shielding Properties

Nowadays, there is a considerable demand for printable and functionalized thermoplastic polymer-based materials that are suitable for fused deposition modeling (FDM) three-dimensional (3D) printing. Hence, in this study, poly(vinyl alcohol) (PVA)/graphene nanoplate (GNP) multifunctional nanocomposites were thermally prepared for printing parts with enhanced electromagnetic interference (EMI) shielding capability via FDM. The related microstructure, processing parameters, and properties of the prepared PVA/GNP nanocomposite, as well as the printed parts, were accordingly investigated. The results indicated that ultrasonication realized the homogeneous dispersion of GNP fillers in the PVA matrix. The added glycerol and GNP effectively destroyed the intrinsic hydrogen bonds of PVA through molecular complexation interaction, thus broadening the processing window of PVA and its nanocomposite. Additionally, the incorporation of GNP also facilitated the enhancement in the hydrophobicity of the nanocomposite. The mechanical properties, including Young’s modulus, elongation at break, and ultimate tensile stress of the printed PVA/GNP parts, were optimized when the filling pattern was 0 × 0. Moreover, the EMI shielding efficiency (SE) of the printed PVA/GNP parts with a thickness of 2.43 mm reached 26–32 dB in the frequency range of 8–12.4 GHz, which can completely satisfy the requirements for practical applications. The corresponding EMI SE mechanism of the printed parts was also discussed.

Fabrication of thermoplastic functionally gradient composite parts with anisotropic thermal conductive properties based on multicomponent fused deposition modeling 3D printing

Abstract A multicomponent fused deposition modeling 3D printing approach was proposed to fabricate thermoplastic functionally gradient composite parts (TFGCPs). The thermal conductive properties of the fabricated TFGCPs were studied by slice and as integrate, respectively. The variation of thermal conductivity by slice versus the number of layer shows that the curve of PCL/AlN has a constant slope, while the one of PCL/BN first increases and then decreases. It is attributed to that the network of thermal conduction is constructed when the loading of BN particles approaches 27wt%, leading to a substantial growth in thermal conductivity. The thermal conductivity of the TFGCPs as integrate lies between the one of pure PCL and homogeneous composite parts with AlN or BN fillers and has a relationship with the filler loading direction exhibiting thermal anisotropy. This study establishes the relationship between properties and structures of thermoplastic functionally gradient composite parts, which helps to lay a theoretical foundation of applications as intermediate layers.

Impact of 3D-printing structure on the tribological properties of polymers

Purpose The purpose of this paper is to examine the impact of three-dimensional (3D)-printing process settings (particularly print orientation) on the tribological properties of different polymers. Design/methodology/approach In this study, fused deposition modelling 3D-printing technology was used for fabricating the specimens. To evaluate the influence of print orientation, the test pieces were manufactured horizontally (X) and vertically (Z). The tribological properties of various printed polymers, which are polylactide acid, high tensile/high temperature-polylactide acid and polyethylene terephthalate-glycol have been studied. The tribological tests have been carried out under reciprocating sliding and dry condition. Findings The results show that the presence of various orientations during the 3D-printing process makes a difference in the coefficient of friction and the wear depth values. Findings suggest that printing structure in the horizontal orientation (X) assists in reducing friction and wear. Originality/value To date, there has been very limited research on the tribology of objects produced by 3D printing. This work was made as an attempt to pave the way for future research on the science of tribology of 3D-printed polymers.

Numerical and experimental analysis of the 3D printed multi-material ankle-foot orthosis

The application of 3D printing in medicine is the major area to concern in the nearest future. Namely, it is convenient to additively manufacture the Ankle-Foot Orthosis (AFO) by fused-deposition modeling 3D printer. AFO is the device, used in medicine, to help the patients rehabilitate from the foot drop disease. The shape of the AFO may vary depending on the leg and foot specifications of the patient. In this paper, three models of the AFO were designed to analyze both numerically and experimentally, those are fracture propagation, stress distribution, and deformation. The regions with the highest stress concentration were altered with the Nylon 12, and this contributed to stress reduction. Three different gait instances were considered for the numerical simulations FEA software. Then, the simplest model to prototype and its modified versions were tested by the compression machine, and the results were compared with the numerical ones. This work demonstrated the significance of the optimization of the multi-material 3D printed AFO’s performance and comfort for patients.

Lego-Inspired Capsular Devices for the Development of Personalized Dietary Supplements: Proof of Concept With Multimodal Release of Caffeine

Dietary supplement companies have recently started to focus on the personalization of products and the improvement of the relevant performance. In this respect, a versatile, easy-to-handle capsular delivery platform with customizable content and release kinetics was here proposed and evaluated after filling with caffeine as a model dietary ingredient. In particular, capsular devices comprising 1 to 3 independent inner compartments were attained by Lego-inspired assembly of matching modular units with different wall compositions, manufactured by injection molding and fused deposition modeling 3D printing. Accordingly, one-, two- and three-pulse release profiles of the dietary ingredient were obtained from differently assembled devices following the breakup of the compartments occurring promptly (immediate-release), on pH change (delayed-release) or after tunable lag times (pulsatile-release). The latter release mode would enable the onset of the stimulating effect of caffeine at different times of the day after a single administration when convenient. The performance of each individual compartment only depended on the composition (i.e., promptly soluble, swellable/soluble or enteric soluble polymers) and thickness of its own wall, while it was not affected by the composition and number of joined modular units. Moreover, the delivery platform was extended to include an external gastroresistant shell enclosing previously assembled devices.

Orientation Planning in the Fused Deposition Modeling 3D Printing of Anatomical Spine Models.

Three‐dimensional (3D) printing has revolutionized medical training and patient care. Clinically it is used for patient‐specific anatomical modeling with respect to surgical procedures. 3D printing is heavily implemented for simulation to provide a useful tool for anatomical knowledge and surgical techniques. Fused deposition modeling (FDM) is a commonly utilized method of 3D printing anatomical models due to its cost-effectiveness. A potential disadvantage of FDM 3D printing complex anatomical shapes is the limitations of the modeling system in providing accurate representations of multifaceted ultrastructure, such as the facets of the lumbar spine. In order to utilize FDM 3D printing methods in an efficient manner, the pre-printing G-code assembly must be oriented according to the anatomical nature of the print. This article describes the approach that our institution's 3D printing laboratory has used to manipulate models’ printing angles in regard to the print bed and nozzle, according to anatomical properties, thus creating quality and cost-effective anatomical spine models for education and procedural simulation.

Tensile failure strength and separation angle of FDM 3D printing PLA material: Experimental and theoretical analyses

It is discovered in this investigation that there exist two different failure modes and a special separation angle which is the demarcation point of the two different failure modes when FDM (Fused Deposition Modelling) 3D printing materials fail under a tensile load. In order to further understand the mechanical properties of FDM 3D printing materials and promote the use of FDM 3D printing materials, their tensile failure strengths at different printing angles and separation angles are measured and analysed theoretically. A new separate-modes of transversely isotropic theoretical failure model is established to predict the tensile failure strength and separation angle of FDM 3D printing PLA (polylactic acid) material based on the hypothesis of transverse isotropy and the classical separate-modes failure criterion. During this research, the tensile specimens designed according to the current test standard ISO (527-2-2012) for plastic-multi-purpose specimens are fabricated in 7 different printing angles (0∘, 15∘, 30∘, 45∘, 60∘, 75∘, 90∘) and three levels of printing layer thickness (0.1 mm, 0.2 mm, 0.3 mm). Experimental results show that the tensile failure strength increases with the increase of the printing angle or the decrease of the layer thickness. Meanwhile, inter-layer failure tends to occur when the printing angle is small and in-layer failure tends to occur when the printing angle is big. In comparison with the results predicted by the established theoretical model, all values of the Generalized-Relative-Root-Mean-Square Error are close to zero and the experimental separation angles are also between 45∘ and 60∘. So the predictive capacity of the theoretical model is affirmed by experimental results.

Topology Optimization for Multipatch Fused Deposition Modeling 3D Printing

This paper presents a hybrid topology optimization method for multipatch fused deposition modeling (FDM) 3D printing to address the process-induced material anisotropy. The ‘multipatch’ concept consists of each printing layer disintegrated into multiple patches with different zigzag-type filament deposition directions. The level set method was employed to represent and track the layer shape evolution; discrete material optimization (DMO) model was adopted to realize the material property interpolation among the patches. With this set-up, a concurrent optimization problem was formulated to simultaneously optimize the topological structure of the printing layer, the multipatch distribution, and the corresponding deposition directions. An asynchronous starting strategy is proposed to prevent the local minimum solutions caused by the concurrent optimization scheme. Several numerical examples were investigated to verify the effectiveness of the proposed method, while satisfactory optimization results have been derived.

Four-dimensional printing using fused-deposition modeling: a review

PurposeThis paper aims to provide a review of four-dimensional (4D) printing using fused-deposition modeling (FDM). 4D printing is an emerging innovation in (three-dimensional) 3D printing that encompasses active materials in the printing process to create not only a 3D object but also a 3D object that can perform an active function. FDM is the most accessible form of 3D printing. By providing a review of 4D printing with FDM, this paper has the potential in educating the many FDM 3D printers in an additional capability with 4D printing.Design/methodology/approachThis is a review paper. The approach was to search for and review peer-reviewed papers and works concerning 4D printing using FDM. With this discussion of the shape memory effect, shape memory polymers and FDM were also made.Findings4D printing has become a burgeoning area in addivitive manufacturing research with many papers being produced within the past 3-5 years. This is especially true for 4D printing using FDM. The key findings from this review show the materials and material composites used for 4D printing with FDM and the limitations with 4D printing with FDM.Research limitations/implicationsLimitations to this paper are with the availability of papers for review. 4D printing is an emerging area of additive manufacturing research. While FDM is a predominant method of 3D printing, it is not a predominant method for 4D printing. This is because of the limitations of FDM, which can only print with thermoplastics. With the popularity of FDM and the emergence of 4D printing, however, this review paper will provide key resources for reference for users that may be interested in 4D printing and have access to a FDM printer.Practical implicationsPractically, FDM is the most popular method for 3D printing. Review of 4D printing using FDM will provide a necessary resource for FDM 3D printing users and researchers with a potential avenue for design, printing, training and actuation of active parts and mechanisms.Social implicationsContinuing with the popularity of FDM among 3D printing methods, a review paper like this can provide an initial and simple step into 4D printing for researchers. From continued research, the potential to engage general audiences becomes more likely, especially a general audience that has FDM printers. An increase in 4D printing could potentially lead to more designs and applications of 4D printed devices in impactful fields, such as biomedical, aerospace and sustainable engineering. Overall, the change and inclusion of technology from 4D printing could have a potential social impact that encourages the design and manufacture of such devices and the treatment of said devices to the public.Originality/valueThere are other 4D printing review papers available, but this paper is the only one that focuses specifically on FDM. Other review papers provide brief commentary on the different processes of 4D printing including FDM. With the specialization of 4D printing using FDM, a more in-depth commentary results in this paper. This will provide many FDM 3D printing users with additional knowledge that can spur more creative research in 4D printing. Further, this paper can provide the impetus for the practical use of 4D printing in more general and educational settings.