Infill Density Research Articles

Maximizing performance and efficiency in 3D printing of polylactic acid biomaterials: Unveiling of microstructural morphology, and implications of process parameters and modeling of the mechanical strength, surface roughness, print time, and print energy for fused filament fabricated (FFF) bioparts

Medical stents, artificial teeth, and grafts are just some of the many applications for additive manufacturing techniques like bio-degradable polylactic acid 3D printing. However, there are drawbacks associated with fused filament fabrication-fabricated objects, including poor surface quality, insufficient mechanical strength, and a lengthy construction time for even a relatively small object. Thus, this study aims to identify the finest polylactic acid 3D printing parameters to maximize print quality while minimizing energy use, print time, flexural and tensile strengths, average surface roughness, and print time, respectively. Specifically, the infill density, printing speed, and layer thickness are all variables that were selected. A full-central-composite design generated 20 samples to test the prediction models' experimental procedures. Validation trial tests were used to show that the experimental findings agreed with the predictions, and analysis of variance was used to verify the importance of the performance characteristics (ANOVA). At layer thickness = 0.26 mm, infill density = 84 %, and print speed = 68.87 mm/s, the following optimized values were measured for PLA: flexural strength = 70.1 MPa, tensile strength = 39.2 MPa, minimum surface roughness = 7.8 μm, print time = 47 min, and print energy = 0.18 kwh. Firms and clinicians may benefit from utilizing the developed, model to better predict the required surface characteristic for various aspects afore trials.

Optimization of fused deposition modeling parameters to fabricate morphogenesis light weight structure with high tensile and compression strength

Fused deposition modeling (FDM) is a contemporary approach that can produce simple and complex physical models, prototype tools, and functional components. However, the challenge is choosing the right parameters, which are essential to printing a high-quality Additive Manufactured (AM) structure with acceptable mechanical attributes, like mechanical strength. In the additive manufacturing technique, fabricating a lightweight structure without compromising the weight and shape is very difficult because the significant parameter is infill density (D) %, which is directly proportional to the strength and inversely proportional to the weight. In this research based on morphogenesis, the infill density is varied at different locations wherever it is needed to print a lightweight, high-strength structure. Parameters Layer Thickness (LT), Shell Thickness (ST), and D were chosen, and experiments were conducted as per Central Composite Design (CCD). Tensile Strength (TS) and Compression Strength (CS) samples were printed with PLA and tested. The results were used to develop a multi-objective function. To predict maximum TS and CS without compromising the weight, Particle Swarm Optimization (PSO) and Response Surface Methodology (RSM) techniques were used to solve the multi-objective function. PSO predicts that the optimum printing parameter values for achieving a lightweight, high-strength structure are LT of 0.17 mm, ST of 0.91 mm, and D of 11.3%. These predicted results were confirmed through experiments.

Effect of Process Parameters on the Hardness of 3D-printed Thermoplastic Polyurethane that Includes Foaming Agent

Recent progress in Material Extrusion-based Additive Manufacturing (MEX) has introduced active foaming agents in filaments composition, thus allowing for the tuning, by various process parameters, the hardness and the mechanical behavior of 3D-printed parts. In case of thermoplastic polyurethane (TPU) filaments, these advances significantly broaden the range of applications, particularly in the domains of comfort and orthotics (wrist-hand orthoses, insoles), offering the dual benefits of design flexibility inherent in MEX and the comfort of lightweight and customizable structures. However, the field is still in its early stages, with only a limited number of research efforts dedicated to characterizing these novel materials. In this context, this study is focused on determining the influence of printing temperature (190�C, 220�C, 240�C), infill density (25%, 35%, 45%) and infill pattern (honeycomb, gyroid) over the hardness of cylindrical specimens made of Colorfabb varioShore TPU. A comprehensive methodology of calibration is also presented as mandatory for obtaining good quality and accurate products by establishing correlations between flow rate and printing temperatures. The findings showed that the printing temperature is the most relevant factor impacting the hardness of varioShore TPU prints. At a printing temperature of 190�C, which corresponds to less foamed prints, the honeycomb infill yielded higher hardness compared to the gyroid infill, but the difference was not significant. Also, at 220�C and 240�C, the mean values of hardness remain relatively consistent, regardless of infill density and pattern.

Optimizing the printing parameters for dimensional accuracy of distal femur bone by using Taguchi’s method

BackgroundFused deposition modelling (FDM) is a popular additive manufacturing technique with capability of producing complex and integrate shapes. One of the critical aspects of FDM is the dimensional accuracy of 3D (three-dimension) printed model, especially in medical science applications, as proper fit and function with human body can prevent patient’s discomfort, complication or even harm.ObjectiveIn this research work, the optimisation of print parameters: layer height, nozzle temperature, printing speed, infill pattern and infill density for improving the dimensional accuracy of distal femur bone, an irregular and complex shaped geometry is carried out using Taguchi’s method and to study its influence using ANOVA (analysis of variance).Methodology3D CAD (computer-aided design) model of the distal femur bone is generated from a CT (computerized tomography) scan using 3D slicer and its associated errors are corrected using Ansys SpaceClaim. The model is prepared for printing using Ultimaker Cura as per L16 orthogonal array experimental layout where TEA (trans epicondylar axis), which is the distance between the most prominent point of the lateral and medial epicondyle, is set at 45° from X-axis in XY plane, i.e. diagonally on the plane of printing bed. It is then printed with PLA (polylactic acid) filament. Length along TEA is compared accordingly with 3D CAD model. Taguchi’s method of ‘smaller the better’ is applied for reducing deviation. Further, ANOVA analysis is done on the data set and a linear regression model is also developed.ResultThrough Taguchi’s method, the optimum parameters were found to be triangle for infill pattern, 200 °C for nozzle temperature, 30 mm/s for nozzle speed, 0.1 mm for layer height and 40% for infill density. ANOVA analysis shows that all parameters contribute significantly with layer height being the most influential parameter, followed by infill pattern, nozzle speed, nozzle temperature and infill density. Mathematical model through multiple linear regression method was developed with determination of coefficient value of 96.91% and standard residual value is within the acceptable range of ± 2 indicating that there is no outliner in the data.

Mechanical properties of laminate materials based on polylactic acid and polyvinyl chloride meshes as reinforcement

The 3D printing parameters are known to have a significant impact on manufactured parts, and the layered morphology of these parts makes mechanical design analysis for engineering applications difficult. In this work, the tensile strengths and microhardness of 3D printed polylactic acid (PLA) specimens with different orientations and numbers of individual layers of mesh material (polyvinyl chloride – PVC) were investigated as a laminate composite. Composite specimens were obtained using 3D printing via fused deposition modelling (FDM). Moreover, the influence of printing parameters (i.e. infill density and layer height) and the number and orientation of reinforced meshes on the mechanical response was investigated. Fracture strength of PLA/PVC laminate composites ranges from 31.30 MPa (3 PVC mesh layers; mesh height position: 25 %│50 %│75 %; infill density: 60 %; PVC mesh orientation: 90°│45°│90°; layer height: 0.2 mm) to 18.62 MPa (without PVC mesh; infill density: 30 %; layer height: 0.1 mm) demonstrating a significant impact of the number of the PVC mesh layers, infill density of PLA and layer height on the final mechanical parameters of printing PLA/PVC elements. The surface hardness at the micro load level showed that the number of reinforcement layers affects the microhardness value, as well as material filling and mesh orientation. The specimen with the following parameters gave the best results: layer height: 0.2 mm; 3 PVC mesh layers; infill density: 60 %; PVC mesh orientation: 90°│45°│90°. The average hardness values for one layer and three layers of mesh were in accordance with tensile test results.

Comparative Analysis of Energy Consumption and Carbon Footprint of Additively Manufactured Solid and Lattice structure Tensile Specimens

Manufacturing significantly contributes to global warming due to its substantial carbon emissions. United Nations sustainable development goals support the reduction of carbon emissions in the manufacturing sector, which can be accomplished by making the manufacturing process sustainable with a minimal carbon footprint. This is also appropriate for novel manufacturing processes such as additive manufacturing. This study introduces the investigation of the additively manufactured specimen. Prior research delves into examining the impact on the energy consumption of solid specimens under distinct printing process parameters. Nonetheless, the influence of electrical energy consumption and total carbon footprint for the additively manufactured solid and lattice structure has yet to be investigated. The current study fills the research gap by assessing layer thickness and infill density on both specimens’ electrical energy consumption and total carbon footprint. The presented study offers insight into the impact of layer thickness and infill density for the solid and lattice structure specimens and their comparison of electrical energy consumption and total carbon footprints. The results demonstrated that a rise in an infill density directly correlates with increased energy consumption and carbon footprints. However, rising layer thickness resulted in a reduction in both power consumption and carbon footprints. Furthermore, it was observed that the triangular, octagonal, and hexagonal cellular structures manifest higher power consumption when the infill density is set at 50% and 80%, respectively. Moreover, when assessing a solid specimen at 100% infill density, the total carbon footprint exhibits increases of 12%, 21%, 23%, and 41% in comparison to triangular, octagonal, hexagonal, and square lattice structures, respectively.

Experimental investigations and numerical simulations of lattice structures obtained by additive manufacturing

In this study, both experimental and numerical investigations are carried out on samples fabricated by additive manufacturing (AM). The determination of stress distribution in parts obtained by AM, even for simple tensile test, is complicated because it is largely influenced by many manufacturing parameters as the adopted infill pattern, the infill orientation and the infill density. Firstly, the material parameters of the fused filament PLA and tensile specimens made by the AM with an infill grid pattern with density of 100% are experimentally determined. Then, the effect of the infill orientation with an infill density of 40% on the tensile stress state is experimentally and numerically investigated. By synthesizing these results, a comprehensive understanding of stress distribution in AM-produced components is achieved. The obtained anisotropic mechanical parameters are used to simulate compression of a flat-ring part.

Assessing quality in extrusion based additive manufacturing technologies

Quality is a magic word that has fascinated the people since the early days of civilization and today, quality is the only mantra to survive. Quality is the only relevant attribute associated with product and processes that makes any technology in-demand. The quality of the parts produced by Additive Manufacturing (AM) Technologies depends on many factors, like print speed, nozzle temperature etc. The aim of this work is the identification of influence factors that affect the performance measures of extrusion based Additive Manufacturing (AM) technologies, namely, Fused Deposition Modelling (FDM). These processes can be characterized by a set of influence factors, like print speed, infill density, temperature; layer thickness and build orientation are responsible for quality of the product. In this work, Grey relational Analysis (GRA) is employed. GRA is a method which enables determination of the relational degree of every factor in the system. The method can be used for systems that are not completely described and with relatively few available data. Reliable technique of optimization GRA is clubbed with another established technique; called Interrelation ship Diagram (ID), to identify and optimize the influence factors, that yields highest performance characteristics. Manufacturing Combinations are evaluated against performance measures. In the earlier research, the authors have applied same tool, GRA clubbed with 7QC tools, to evaluate extrinsic and intrinsic qualities of the parts produced by FDM, In this research, the entire focus is paid to the intrinsic properties of the parts produced by FDM. This research will have a greater impact on the quality of the parts produced by the FDM.

Investigation of Tensile Properties of FDM-Printed Reclaimed Carbon Fiber Reinforced Reclaimed Polyamide-6 Composites (rCF/rPA) via Various Densities of Infill Patterns

This work determined the effect of different infill patterns with various infill densities on the tensile properties of FDM-printed reclaimed carbon fiber reinforced reclaimed polyamide-6 (rCF/rPA) composites. The rCFs were derived from recycled carbon fiber composite wastes by pyrolysis, while the rPA recyclates were obtained by mechanical recovery of end-of-life (EoL) nylon fishnets. The comparison between honeycomb and triangular infill patterns within rCF/rPA coupons via the FDM recycling was performed under the various relative densities of 10%, 30%, 50%, 70%, and 90%. The best performance of rCF/rPA coupons occurred in honeycomb infill patterns with 90% relative infill densities. The tensile strength and modulus of those specimens were 76.5 GPa ± 3.5 MPa and 4.8 GPa ± 0.1 GPa, respectively.

Throughput scaling and thermomechanical behaviour in multiplexed fused filament fabrication

Multiplexed Fused Filament Fabrication (MF3) combines a dynamic extrusion-based toolpath with a multi-extruder-single-gantry machine tool architecture to increase printing speed without sacrificing geometric capabilities or increasing hardware complexity. This work establishes a novel capability for geometrically generalizable synthesis of MF3 toolpaths and creates a new thermal model that incorporates the unique nature of material deposition. It is shown that MF3 can increase throughput by an order of magnitude or more via the atypical and nonlinear effects of part size, infill density and extruder spacing. Further, the unusual temperature history in MF3 is found to enhance the part's mechanical properties.

Investigating the impact of infill patterns on shape memory effect in material extrusion

Extensive research has been conducted on Shape Memory Polymers (SMPs) for their potential application in additive manufacturing. The Shape Memory Effect (SME), a key attribute of SMPs, enables 3D-printed objects to alter their shape in response to external stimuli. Several methods for programming SMEs have been explored, such as modifying printing parameters like infill patterns or density. However, incorporating SMPs as substitutes for conventional functional components has been challenging due to grafting difficulties and the limited reliability of SMEs. In this research, the influence of internal structures on SMEs is examined by comparing the full shape recovery period. This investigation has revealed the impact of different infill structures on SMEs and uncovered a complex shape recovery pattern termed multi-phased SME. This occurs when straight infill structures are nearly parallel along the length of a cuboid specimen that has been programmed to form a 90° curve. This finding enhances the creation of complex shape recovery behaviours by simply modifying printing parameters and is applicable to a variety of SMPs.

Influence of infill patterns and densities on the fatigue performance and fracture behavior of 3D-printed carbon fiber-reinforced PLA composites

<p>This paper studied the mechanical properties of carbon fiber-reinforced polylactic acid (CF-PLA) samples manufactured with three different 3D-printed patterns: gyroid, tri-hexagon, and triangular. Filler content was generated in the samples at infill ratios of 30%, 60%, and 90%. Conventional tensile, flexural, impact, and fatigue tests were conducted to investigate the mechanical properties. It was found that the gyroid infill pattern enhanced performance, exhibiting tensile strength and modulus of elasticity up to 63% and 13% greater, respectively, than the tri-hexagon pattern at a 90% infill ratio. The fatigue life improvement was 113% compared with the tri-hexagon pattern. The tensile strength and modulus of elasticity increased up to 35% and 40% after including carbon fibers. The increase in flexural modulus was 30% compared to the triangular pattern, whereas impact energy absorption reached the best result with the triangular pattern, up to 89% more than the gyroid pattern. These results elucidate the optimization of infill patterns and ratios together with carbon fiber reinforcement for the development of CF-PLA components as a high-performance 3D printing solution for a wide range of engineering applications.</p>

Mechanical properties and failure analysis of PLA/copper composites fabricated by fused deposition modelling

The Fused Deposition Modelling process is an additive manufacturing process that is influenced by numerous parameters that affect the strength of the components. This paper article is dedicated to the study of the effects of Fused Deposition Modelling parameters on the strength of PLA/Copper infill composites. The influence on tensile, impact and flexural strength was investigated by varying the process parameters. The printer properties, i.e. the Nozzle Temperature and Printing speed, and the processing parameters, i.e. the Layer Thickness and the density of the infill are the most important parameters considered in this study. Mathematical models were developed to predict the strength of the composites as the process parameters were varied. The strength of the composites decreased with increasing layer thickness and printing speed. On the other hand, in the strength of the composites increased when the nozzle temperature and the density of the infill were increased. The composite samples were subjected to failure analysis to determine the fracture mechanisms. Both brittle and ductile failure mechanisms were observed in the samples, which are influenced by the process parameters affecting the layered composite and porosity.

Development of Space-Borne Antenna Reflector via 3D Printing

The growing necessity of large aperture-based structures for many aerospace applications emphasizes the need to deploy large antenna structures in space. The space antennas should be light in weight and have low stowage volume, with efficient membrane packaging. The concept of additive manufacturing has been introduced to reduce weight as well as cost. In this paper, a comparative study has been done to analyze the advancement made in reducing weight with adequate strength. Based on the study, the main objectives are to develop a 3D-printed spherical reflector model with high specific strength and to assess the consistency of the model's shape. For determining the specific strength, tensile testing is performed on four different infill densities (20%, 40%, 60%, and 80%) with a grid infill pattern. It was observed that the specimen with 80% infill density has the highest tensile strength, 36.56 MPa, which is 23.51% more than 20% infill. However, the specimen with 20% infill density has the highest specific strength of 19.323 GPa/kg among the four specimens, which is approximately 64.64% higher than the 100% infill density. As a result of the testing, the spherical reflector model is 3D printed with 20% infill density, and it was found that the model achieves its shape stability and shape consistency with adequate specific strength.

Optimizing PEEK impact strength through multi-objective FDM 3D printing

Thermoplastic materials such as Polylactic acid, Acrylonitrile Butadiene Styrene, Polyethylene terephthalate glycol, Nylon, and Thermoplastic polyurethane are favoured in Fused deposition modeling 3D printing due to their cost-effectiveness and versatile properties. However, with the introduction of high grade thermoplastic material poses compatibility challenges with existing machines and processes, impeding widespread adoption in FDM 3D printing. Incorporating new materials into 3D printing requires adjustments to hardware, software, and settings, leading to potential expenses and time investments. Maintaining quality control and consistency becomes complex as each material demands specific parameters and processing conditions. This variability hinders achieving consistent part quality in 3D printing. Moreover, achieving optimal FDM parameters for high-grade polymers (HGPs) like Polyether ether ketone (PEEK) is a challenge due to the distinctive nature of the property, requiring specialized careful considerations during its optimization process. The considerable thermal gradient and heat distribution during printing can lead to residual stresses and deformations, significantly affecting the quality and, in particular, its impact strength. This article optimizes an industry grade 3D printing PEEK based on the limited number of process parameters, namely, build orientation, in-fill density and chamber temperature. Further, the research tries to derive a predictive model for Impact Strength (IS), which is an important consideration for the 3D printed object. In this article, along with the Impact Strength, Printing Time and Material Usage are also studied to find empirical evidence of association between these output variables or response variables. The result indicates that there is a positive significant correlation or association between them. When utilizing a specific parameter setup, the resulting IS of 86.5 kJ/m², a print time of 89 minutes, and a material usage of 3.26 grams are achieved. Notably, there is a measurable reduction of 9.18% in printing time and a 11.66% decrease in material usage when the print density is set to 100% to optimize impact strength. This optimization approach proves the use of composite desirability is a better approach where multiple objectives need to be achieved. The proposed regression model predicts the impact strength with coefficient of determination value more than 50%.

Analysis of the Influence of Structural Characteristics on the Tensile Properties of Fused Filament Fabricated ABS Polymer Using Central Composite Design

This study presents an investigation of the effects of structural characteristics, such as the layer height, infill density, top/bottom layer line directions and infill pattern, on the structural efficiency of Acrylonitrile Butadiene Styrene (ABS)-based specimens. The Fused Filament Fabrication (FFF) technique was utilized for the specimen fabrication, and the Ultimate Tensile Strength (UTS) and Strength-to-Mass (S/M) ratio were examined. The tests were planned according to the Central Composite Design (CCD), and an empirical model for each response was developed, with respect to the applied factors and their interactions. The analysis revealed that the characteristics with the strongest influence on the UTS and the S/M ratio were the infill and the layer height, respectively. Moreover, it was observed that the honeycomb structure contributed to the highest UTS compared to the other patterns. Finally, an optimization analysis based on the desirability function was performed, highlighting the combination of a 0.3 mm layer, 21.81% and 76.36% infill, 0° direction and the honeycomb pattern as the optimal for maximizing both UTS and S/M ratio under different desirability.

INFLUENCE OF FUSED DEPOSITION MODELING REGIME PARAMETERS ON MANUFACTURING TIME OF UAV PARTS

Purpose. Investigate the regularities of FDM process parameters influence on the manufacturing time of parts.
 Research methods. The samples for research were produced by the FDM method on a Profi+midi 3D printer. Slic3rPE software were used for CAD model slicing and G-code preparation. The samples were printed using ABS+ filament. The STATISTICA software package was used for statistical processing of the results.
 Results. The influence of different combinations of FDM process parameters (printing speed, layer height, infill geometry, infill density) on the manufacturing time of products was examined. The main factors affecting the manufacturing time were established: printing speed, layer height, infill density and the interaction of these factors
 Scientific novelty. Analysis of the manufacturing time dependence on the layer height and the infill density showed that when selecting a layer height of 0.15 mm and 25 % infill and a layer height of 0.3 mm and 100% infill, the manufacturing time turned out to be nearly identical. It can be concluded that for a lower layer height, increasing the infill density significantly increased the manufacturing time, while setting a higher layer and increasing the infill density led to a small increase in the manufacturing time. It was found that for a layer height of 0.15 mm at a printing speed of 40 mm/s, the manufacturing time significantly increased compared to a printing speed of 80 mm/s, while when selecting a layer height of 0.3 mm, the manufacturing time is less and a decrease in the printing speed led to a small increase of manufacturing time compared to a layer height of 0.15 mm. It was established that an increase in printing speed led to a decrease in manufacturing time and an increase in infill density led to an increase in manufacturing time. Thus, the manufacturing time at a printing speed of 40 mm/s and infill density of 25 % differed slightly from a printing speed of 80 mm/s and infill density of 100 %.
 Practical value. A regression equation was obtained which allowed predicting the influence of the FDM process parameters on the manufacturing time of parts.

Optimizing printing parameters for enhanced mechanical properties of 3D printed PLA octet lattice structures

This study explores the impact of printing parameters on the mechanical properties of 3D printed octet lattice structures using PLA material. Focused on optimizing layer height, print speed, and infill density, the study employed Taguchi methodology. Compressive strength and strength per mass were the key metrics analyzed. The optimized parameters, determined as 0.2 mm layer height, 90 mm/s print speed, and 100% infill density, significantly enhanced compressive strength. Infill density emerged as the most influential factor, contributing to 82.74% of the overall variation. A robust predictive model was developed, achieving a 92.06% accuracy in estimating compressive strength per mass values. These findings provide crucial guidelines for manufacturing high-strength, lightweight PLA octet lattice structures, vital in industries like aerospace and automotive. This study advances additive manufacturing, opening avenues for further research in diverse lattice structures and materials.

A review on exploration of the mechanical characteristics of 3D-printed biocomposites fabricated by fused deposition modelling (FDM)

PurposeThis paper aims to investigate the current state of biocomposites used in fused deposition modelling (FDM) with a focus on their mechanical characteristics.Design/methodology/approachThe study presents a variety of biocomposite materials that have been used in filaments for 3D printing by different researchers. The process of making filaments is then described, followed by a discussion of the process parameters associated with the FDM.FindingsTo achieve better mechanical properties of 3D-printed parts, it is essential to optimize the process parameters of FDM while considering the characteristics of the biocomposite material. Polylactic acid is considered the most promising matrix material due to its biodegradability and lower cost. Moreover, the use of natural fibres like hemp, flax and sugarcane bagasse as reinforcement to the polymer in FDM filaments improves the mechanical performance of printed parts.Originality/valueThe paper discusses the influence of critical process parameters of FDM like raster angle, layer thickness, infill density, infill pattern and extruder temperature on the mechanical properties of 3D-printed biocomposite.

Design and Optimization of 4D Printed Carbon Fiber Reinforced Poly Lactic Acid Parts Using Fused Deposition Modeling for Shape Memory Applications: A Taguchi Approach

The manufacturing industry has witnessed substantial interest in the advancement of 4D printing technology in recent years. This technology has enabled the production of complex structures with enhanced functionality and adaptability. Fused Deposition Modeling (FDM) has become a preferred technique for 4D printing due to its ease of use, affordability, and versatile nature. To achieve efficient and effective 4D printing, the process parameters must be optimised to ensure the desired shape recovery behaviour of the printed parts. The main objective of this study is to optimize the process parameters for the production of 4D printed components using FDM technology and Carbon Fiber reinforced Poly Lactic Acid (CF/PLA) Shape Memory Polymer Composites (SMPCs). This study examines the shape recovery properties of the printed components by modifying the process parameters, including Infill Density (ID), Geometrical Thickness (GT), and Bending Angle (BA), through the implementation of Design of Experiments (DOE) L9 Orthogonal Array (OA). Utilizing Analysis of Variance (ANOVA) to determine the significant factors and their optimum levels, the process parameters are statistically analysed. The results indicate that ID and GT are the statistically significant parameters, and the optimum levels for parameters includes 20% ID, 1.5mm GT, and 300 BA led to faster shape recovery. This study demonstrates the effectiveness of the Taguchi approach in the design and optimization of the process parameters for 4D printed parts using FDM.