This study explores the influence of infill patterns on machine acceleration prediction in the realm of three-dimensional (3D) printing, particularly focusing on extrusion technology. Our primary ...objective was to develop a long short-term memory (LSTM) network capable of assessing this impact. We conducted an extensive analysis involving 12 distinct infill patterns, collecting time-series data to examine their effects on the acceleration of the printer’s bed. The LSTM network was trained using acceleration data from the adaptive cubic infill pattern, while the Archimedean chords infill pattern provided data for evaluating the network’s prediction accuracy. This involved utilizing offline time-series acceleration data as the training and testing datasets for the LSTM model. Specifically, the LSTM model was devised to predict the acceleration of a fused deposition modeling (FDM) printer using data from the adaptive cubic infill pattern. Rigorous testing yielded a root mean square error (RMSE) of 0.007144, reflecting the model’s precision. Further refinement and testing of the LSTM model were conducted using acceleration data from the Archimedean chords infill pattern, resulting in an RMSE of 0.007328. Notably, the developed LSTM model demonstrated superior performance compared to an optimized recurrent neural network (RNN) in predicting machine acceleration data. The empirical findings highlight that the adaptive cubic infill pattern considerably influences the dimensional accuracy of parts printed using FDM technology.
Additive manufacturing (AM) is used for highly complex structures that can be stable and extremely light weight. AM also enables a design-driven manufacturing process where production is determined ...by design. Fused deposition modelling (FDM) is one of the mainly used AM technique. It is more easily accessible technique than others and also has advantages like less time consuming, usage with broad range of materials and lower costs. It is also referred to as 3D printing in which objects are produced layer by layer from a CAD model by depositing a thermoplastic filament. Mechanical properties like tensile strength and hardness plays a vital impact when various process parameters are varied on printed parts for different application. Experimental investigation on the FDM printed parts using acrylonitrile butadiene styrene (ABS) material has been carried out by varying the three process parameters namely Infill density, Infill pattern and Layer thickness. Tensile strength and hardness are utilized as response parameters. Experiments are considered by means of central composite design (CCD) of response surface methodology (RSM). The optimization has been carried out by desirability analysis. The study reveals that that infill density and layer thickness is most significant factor.
Additive manufacturing (AM) technology is an innovated production process mostly in the field of customization parts that gained the interest of many academics and industries over the last 20 years. ...The extrusion‐based technique and a wide variety of constantly developed polymer materials that AM technology uses, integrates multiple functions and mechanical properties to parts, and provides a flexibility in fabrication of complicated shapes, making products attractive to a wide range of applications. The quality and durability of those parts are controlled by numerous of building features that need to be set before building through specialized software that accompanies AM machines. A very crucial building feature that determines the inner structure of parts is lattice structure which is proved to determine the strength‐to‐weight ratio, the minimization of the material, the building time, and the energy absorption of the produced parts. However, lattice structures can be applied only to the entire geometry of a part because the software that accompanies AM machines have limited capabilities regarding the inner geometry of products since they cannot define different shell thickness values to the inner surfaces as well as multiple geometry lattice pattern to specific areas of the part. The current study proposes a new methodology of controlling the internal geometry and fatigue limits of extrusion‐based parts, bypassing the low capabilities of AM software using the meaning of design intent to insert lattice structures on specific areas of a part to produce AM products applicable to the field of fail‐safe in industry.
Distal fractures are the most commonly experienced type of fractures that require fixation of bone plates for healing of fractured bones. Poly Lactic Acid (PLA)‐based bone plates are porous and light ...in weight. However, they lack mechanical properties that limit their application in biomedical field. Polydopamine coating has been witnessed to undergo covalent interactions, enhancing the mechanical properties of the substrate. The present study is based on the fabrication of PLA‐based bone plates using Fused Filament Fabrication with varying infill patterns. The infill patterns in the study include octet, cubic, grid, concentric, lines, and gyroid. Thereafter, polydopamine coating was deposited on these bone plates using direct immersion coating method. In the study, the effect of infill pattern on coating deposition and modification of mechanical properties has been studied. The microscopic images of fractured bone plates were captured. It was concluded that polydopamine coating was successful in improving mechanical properties for all infill patterns. The findings suggested that a concentric pattern should be used for applications that require both high mechanical strength and maximum elongation at break because elongation at break is higher for concentric patterns than gyroid patterns. Also, for applications requiring only high mechanical strength, a gyroid pattern should be used.
PLA based distal ulna small locking bone plates have been fabricated using FFF with varying infill patterns. The infill patterns in the study include octet, cubic, grid, concentric, lines and gyroid. The polydopamine coating was deposited on bone plates using direct immersion method. In the study, the effect of infill pattern on coating deposition and mechanical properties have been studied.
The current investigation evaluates the compressive response of 3D-printed carbon fiber-reinforced PETG thermoplastics to optimize different infill parameters when loaded at high impact pressures ...(strain rates). The selected parameters for the 3D printing of different samples are the filling pattern (rectilinear and honeycomb) and the filling density (25%, 50%, and 75%). Compression-split Hopkinson pressure bars (SHPBs) combined with a high-speed camera were used to monitor the evolution of the mechanical behavior and damage kinetics of 3D-printed samples in real-time with the variation in strain rate. The results revealed a significant improvement in compressive strength and compressive modulus when the filling density was increased from 20% to 75% for both patterns. However, the combination of a honeycomb pattern with 75% filling presented the best compressive strength, stiffness and damage resistance, irrespective of impact pressure. In particular, the highest compressive strengths, ranging from 35.5 to 56.16 MPa for impact pressures of 1.4 to 2.4 bar, respectively, were obtained with this configuration (75% honeycomb pattern). This represents a substantial difference of 25 to 38% compared with the 75% rectilinear pattern, which showed values below 35 MPa. Another significant result was observed for the compressive modulus, which reached 2787.8 MPa for the honeycomb-filled samples, whereas this value remained below 2000 MPa for the rectilinear pattern.
The significance of 3D printing has risen exponentially in biomedical and pharmaceutical applications. Its potential in the field of fabricating drug delivery systems, by virtue of processing ...biocompatible polymers, has been very lucrative. This work aims to tap the interstitial drug delivery kinetics that are often inaccessible through machine‐specific infill patterns in additive manufactured tablets fabricated using PVA biopolymer as an excipient. In this regard, a myo‐inositol containing tablet has been printed using Fused Deposition Modeling preceded by Hot Melt Extrusion drug loading route. Two machine‐specific infill patterns were taken, namely straight and grid. Later, these two distinct patterns were juxtaposed to obtain novel hybrid infill patterns in the tablets. Then, these tablets and their filament were subjected to various thermal, mechanical, imaging and pharmaceutical characterization tests to assess the feasibility of the research attempt. Finally, dissolution tests were conducted to evaluate their dissolution behavior over a time period. The characterization tests proved the scientific viability of this attempt along with amorphous existence of drug in the polymeric filament. The dissolution results showed favorable drug release by achieving interstitial dissolution timings with surface area/volume (SA/V) ratio being found to be the principal factor.
Hybrid infill patterns and their tunable drug release characterstics.
Abstract
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.
Polylactic Acid(PLA) and Polyethylene Terephthalate Glycol(PET-G) material fabricated with Fused Filament Fabrication(FFF) method in 3D printing has been recognized as one of the important material ...in artificial tissue/bone engineering applications and adaptors of lower limb prosthesis due to its low cost and less weight. The effect of infill-pattern, infill-density, layer height and speed of the nozzle with 3D printed PLA and PET-G samples on tensile strength was carried out using Design of Experiments. PLA and PET-G samples were fabricated with Fused Filament Fabrication (FFF) method in 3D-printing process and tested using Tensile Testing Machine (UTM) for optimization of process parameters. Experiments were designed using taguchi L9 orthogonal array with five process parameters and three levels to find optimum process parameters of 3D printed samples. Confirmation experiments were conducted with optimum process parameters for both PLA and PET-G samples to compare predicted results of taguchi. The predicted results and confirmation test results reveals that both predicted taguchi results and confirmation test results were within the confident level. The taguchi analysis results evident that the layer height was the main factor affecting tensile strength of PLA samples and infill pattern was the influencing factor affecting on the tensile strength of PET-G material.
