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Most support surfaces in comfort applications and sporting equipment are made from pressure-relieving foam such as viscoelastic polyurethane. However, for some users, foam is not the best material as it acts as a thermal insulator and it may not offer adequate postural support. The additive manufacturing of such surfaces and equipment may alleviate these issues, but material and design investigation is needed to optimize the printing parameters for use in pressure relief applications. This study aims to assess the ability of an additive manufactured flexible polymer to perform similarly to a viscoelastic foam for use in comfort applications.

Three-dimensional (3D) printed samples of thermoplastic polyurethane (TPU) are tested in uniaxial compression with four different infill patterns and varying infill percentage. The behaviours of the samples are compared to a viscoelastic polyurethane foam used in various comfort applications.

Results indicate that TPU experiences an increase in strength with an increasing infill percentage. Findings from the study suggest that infill pattern impacts the compressive response of 3D printed material, with two-dimensional patterns inducing an elasto-plastic buckling of the cell walls in TPU depending on infill percentage. Such buckling may not be a beneficial property for comfort applications. Based on the results, the authors suggest printing from TPU with a low-density 3D infill, such as 5% gyroid.

Several common infill patterns are characterised in compression in this work, suggesting the importance of infill choices when 3D printing end-use products and design for manufacturing.

This study aims to identify the effects of infill patterns and infill percentages on the energy consumption (EC) of fused filament fabrication (FFF). With increasing attention on carbon-fiber-reinforced–poly-ether-ether-ketone (CFR-PEEK) for practical applications in FFF, infill pattern and infill percentage for FFF can be properly controlled to achieve better energy performance of CFR-PEEK outputs. However, the effects of infill parameters on EC for FFF using CFR-PEEK have not been clearly addressed yet.

Using a full factorial experimental design, six types of infill patterns (rectilinear, grid, triangular, wiggle, fast honeycomb and full honeycomb) and four different infill percentages (25%, 50%, 75% and 100%) were considered for a design of experiments with three replicates. Then, analysis of variance, Tukey test and regression analysis were performed to investigate both the effects of infill pattern and infill percentage on energy performance during FFF.

EC is characterized to be high for the wiggle and triangular patterns and low for the rectilinear pattern during both the printing stage and the entire process. The wiggle pattern results in the greatest increase in EC, whereas the rectilinear pattern leads to the least increase in EC. Although EC during the FFF process increases as the infill percentage increases, the average power demand during the printing stage decreases.

Both the main and interaction effects of infill pattern and infill percentage are investigated to estimate EC and power during the different process stages of FFF.

As newer high performance polymers in mechanical properties become available for material extrusion-based additive manufacturing, determining infill parameter settings becomes more important to achieve both operational and mechanical performance of printed outputs. For the material extrusion of carbon fiber reinforced poly-ether-ether-ketone (CFR-PEEK), this study aims not only to identify the effects of infill parameters on both operational and mechanical performance but also to derive appropriate infill settings through a multicriteria decision-making process considering the conflicting effects.

A full-factorial experimental design to investigate the effects of two major infill parameters (i.e. infill pattern and density) on each performance measure (i.e. printing time, sample mass, energy consumption and maximum tensile load) is separately performed to derive the best infill settings for each measure. Focusing on energy consumption for operational performance and maximum tensile load for mechanical performance, the technique for order preference by similarity to ideal solution is further used to identify the most appropriate infill settings given relative preferences on the conflicting performance measures.

The results show that the honeycomb pattern type with 25% density is consistently identified as the best for the operational performance measures, while the triangular pattern with 100% density is the best for the mechanical performance measure. Moreover, it is suggested that certain ranges of preference weights on operational and mechanical performance can guide the best parameter settings for the overall material extrusion performance of CFR-PEEK.

The findings from this study can help practitioners selectively decide on infill parameters by considering both operational and mechanical aspects and their possible trade-offs.

Fibre-reinforced additive manufacturing (FRAM) with short and continuous fibres yields light and stiff parts and thus increasing industry acceptance. High material anisotropy and specific manufacturing constraints shift the focus towards design for AM (DfAM), particularly on toolpath strategies. Assessing the design-property-processing relations of infill patterns is fundamental to establishing design guidelines for FRAM.

Subject to the DfAM factors performance, economy and manufacturability, the efficacy of two conventional infill patterns (grid and concentric) was compared with two custom strategies derived from the medial axis transformation (MAT) and guided by the principal stresses (MPS). The recorded stiffness and strength, the required CPU and print time, and the degree of path undulation and effective fibre utilisation (minimum printable fibre length) associated with each pattern, served as assessment indices for different case studies. Moreover, the influence of material anisotropy was examined, and a stiffness-alignment index was introduced to predict a pattern’s performance.

The highest stiffnesses and strengths were recorded for the MPS infill, emphasising the need for tailoring print paths rather than using fixed patterns. In contrast to the grid infill, the concentric infill offered short print times and reasonable utilisation of continuous fibres. The MAT-based infill yielded an excellent compromise between the three DfAM factors and experimentally resulted in the best performance.

This constitutes the first comprehensive investigation into infill patterns under DfAM consideration for FRAM, facilitating design and processing choices.

This paper aims to investigate the effects of build parameters and strain rate on the mechanical properties of three-dimensional (3D) printed polylactic acid (PLA) by integrating digital image correlation and desirability function analysis. The build parameters included in this paper are the infill density, build orientation and layer height. These findings provide a framework for systematic mechanical characterization of 3D-printed PLA and potential ways of choosing process parameters to maximize performance for a given design.

The Taguchi method was used to shortlist a set of 18 different combinations of build parameters and testing conditions. Accordingly, 18 specimens were 3D printed using those combinations and put through a series of uniaxial tensions tests with digital image correlation. The mechanical properties deduced for all 18 tests were then used in a desirability function analysis where the mechanical properties were optimized to determine the ideal combination of build parameters and strain rate loading conditions.

By comparing the tensile mechanical experimental properties results between Taguchi's recommended parameters and the optimal parameter found from the response table of means, the composite desirability had increased by 2.08%. The tensile mechanical properties of the PLA specimens gradually decrease with an increase in the layer height, while they increase with increasing the infill densities. On the other hand, the mechanical properties have been affected by the build orientation and the strain rate in similar increasing/decreasing trends. Additionally, the obtained optimized results suggest that changing the infill density has a notable impact on the overall result, with a contribution of 48.61%. DIC patterns on the upright samples revealed bimodal strain patterns rendering them more susceptible to failures because of printing imperfections.

These findings provide a framework for systematic mechanical characterization of 3D-printed PLA and potential ways of choosing process parameters to maximize performance for a given design.

This paper aims to explore the effect of bed temperature, primary layer thickness and infill pattern (rectilinear, honeycomb, triangular) on the mechanical properties of tensile strength and bending strength of 3D printed parts.

Samples in accordance to various ASTM standards were printed by fused deposition modelling (FDM) method by varying the various input paramaters such as bed temperature, primary layer thickness and infill pattern (rectilinear, honeycomb, triangular). Tensile and bending testing was carried out on the printed parts, and post to the testing, fractography has been carried out using scanning electron microscope.

With increase in bed temperature tensile strength and flexural strength first increases then decreases. With the increase in primary layer thickness, tensile strength and flexural strength increase. With regard to infill patterns, triangular and honeycomb exhibit better tensile strength and better flexural strength.

The 3D printing is increasingly becoming important for manufacturing of engineering parts, determining the process parameters which could result in better mechanical and physical properties shall certainly help designers and manufacturers globally.

This work elucidates the effect of various process parameters of FDM on tensile and flexural properties of the samples.

The purpose of this study is to investigate how the amount of material used and printing parameters affect the mechanical and water sorption properties of acrylonitrile butadiene styrene printed parts.

The specimens were printed using different printing parameters such as shell number, infill pattern and printing orientation, while accounting for the amount of material used. The mechanical properties of the printed parts were then evaluated using tensile, compression and flexural tests, along with sorption tests.

The results revealed that the maximum tensile stress of 31.41 MPa was obtained when using 100% infill and a horizontal printing orientation. Similarly, the maximum flexural strength and compression of 40.5 MPa and 100.7 MPa, respectively, were obtained with 100% infill. The printing orientation was found to have a greater impact on mechanical behavior compared to the number of shells or infill patterns. Specifically, the horizontal printing orientation resulted in specimens with at least 25% greater strength compared to the vertical printing orientation. Furthermore, the relationship between the amount of material used and strength was evident in the tensile and flexural tests, which showed a close correlation between the two.

This study’s originality lies in its focus on optimizing the amount of material used to achieve the best strength-to-mass ratio and negligible water infiltration. The findings showed that specimens with two shells and a 60% infill density exhibited the best strength-to-mass ratio.

The mechanical performances of 3D-printed parts are influenced by the manufacturing variables. Many studies experimentally evaluate the impact of the process parameters on specimens’ static and dynamic behavior with the aim of tailoring the mechanical response of the prints. However, this experimental approach is hampered by the very large number of parameters, 3D printers and materials, the development of computer simulation models being thus required. In the context, this study aims to fill a gap by experimentally investigating the influence of infill related parameters over the vibrations of 3D-printed specimens, as well as to propose and validate a parametric finite element (FE) model for the prediction of eigenfrequencies.

A generally applicable FE model is not yet available for the 3D printing technology based on the material extrusion process due to the large number of parameters settings that determine a large variability of outcomes. Hence, the idea of developing numerical simulation models that address sets of parameters and assess their impact on a certain mechanical property. For the natural frequency, the influence of the infill density and infill line width is studied in this paper. An FE script that automates the generation of the model geometry by using the considered set of parameters is developed and run. The results of the modal analysis are compared to the experimental values for validating the script.

Based on the experimental results, a linear regression between the weight of the part and the first natural frequency is established. The response surfaces indicate that the infill density is the most significant parameter of influence. The weight-frequency function is then used for the prediction of the natural frequency of specimens manufactured with other infill parameters and values, including different infill patterns.

As the malfunctions or mechanical damages can be caused by the resonant vibration of parts during use, this research develops a FE-parameterized model that evaluates and predicts the eigenfrequencies of 2D printed parts to prevent these undesirable events. The targeted functional applications are those in which 3D-printed polymer parts are used, such as drone arms or drone propellers.

This research studies the influence of process parameters on the natural frequency of 3D-printed polylactic acid specimens, a topic scarcely addressed in literature. It also proposes a new approach for the development of parameterized FE models for sets of parameters, instead of a general model, to reduce the time and resources allocated to the experimental tests. Such a model is provided in this paper for evaluating the influence of infill parameters on 3D prints eigenfrequency. The numerical model is validated for other infill settings.

The purpose of this study, most recent advancements in threedimensional (3D) printing have focused on the fabrication of components. It is typical to use different print settings, such as raster angle, infill and orientation to improve the 3D component qualities while fabricating the sample using a 3D printer. However, the influence of these factors on the characteristics of the 3D parts has not been well explored. Owing to the effect of the different print parameters in fused deposition modeling (FDM) technology, it is necessary to evaluate the strength of the parts manufactured using 3D printing technology.

In this study, the effect of three print parameters − raster angle, build orientation and infill − on the tensile characteristics of 3D-printed components made of three distinct materials − acrylonitrile styrene acrylate (ASA), polycarbonate ABS (PC-ABS) and ULTEM-9085 − was investigated. A variety of test items were created using a commercially accessible 3D printer in various configurations, including raster angle (0°, 45°), (0°, 90°), (45°, −45°), (45°, 90°), infill density (solid, sparse, sparse double dense) and orientation (flat, on-edge).

The outcome shows that variations in tensile strength and force are brought on by the effects of various printing conditions. In all possible combinations of the print settings, ULTEM 9085 material has a higher tensile strength than ASA and PC-ABS materials. ULTEM 9085 material’s on-edge orientation, sparse infill, and raster angle of (0°, −45°) resulted in the greatest overall tensile strength of 73.72 MPa. The highest load-bearing strength of ULTEM material was attained with the same procedure, measuring at 2,932 N. The tensile strength of the materials is higher in the on-edge orientation than in the flat orientation. The tensile strength of all three materials is highest for solid infill with a flat orientation and a raster angle of (45°, −45°). All three materials show higher tensile strength with a raster angle of (45°, −45°) compared to other angles. The sparse double-dense material promotes stronger tensile properties than sparse infill. Thus, the strength of additive components is influenced by the combination of selected print parameters. As a result, these factors interact with one another to produce a high-quality product.

The outcomes of this study can serve as a reference point for researchers, manufacturers and users of 3D-printed polymer material (PC-ABS, ASA, ULTEM 9085) components seeking to optimize FDM printing parameters for tensile strength and/or identify materials suitable for intended tensile characteristics.

This paper aims to evaluate the mechanical behaviour of polycarbonate/acrylonitrile butadiene styrene (PC/ABS) filaments for fusion filament fabrication (FFF). PC/ABS have emerged as a promising material for FFF due to their excellent mechanical properties. However, the optimal processing conditions and the effect of the blending ratio on the mechanical properties of the resulting workpieces are still unclear.

A statistical factorial matrix was designed, including infill pattern, printing speed, nozzle size, layer height and printing temperature as factors (with three levels). A total of 810 workpieces were printed using PC/ABS blends filament with the FFF. The workpieces’ finishing and mass were evaluated. Tensile tests were performed. Analysis of variance was performed to determine the main effects of the processing conditions on the mechanical properties.

The results showed that the PC/ABS (70/30) exhibited higher tensile. Tensile rupture corresponded to 30% of the tensile strength. The infill pattern showed the highest contribution to the responses. The concentric pattern showed higher tensile strength. Tensile strength and mass ratio demonstrated the influence of mass on tensile strength. The influence of printing parameters on deformation depended on the blend proportions. Higher printing speed and lower layer height provided better quality workpieces.

This study has implications for the design and manufacturing of three-dimensional printed parts using PC/ABS filaments. An extensive experimental matrix was applied, aiming at a complete understanding of mechanical behavior, considering the main printing parameters and combinations not explored by literature.