Fused Deposition Modeling Printing Research Articles

Optimization of polylactic acid 3D printing parameters based on support vector regression and cuckoo search

Abstract3D printing, also known as additive manufacturing (AM), is evolving from a rapid prototyping tool to a pillar of the Industry 4.0 revolution and widely used in various industries, since it can quickly and efficiently create workpieces with complex structures and integrated functions. After analyzing the 3D printing principle of fused deposition modeling (FDM), this paper proposes a deformation control‐oriented optimization method for process parameters of FDM of the polylactic acid (PLA) materials, based on support vector regression (SVR) and cuckoo search (CS). First, FDM printing principle and its main process parameters were analyzed. Two key parameters, printing temperature and printing speed, were selected for research, with the maximum shrinkage deformation as the workpiece contour accuracy index. Combining Latin Hypercube Sampling (LHS) with Finite Element Analysis (FEA), finite sample sets were generated. Second, learning from the sample data, the SVR surrogate model was built to predict the workpiece contour accuracy, and the nonlinear relationship between FDM process parameters and PLA shrinkage deformation was obtained. Finally, taking the combination of printing temperature and speed as the design variable and minimizing the maximum shrinkage deformation as the optimization objective, the FDM process parameters optimization model was established, and CS was used to search for the optimal parameters combination. Experimental comparison showed that the FEA results and SVR model in this method are correct and effective, and the PLA workpiece shrinkage deformation is smaller under the optimal parameters combination, which effectively improves the shape accuracy of FDM workpieces.Highlights Combining support vector regression (SVR) and cuckoo search (CS) can optimize polymer 3D printing process parameters. Effective finite element model was built for polymer 3D printing. SVR model established by simulation data can predict workpiece deformation. The optimal process parameters were found using CS algorithm.

Chemical characterization of particulates and volatile organic compounds emitted during fused deposition modeling

Additive manufacturing (AM) is largely regarded as an environmentally friendly alternative to traditional manufacturing techniques. However, some studies have pointed out that AM may carry its own environmental implications. It has been reported that high concentrations of ultrafine particle emissions as well as volatile and semi volatile organic compound emissions from the fused deposition modeling (FDM) 3D printing process. The health consequences of exposure to these ultrafine particles and organic compounds are unknown. Determining the chemical composition of the ultrafine particles and the volatile organic compounds is the first step toward understanding potential health risks of FDM process. In this study, we collect air emissions from FDM printing using ABS plastic filament for chemical characterization. Using solid phase microextraction (SPME), compounds in samples are adsorbed or absorbed on a fiber coating and analyzed with gas chromatography mass spectrometry (GC–MS). Several compounds are successfully identified in printer emissions and compared with samples collected from filament wash prior to extrusion. The most predominant compound was styrene, followed by various benzene aromatics, nitrogenated aromatics, and siloxanes. Measurements identifies substantial cross over between compounds found from printer emission and filament wash tests, suggesting that some emissions could possibly be reduced, or in some cases, even eliminated by washing 3D printer filament prior to use.

Investigating capacitive force sensors with 3D printed flexible structures as dielectric layers

The utilization of a three dimension (3D) printing for the fabrication of micro-electromechanical system (MEMS) sensors presents various advantages including low cost, customization, simplicity, and speed. This study involved conducting mechanical and electrical analyses on three types of dielectric layer structures using the finite element method. Capacitive force sensors were produced through 3D printing using fused deposition modeling (FDM). The sensitivity and stiffness of the sensors were determined by measuring their capacitance and displacement changes under force using a self-made measurement system. The experimental results indicate that pre-heating the dielectric layer can reduce the hysteresis effects. In terms of more complex structures, stringing phenomena during the printing process can compromise the reliability of the sensor. A suitable dielectric layer structure can be designed based on the measurement range and sensitivity of the sensor. The results of this study demonstrate the potential for additive manufacturing to replace conventional MEMS processes in sensor production. With the advancement of FDM printing technology, it is increasingly feasible to apply 3D printing technology to sensor manufacturing in the future.

INVESTIGATION OF 3D PRINTING PARAMETERS AFFECTING THE DEVIATION OF PRODUCT BY TAGUCHI METHOD

Fused deposition modeling (FDM) printing method is widely used in the manufacture of technical parts. The article aims to present the survey results of 3D printing parameters (layer height, printing speed, wall thickness) that affect the deviation of product created by the FDM printing method. In this study, 3D scanning technology was applied to measure and check the error of each printed hole. Taguchi method is used in the experiment to design and process data in Minitab software to generate results to evaluate the input values of the investigation. The research results show that the print speed parameter has the highest influence on the error whereas the print wall thickness parameter has the lowest effect. The research results can be used to eliminate the error in making samples by the FDM method.

Modeling of Energy Consumption and Print Time for FDM 3D Printing Using Multilayer Perceptron Network

Given the recognized advantages of additive manufacturing (AM) printing systems in comparison with conventional subtractive manufacturing systems, AM technology has become increasingly adopted in 3D manufacturing, with usage rates increasing dramatically. This strong growth has had a significant and direct impact not only on energy consumption but also on manufacturing time, which in turn has generated significant costs. As a result, this problem has attracted the attention of industry actors and the research community, and several studies have focused on predicting and reducing energy consumption and additive manufacturing time, which has become one of the main objectives of research in this field. However, there is no effective model yet for predicting and optimizing energy consumption and printing time in a fused deposition modeling (FDM) process while taking into account the correct part orientation that minimizes both of these costs. In this paper, a neural-network-based model has been proposed to solve this problem using experimental data from isovolumetrically shaped mechanical parts. The data will serve as the basis for proposing the appropriate model using a specific methodology based on five performance criteria with the following statistical values: R2-squared > 99%, explained variance > 99%, MAE < 0.99%, MSE < 0.02% and RMSE < 1.36%. These values show just how effective the proposed model will be in estimating energy consumption and FDM printing time, taking into account the best choice of part orientation for the lowest cost. This model provides a global understanding of the primary energy and time requirements for manufacturing while also improving the system’s cost efficiency. The results of this work can be extended and applied to other additive manufacturing processes in future work.

Development of a plasma-based 3D printing system for enhancing the biocompatibility of 3D scaffold

Fused deposition modeling (FDM) is a three-dimensional (3D) printing technology typically used in tissue engineering. However, 3D-printed row scaffolds manufactured using material extrusion techniques have low cell affinity on the surface and an insufficient biocompatible environment for desirable tissue regeneration. Thus, in this study, plasma treatment was used to render surface modification for enhancing the biocompatibility of 3D-printed scaffolds. We designed a plasma-based 3D printing system with dual heads comprising a plasma device and a regular 3D FDM printer head for a layer-by-layer nitrogen plasma treatment. Accordingly, the wettability, roughness, and protein adsorption capability of the 3D-printed scaffold significantly increased with the plasma treatment time. Hence, the layer-by-layer plasma-treated (LBLT) scaffold exhibited significantly enhanced cell adhesion and proliferation in an in vitro assay. Furthermore, the LBLT scaffold demonstrated a higher tissue infiltration and lower collagen encapsulation than those demonstrated by a non-plasma-treated scaffold in an in vivo assay. Our approach has great potential for various tissue-engineering applications via the adjustment of gas or precursor levels. In particular, this system can fabricate scaffolds capable of holding a biocompatible surface on an entire 3D-printed strut. Thus, our one-step 3D printing approach is a promising platform to overcome the limitations of current biocompatible 3D scaffold engineering.

Fused deposition modeling of carbon‐reinforced polymer matrix composites: A comprehensive review

AbstractCarbon‐reinforced polymer matrix composites (PMCs) have been thoroughly applied in different fields because of their benefits, such as low specific gravity, corrosion resistance, good electrical conductivity, and robust mechanical properties. Especially, with the emergence of fused deposition modeling (FDM) technology has further promoted the application of such materials in complex structural components. Recently, FDM printing carbon‐reinforced PMCs have become a hot topic in composites research, and many promising results have been achieved around related research. In order to help readers have a comprehensive and systematic understanding of the latest research progress of FDM printing carbon‐reinforced PMCs in terms of material modification, processing, material properties, and application levels, this paper reviews the properties and processes of FDM printed carbon‐reinforced PMCs and their potential applications in aerospace, flexible sensing, electrochemistry, and biomedical fields. The effects of commonly used carbon reinforcing materials on the performance of FDM printed PMCs were contrasted and analyzed. Moreover, the process optimization of printing carbon‐reinforced PMCs was introduced and highlighted. Finally, the current challenges and future research directions of FDM printing carbon‐reinforced PMCs were analyzed and prospected.

Multiobjective optimization of tribological characteristics of 3D printed texture surfaces for ABS and PLA Polymers

In this paper, the 3D-printed textured samples are fabricated using fused deposition modelling (FDM) process for two different polymers such as ABS and PLA. The primary objective of this study is to investigate the influence of printing parameters on the tribological characteristics of 3D-printed textured samples. Here, the four major FDM printing parameters such as layer thickness (LT), nozzle temperature (NT), line width (LW) and printing speed (PS) are considered for the study. Whereas, the tribological characteristics of 3D-printed textured sample such as wear rate and friction coefficient are considered as output responses. The present experimental study is carried out based on the response surface methodology to evaluate the effect of these FDM printing parameters on the tribological characteristics of textured samples. These experimental results show that the line width is the most significant printing parameter followed by layer thickness. Whereas, the printing speed is the third most significant printing parameter. Furthermore, the optimized value of printing parameters for ABS and PLA are evaluated by using grey relational analysis. For the ABS polymer, the optimal value of printing parameters as layer thickness = 0.1 mm, nozzle temperature = 230°C, line width = 0.28 mm and printing speed = 75 mm/s. Whereas, for the PLA, the optimal value of printing parameters are: layer thickness = 0.14 mm, nozzle temperature = 220°C, line width = 0.31 mm, and printing speed = 50 mm/s. In addition, However, the wear rate first decreases with the layer thickness and nozzle temperature and then increases. The wear rate linearly increases with the printing speed.

In-situ measurement of anisotropic Young’s modulus in fused deposition modeling printed cantilevers

In this study, we investigate the effect of fused deposition modeling printing direction on the effective Young’s modulus value of cantilevers. Through finite-element simulations and experiments with seven different dimensions and totaling over 100 cantilevers, we have observed the impact of printing direction on cantilever resonance. Unlike the conventional compressive and tensile stress—strain characterization, observation of the resonance allows for in-situ testing on the final device under test during operation. Initially, we observed the bulk filament modulus to be 4.5 GPa based on the optimal match between experiments and realistic finite element models expressing the internal structures of the longitudinal and transverse printed cantilevers. Then, the effective Young’s modulus of the cantilevers is inferred through sweeping the Young’s modulus that provides the best fit between the experiments, conventional cantilever formulations and finite-element simulations with solid, homogeneous, and isotropic cantilever model. Overall, we observed an average effective Young’s modulus of 3.35 GPa for the cantilevers with longitudinal (along the cantilever axis) deposited filaments and an average effective Young’s Modulus of 2.50 GPa for the transverse (perpendicular to the cantilever axis, along the width dimension) deposited Polylactic acid cantilevers. Eventually, simplified shape outline and effective Young’s modulus for the corresponding printing direction eases the subsequent theoretical and simulation analyses. The presented methodology is also applicable to micrometric and sub-micrometric scale serial manufacturing techniques (i.e. two-photon polymerization) where the laser beams steering direction causes anisotropy in the mechanical properties of the device under test.

Investigation of total skin helical tomotherapy using a 3D-printed total skin bolus

ObjectiveTo investigate the effectiveness of using a 3D-printed total skin bolus in total skin helical tomotherapy for the treatment of mycosis fungoides.Materials and methodsA 65-year-old female patient with a 3-year history of mycosis fungoides underwent treatment using an in-house desktop fused deposition modelling printer to create a total skin bolus made of a 5-mm-thick flexible material, which increased the skin dose through dose building. The patient's scan was segmented into upper and lower sections, with the division line placed 10 cm above the patella. The prescription was to deliver 24 Gy over 24 fractions, given 5 times per week. The plan parameters consisted of a field width of 5 cm, pitch of 0.287 and modulation factor of 3. The complete block was placed 4 cm away from the planned target region to reduce the area of the internal organs at risk, especially the bone marrow. Dose delivery accuracy was verified using point dose verification with a "Cheese" phantom (Gammex RMI, Middleton, WI), 3D plane dose verification with ArcCHECK (Model 1220, Sun Nuclear, Melbourne, FL), and multipoint film dose verification. Megavoltage computed tomography guidance was also utilized to ensure the accuracy of the setup and treatment.ResultsA 5-mm-thick 3D-printed suit was used as a bolus to achieve a target volume coverage of 95% of the prescribed dose. The conformity index and homogeneity index of the lower segment were slightly better than those of the upper segment. As the distance from the skin increased, the dose to the bone marrow gradually decreased, and the dose to other organs at risk remained within clinical requirements. The point dose verification deviation was less than 1%, the 3D plane dose verification was greater than 90%, and the multipoint film dose verification was less than 3%, all of which confirmed the accuracy of the delivered dose. The total treatment time was approximately 1.5 h, which included 0.5 h of wearing the 3D-printed suit and 1 h with the beam on. Patients only experienced mild fatigue, nausea or vomiting, low-grade fever, and grade III bone marrow suppression.ConclusionThe use of a 3D-printed suit for total skin helical tomotherapy can result in a uniform dose distribution, short treatment time, simple implementation process, good clinical outcomes, and low toxicity. This study presents an alternative treatment approach that can potentially yield improved clinical outcomes for mycosis fungoides.

Antibacterial Efficacy of Non-Copper Polymer Based Composite Enhanced with Metallic Particles Using Fused Deposition Modeling

The aim of this experimental investigation is to assess the antibacterial resistance of a biodegradable Polylactic acid (PLA) based composite material enriched with non-copper metallic particles, notably Stainless Steel, and Aluminum as alternatives to copper. The composite materials were processed using additive manufacturing technology using commercial fused deposition modeling printers to produce samples for antibacterial testing. The antibacterial materials were assessed according to international standards to evaluate the antibacterial efficacy at different time intervals. It has been disclosed that the biodegradable PLA composite enhanced with Stainless Steel or Aluminum demonstrated an excellent resistance against distinct kinds of bacteria through the observed significant reduction in the bacteria levels.

Novel Rhinological Application of Polylactic Acid-An In Vitro Study.

A novel approach to the treatment of sinusitis is the use of nasal stents. The stent is loaded with a corticosteroid, which prevents complications in the wound-healing process. The design is such that it will prevent the sinus from closing again. The stent is 3D printed using a fused deposition modeling printer, which enhances the customization. The polymer utilized for the purpose of 3D printing is polylactic acid (PLA). The compatibility between the drugs and polymers is confirmed by FT-IR and DSC. The drug is loaded onto the polymer by soaking the stent in the drug's solvent, known as the solvent casting method. Using this method, approximately 68% of drug loading is found to be achieved onto the PLA filaments, and a total of 72.8% of drug loading is obtained in terms of the 3D-printed stent. Drug loading is confirmed by the morphological characteristics of the stent by SEM, where the loaded drug is clearly visible as white specks on the surface of the stent. Drug release characterization is conducted by dissolution studies, which also confirm drug loading. The dissolution studies show that the release of drugs from the stent is constant and not erratic. Biodegradation studies were conducted after increasing the rate of degradation of PLA by soaking it in PBS for a predetermined duration of time. The mechanical properties of the stent, such as stress factor and maximum displacement, are discussed. The stent has a hairpin-like mechanism for opening inside the nasal cavity.

Application of xanthan and locust bean gum mix or sorbitol in the jelly formulation to improved jelly 3D printing using a fused deposition modeling printer.

This study examined the impacts of applying a xanthan and locust bean gum mix or sorbitol to a jelly formulation on the rheological parameters necessary for 3D printing a jelly applying the fused deposition modeling method. A jelly formulation was fortified with a gum mix (xanthan gum:locust bean gum = 0.625:0.375) at 1% (w/w), or added with sorbitol instead of sugar. Both treatments increased the values of storage modulus and yield stress, related to fidelity and shape retention, and adding the gum mix, in particular, increased the gel strength. Applying these treatments to the formulation that lacks the rheological parameters and gel strength required for 3D printing changed those values in a direction fulfilling the material requirements. This research confirmed that the application of xanthan and locust bean gum mix or sorbitol could adjust the properties of materials used in 3D printing for improved printability.

Veering to a Continuous Platform of Fused Deposition Modeling Based 3D Printing for Pharmaceutical Dosage Forms: Understanding the Effect of Layer Orientation on Formulation Performance.

Three-dimensional (3D) printing of pharmaceuticals has been centered around the idea of personalized patient-based 'on-demand' medication. Fused deposition modeling (FDM)-based 3D printing processes provide the capability to create complex geometrical dosage forms. However, the current FDM-based processes are associated with printing lag time and manual interventions. The current study tried to resolve this issue by utilizing the dynamic z-axis to continuously print drug-loaded printlets. Fenofibrate (FNB) was formulated with hydroxypropyl methylcellulose (HPMC AS LG) into an amorphous solid dispersion using the hot-melt extrusion (HME) process. Thermal and solid-state analyses were used to confirm the amorphous state of the drug in both polymeric filaments and printlets. Printlets with a 25, 50, and 75% infill density were printed using the two printing systems, i.e., continuous, and conventional batch FDM printing methods. Differences between the two methods were observed in the breaking force required to break the printlets, and these differences reduced as the infill density went up. The effect on in vitro release was significant at lower infill densities but reduced at higher infill densities. The results obtained from this study can be used to understand the formulation and process control strategies when switching from conventional FDM to the continuous printing of 3D-printed dosage forms.

Influence of Magnet Particle Shape on Magnetic and Environmental Stability of FDM Polymer-Bonded Magnets.

In this research, the feasibility of additive manufacturing of permanent bonded magnets using fused deposition modelling (FDM) technology was investigated. The study employed polyamide 12 (PA12) as the polymer matrix and melt-spun and gas-atomized Nd-Fe-B powders as magnetic fillers. The effect of the magnetic particle shape and the filler fraction on the magnetic properties and environmental stability of polymer-bonded magnets (PBMs) was investigated. It was found that filaments for FDM made with gas-atomized magnetic particles were easier to print due to their superior flowability. As a result, the printed samples exhibited higher density and lower porosity when compared to those made with melt-spun powders. Magnets with gas-atomized powders and a filler loading of 93 wt.% showed a remanence (Br) of 426 mT, coercivity (Hci) of 721 kA/m, and energy product (BHmax) of 29 kJ/m3, while melt-spun magnets with the same filler loading had a remanence of 456 mT, coercivity of 713 kA/m, and energy product of 35 kJ/m3. The study further demonstrated the exceptional corrosion resistance and thermal stability of FDM-printed magnets, with less than 5% irreversible flux loss when exposed to hot water or air at 85 °C for over 1000 h. These findings highlight the potential of FDM printing for producing high-performance magnets and the versatility of this manufacturing method for various applications.

Supramolecular Soft Material Enabled by Metal Coordination and Hydrogen Bonding: Stretchability, Self-Healing, Impact Resistance, 3D Printing, and Motion Monitoring.

Metal coordination can significantly improve the macroscopic performance of many materials by enhancing their dynamic features. In this study, two supramolecular interactions, Fe3+ -carboxylic acid coordination, and structural water-induced hydrogen bonding, into an artificial polymerwereintroduced. Various attractive features, including flexibility and stretchability, are achieved because of the bulk state and dynamic hydrogen bonds of poly(thioctic acid-water) (poly[TA-H]). These unique features are considerably enhanced after the incorporation of Fe3+ cations into poly[TA-H] because metal coordination increased the mobility of the poly[TA-H] chains. Thus, the poly(thioctic acid-water-metal) (poly[TA-HM]) copolymer exhibited better flexibility and stretchability. Moreover, notable underwater/low-temperature self-healing capacity is obtained via the synergistic effect of the metal and hydrogen bonding. Most of the impact energy is quickly absorbed by poly[TA-H] or poly[TA-HM] and effectively and rapidly dissipated via reversible debonding/bonding via the interactions between the metal and hydrogen. Macroscopic plastic deformation or structural failure is not observed during high-speed (50-70ms-1 ) impact experiments or high-altitude (90m) falling tests. Furthermore, poly[TA-HM] displayed good thermal molding properties, which enabled its processing via 3D fused deposition modeling printing. Poly[TA-HM] also showed considerable effectiveness for monitoring complicated, dynamic, and irregular biological activities owing to its highly pressure-sensitive nature.

Copper Composites and Laser Sintering: Novel Hybridization Method for 3D Printed Electronics

AbstractAdditive manufacturing of electronic devices is challenging because plastics and metals, which are both required as insulator and conductor, respectively, have very distinct thermal properties. Despite significant research efforts, the currently available electronic‐printing methods are still limited by low printing speeds and high manufacturing costs. In this work, a hybrid printing method is proposed that combines fused deposition modeling (FDM) with laser sintering to print thermoplastics and copper in a single process. A copper and copper‐oxide composite filament is developed that is compatible with FDM printing. The composite undergoes in situ reduction under laser exposure and produces a highly conductive copper network. Using the home‐developed 3D printer, 3D conductive vias embedded in thermoplastic dielectric are demonstrated. The printed copper electrodes have low resistivity of 4 × 10−4 Ω cm and are compatible with soldering. This novel metal‐deposition approach and setup prove a novel concept for developing modern electronics using additive manufacturing.

Potential Construction Applications of Sustainable 3D Printed Elements Made from Plastic Waste

Construction projects are often challenged by tight budgets and limited resources. Contractors are looking for ways to become competitive by using methods and materials that are sustainable and cost-effective. Using sustainable 3D printing to produce cost-effective construction elements is becoming a feasible option to make contractors more competitive locally and globally. Along this line, contractors are attempting to improve production skills to satisfy certain specifications and standards while keeping costs within competitive ranges. The aim of this research is to investigate the production process capability of 3D printers using fused deposition modelling (FDM) to produce 3D-printed sustainable parts made from plastic waste for the use in the construction of buildings with different infill structures and internal designs. The production capabilities and requirements of FDM printers were first examined and possible applications in construction are then presented. The outcome of this study indicates that 3D-printers can be used to produce parts made from plastic waste using FDM printers. These parts are sustainable and less expensive as compared to some traditional non-load bearing construction elements such as lightweight concrete hollow blocks and lightweight concrete bricks since they are less expensive and have higher compressive strength. However, it is not feasible to use 3D printed material from plastic waste as an alternative for gypsum board drywalls since it is more expensive; however, it might be considered as an alternative since it provides a higher compressive strength.

Shear Test Characterization of 3D Printed Polyamide Reinforced Carbon Fiber Composites

The issue of delamination occurring on PACF materials is a structural application failure due to poor mechanical strength. The bonding process of composite materials between layers using fused deposition modeling (FDM) printing affects the tensile strength of the material. The main objective of this study was to study the shear strength of polyamide reinforced carbon composite (PACF) materials by using shear test method and to study the effect of fractured or delamination surfaces during shear testing. In this study, PACF material was printed using FDM technique through Ultimate S3 machine. A total of 20 printed PACF specimens underwent a semi-overlapping adhesion process using Loctite E-20HP epoxy adhesive which required curing for 24 hours at room temperature. Shear test methods were performed on PACF composite specimens using Universal Testing Machine. Furthermore, PACF samples were conducted experiments to determine the physical properties of the composites of the material as well as Scanning Electron Microscopy (SEM) experiments through fractured or eliminated surfaces. Based on the results obtained, the PACF material has a high shear tensile strength compared to that of epoxy adhesives with an average rate of 1.6 MPa respectively. This is may due to the low curing temperature and the thick epoxy layer. It was observed that the FDM printing method produces a porous print layer that can facilitate delamination to occur.

Sandwiching textiles with FDM Printing

3D printing on textile fabrics has been investigated intensively during the last years. A critical factor is the adhesion between the printed polymer and the textile fabric, limiting the potential areas of application. Especially safety-related applications, e.g. stab-resistant textile/polymer composites, need to show reliable adhesion between both components to serve their purpose. Here we investigate the possibility of sandwiching textiles between 3D-printed layers, produced by fused deposition modeling (FDM). We show that adding nubs to the lower 3D-printed layers stabilizes the inner textile fabric and suggest future constructive improvements to further enhance the textile-polymer connection.