Effects of material infill pattern and infill density on the tensile strength of products produced b

Abstract

Keywords: Additive manufacturing; infill density; infill pattern; FFF; material selection.

Introduction

All devices, systems and products that we admire for their form, usefulness and technology; it is produced as a result of successful design, correct material selection and appropriate manufacturing method. Manufacturing and design are fields that are constantly open to innovation and improvement. Traditional manufacturing methods can basically be defined under two headings: substractive methods and additive methods [1]. The main advantage of additive manufacturing compared to subtractive manufacturing is the low material loss [2]. Among these methods, additive manufacturing techniques have rapidly developed and become widespread in recent years, not only in the pro-

duction of advanced technological products, but also in the production of polymer-based products that are frequently used in daily life and can even be produced at home [3]. With 3D printers, beyond the production of prototypes, the commercial product itself is now produced. Additive manufacturing methods are seen as one of the important “mile stone”s (breaking point) in the manufacturing sector, following the Industrial Revolution [4]. Thanks to 3D printers, which are devices that work with the additive manufacturing method, in addition to rapid prototyping, it has become possible to produce complex shaped products at once, without the restriction of tool geometry. When the working logic of 3D printers is examined, it is seen that the product is manufactured by adding raw mate-

*Corresponding author. *E-mail address: pinar.koymen.cagar@ege.edu.tr Published by Yıldız Technical University Press, İstanbul, Türkiye This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

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Figure 1. Design and production processes with additive manufacturing [5]. rials one after the other in layers. For this reason, the method is also called “layer manufacturing”. Depending on the type of raw material, heating and solidification processes vary during the layer formation phase [4]. Production with the additive manufacturing method includes the following stages, as seen in Figure 1: Modeling: The design of the product to be printed is carried out with computer-aided drawing programs (CAD). Slicing: After the drawing is completed with the CAD program, the model is sliced and the layers are determined using the interface program of the three-dimensional printer. Printing and Production: Before printing, printing settings are made using the interface program. For this purpose, adjustments such as the feature of the filament to be printed, printing speed, nozzle temperature, printing chip temperature, raft settings, support material settings placed in the gaps, main product infill pattern and main product infill density are made. Secondary Post-Printing Operations: When the printed product has a form with gaps, these gaps are filled with additional parts called supports. After the product is printed, these additional - support parts must be separated from the main product. This can have a negative impact on the surface quality and smoothness of the product. Therefore, secondary processes such as sanding may be needed to ensure surface precision and increase surface quality. In 3D printers with dual nozzles, a support filament can be used in addition to the main filament. In this way, the support filament can be easily separated from the main product after printing. However, when water-soluble support filaments are used, the need to remove the support material in the cavities from the main product is eliminated. When the

Figure 2. Examples of application areas of polymers shaped by additive manufacturing [9]. product is removed from the printing tray of the 3D printer and placed in water, the support filament melts and the cavity structure is obtained without deteriorating the surface quality of the main product. Secondary operations are not limited to sanding. Glued assembly can be performed on products that are viewed in multiple parts that cannot be printed individually. This is an application that falls into the class of secondary operations. As a result of the differentiation of the material structure of the raw material used and the method of operation of the device, the production techniques of 3D printers are separated from each other [5]. Additive manufacturing methods provide designers with greater flexibility and convenience than traditional manufacturing methods, have many advantages, such as low-cost production of complex parts that do not require mass production, which will not be produced in large numbers, fewer assembly requirements, less waste generation, and the ability to update the design and dimensions in the device interface program [5, 6]. Products manufactured by additive manufacturing have lower mechanical strength than the same parts manufactured by traditional

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Figure 3. Schematic representation of various additive manufacturing methods (a) FFF, (b) SLA, (c) PolyJet, (d) SLS, (e) LOM [11]. methods. In addition, ongoing developments in 3D printing technology and filaments used as raw materials for 3D printers allow products to increase their strength and be used in a wider range of applications [6]. Additive manufacturing is widely used in various industries such as energy, automotive, aerospace, construction, machinery, molding, medical, healthcare, design and prototyping (Fig. 2) [7, 8]. The devices used in additive manufacturing have different names in the literature according to the printing techniques. These are methods such as Fused Filament Fabrication (FFF), Selective laser sintering (SLS), Stereolithography (SLA), Sheet Lamination, BinderJet, PolyJet [10]. Figure 3 shows a schematic representation of additive manufacturing methods. The most well-known method among additive manufacturing methods, which has become so widespread that it can even be used at home, is the FFF technique. Three-dimensional printers, which print with the fused deposited modelling method, are devices that are not limited to manufacturing organizations but also reaching our homes, have a wide range of preferability and widespread use, thanks to their ease of use. In these devices, product printing is carried out by melting the raw material in the form of filaments passing through the heating section called the nozzle and combining the molten filament layer by layer on the table into droplets. The nozzle, which is used to heat the raw material and turn it into a droplet, also moves on the x, y and z axes, allowing the product to be printed on the table in the desired geometry. The raw materials used in

this method are polymeric-based filaments. PLA and ABS filaments are the most commonly used raw material types. However, nowadays, as the characteristics of FFF devices have improved, the types of raw materials that they can print have also improved and diversified. The types of raw materials will be discussed in Section 2. In addition to simple, single-nozzle EYM devices with a print volume and raw material area open to the atmosphere, there are also more advanced, double-nozzle EYM devices with a closed print volume, a heated print room, a closed raw material storage area, and protecting the filament from the atmosphere and moisture. In this method, in the printing of parts with gaps, the parts suspended in the air are manufactured by supporting structures. In single-nozzle FFF devices, the support is the layers consisting of the main filament. In dual-nozzle devices, filaments with water melting properties such as high impact polystyrene (HIPS) are used for support. Thus, when the product printing is completed, it is easier to separate the supporting parts from the main part, and the surface smoothness is not disturbed. In addition to supporting material printing, FFF devices with double nozzles can print using two different color filaments on one piece or print two products at the same time. The material to be used as raw material in production with additive manufacturing method has a great influence on both the forming process and the properties of the product [12]. When we look at the most commonly used filament raw material types in the FFF method, we see filament materials such as PLA, ABS, TPU, nylon, HIPS.

Considering the effect of infill density and infil pattern on the mechanical properties of the product, it is obvious that it is necessary to compare various filaments. This comparison will help the designer to design and produce the appropriate filament, appropriate infill density, appropriate infill pattern, appropriate mechanical strength, light weight and economical product. In this context, a systematic evaluation to determine the effects of different filaments on mechanical performance is of great importance for the optimization of products manufactured with the FFF technique. In order to determine the strength of the products, standard size samples are produced and tensile tests are applied. During the tensile test, elastic-plastic deformation behavior is determined by applying axial load to the sample. The transition limit of the elastic and plastic zones reveals the yield strength of the material. Hooke's law (σ=E*ε) is valid within the elastic zone. In the elastic region, since no permanent deformation occurs, when the load applied to the material is removed, the length of the sample returns to its original state. In the plastic region, the yield stress limit is exceeded and permanent deformation occurs. Findings indicating that infill pattern and infill density play a significant role in the durability, flexibility, and overall mechanical properties of the products contribute to research in this field and provide a new perspective for applied engineering practices. Thus, considering the diversity of filaments will enable more comprehensive and effective outcomes in product design processes. In product design and manufacturing processes, material selection is of critical importance in terms of conditions of use and functionality in order to achieve optimum properties. The selection of the appropriate material alone is not enough, because various printing parameters such as infill pattern, infill density, printing temperature, nozzle diameter, table temperature, angle of placement of the product on the table affect the strength of the product manufactured from the material used. In this study, in order to provide comparison data to the literature, in addition to PLA and ABS filaments, which are widely used in additive manufacturing and FFF techniques, STH, Semiflex and PETG filaments were also used. With these 5 different filaments, tensile samples were produced with 2 different infill patterns and 2 different infill densities. Tensile test results were compared. The results obtained will benefit both designers and manufacturers in choosing appropriate materials, selecting appropriate infill pattern and printing with appropriate infill densities in order to obtain optimum product properties. The proper selection of materials and printing parameters is crucial for designers and manufacturers to produce products with optimal characteristics that exhibit structural and mechanical properties suitable for their intended use. The optimal choice of materials and printing parameters will facilitate the processes for both designers and manufacturers, eliminate uncertainties, and enable the achievement of targeted results. Raw Material Applications of FFF Printed Products Today, additive manufacturing technique is used for product printing, beyond prototype production. Preferring additive manufacturing in product printing has gained im-

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portance not only in terms of ease of production but also in terms of the features the product will have. The properties of the product such as lightness, flexibility, hardness and brittleness vary depending on the type of filament used, the infill pattern applied during printing, the infill ratio, the placement angle (orientation) on the printing plate, and the device settings such as printing speed and printing temperature. In recent years, various usage areas of products produced by additive manufacturing and the properties of products printed with the most frequently used filament types such as PLA, ABS, TPU, nylon, STH, HIPS have been investigated. PLA has a thermoplastic polymer structure. PLA, obtained from starch or glucose-based edible sources, is a bioplastic with low toxicity and high biocompatibility. It can be reinforced with other polymers to have different properties. Due to its low melting temperature, it is easy to print products by additive manufacturing method. The low cost of filament has popularized the use of PLA in the FFF method. It is defined as a sustainable and environmentally friendly material due to its recyclability [13, 14]. PLA is a preferred filament material for packaging food, producing biomedical products, producing biodegradable fabrics in the textile industry, printing various kitchen utensils with its biocompatible and biodegradable properties [15–18]. ABS; has hard and brittle structure. Printing with ABS is difficult compared to PLA filament. In addition, the high wear resistance, mechanical strength increases the use of ABS filaments in the production of many industrial products. Polyethylene Terephthalate-glycol modified (PETG); PET used in water bottles, textile fibers, food packages, is not widely used in 3D printers alone as raw material, glycol modified PETG is widely used in 3D printers. PETG is more durable and flexible than PLA. Easier to print than ABS. Due to its high moisture-wicking properties, it exhibits adhesive behavior during printing. STH is a plant-based biopolymer used in the production of various industrial products. Impact resistance, heat resistance and surface quality are high. Like STH, Semi Flex filaments are made of biopolymer and are semi-flexible. Flexible filaments are also called thermoplastic elastomers (TPE) and are soft, flexible and elastic types of filaments. Because of their high flexibility, it is difficult to extrude through FFF, in other words, to press. Thermoplastic polyurethane (TPU) is divided into several subspecies, such as TPC (thermoplastic copolyester). TPU is easier to extrude and is a widely used type of filament. TPC is resistant to chemical types and UV rays. HIPS (High impact polystyrene) is a filament, a mixture of polystyrene and rubber. Soluble in water containing limonene. It is used as backing material in dual extruder printers. It is also ideal for end product, industrial applications, prototypes and mockups due to its high strength, moderate flexibility and low shrinkage tendency. There are also several widely used types of filaments, such as nylon. Considering the literature studies, PLA filament is generally used in many studies where production is done with the FFF technique [19, 20]. Additionally, studies comparing materials such as PLA and ABS are also seen [21]. However,

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studies on infill pattern and infill density properties have been limited to a limited number of filament types in the literature. Karakoç and Uzun [22] and Yeşiloğlu [10] investigated the effects of infill pattern and infill density only on PLA filament. Alkhatib et al. [23] compared the effects of filler geometry and filler density on PLA and ABS filaments. Özmen and Ertek [5] examined the feasibility of personalized production with additive manufacturing, especially in applications such as implants and prostheses, the use of biomaterials, and the use of additive manufacturing in medical product production. They examined the types of materials used for metallic dental implants, ceramic HA/PCL and HA/PEEK orthopedic implants, polymeric stents and prostheses and contributed to the medical field. They predicted that reinforced composite materials will be used more widely in the future for printing products in the medical field with 3D printers. Gonçalves et al. [24], who conducted research on dental protectors, stated that sports mouth guards can be produced faster and more simply with additive manufacturing, which provides advantages for both dentistry and the sports world, instead of traditional production methods. Park et al. [25] conducted a study on the development of fall protection trousers for older women. They have designed a pad with a mesh structure for the hip area of the protective trousers to protect the body by reducing the impact of impact. They printed the protective pad they designed with the FFF technique, using thermoplastic polyurethane (TPU) filament, which is a flexible filament material. Printing flexible and soft TPU filament requires a 3D printer with a dual-gear, direct drive extruder. It was stated that the impact-protected pad developed in the study and produced by the additive manufacturing method was suitable for the body shapes of elderly women and provided ease of daily use. Similarly, Yahaya et al. [26] produced a pad that protects the body from impacts caused by falling using a resin-derived VeroWhite raw material with an SLA type 3D printer. In his study in 2020, Habib examined the energy absorption of thermoplastic honeycomb structures printed using Nylon12 filament with an FFF type 3D printer. It has been demonstrated that honeycomb structures with high energy absorption can be effectively produced with a 3D printer [27]. Narlıoğlu [28] obtained wood-PLA composite filament by adding wood flour to PLA filament. Test samples were printed on FFF type printers using various printing speeds with wood-PLA filament and compared the shrinkage and hardness values depending on the printing speed. They observed that as the printing speed increased, the tensile strength first increased and then decreased. They stated that the mechanical properties of the materials are at optimum values at medium printing speeds. Özsoy et al. [21] produced tensile and bending samples with PLA and ABS filaments on a 3D printer using the FFF technique and compared the effects of PLA and ABS on the mechanical properties of the product. In their studies, they showed that increasing the infill density increased the mechanical properties of the product and that the mechanical strength of PLA was higher than ABS. In this study, only the

occupancy rates of products produced from PLA and ABS filaments were examined. The infill density of other types of filaments and the effects of changing the infill pattern applied during printing have not been examined. Demir examined the effect of 3D printer parameters on the surface hardness of samples produced with PLA filament. By changing the printer parameters nozzle diameter, nozzle temperature, layer height and mesh angle, samples were produced in 9 different combinations. This study was carried out to determine the most suitable printing parameters for the hardness values of PLA samples to be produced using the fused filament fabrication (FFF) method. According to the results of the hardness tests, it was determined that the most influential variable was the nozzle diameter. It was observed that as the nozzle diameter increased, the surface hardness values of PLA samples also increased. It was found that the effect of mesh angle and nozzle temperature on hardness was low. The highest hardness; it was revealed that it was achieved with the parameters of 210°C nozzle temperature, 0.6mm nozzle diameter, 0.1mm layer thickness and 30° mesh angle [6]. As in Demir's work, Karakoç and Uzun [22] also worked with PLA filaments. Karakoç and Uzun [22] printed tensile samples with the FFF using PLA filament and examined the effects of the infill pattern and the printing direction on the mechanical properties of the samples. In the study, the infill rate was kept constant at 20% and three different infill patterns were applied and straight lines, rotating lines and honeycomb. However, during sample printing, placement angles on the table were chosen in two different ways: horizontal and vertical. In conclusion; they observed that the load resistance of the samples printed by placing them vertically on the table was higher than the samples placed horizontally. Among the horizontally placed samples, it was revealed that the yield strength of the samples printed with straight-line filler geometry was high. However, they determined that the tensile and rupture strengths of the samples printed with the rotational line infill geometry were high. They showed that horizontal samples with straight lines and honeycomb infill pattern had higher elongation rates compared to vertical ones. They found that the filament weight used did not have a direct effect on the mechanical properties of the sample [22]. Aydin et al. [20] printed tensile samples with different writing parameters using PLA filament. Thus, they examined the effects of writing parameters on products produced with PLA filament. According to their findings, they argue that printing processes are more effective at temperatures above 200°C due to low viscosity, the highest hardness value occurs at 220°C at a speed of 70 mm/s, and increasing the printing speed at the same temperature reduces the tensile stress and strength of the material. Kaygusuz and Özerinç [19] examined the changes in mechanical properties by changing the nozzle temperature and infill density, again using PLA filament. They varied the nozzle temperature between 190–215 °C and the fill density between 10% and 100%. According to their results; they observed that the change in both parameters caused a significant change in the mechanical properties of the sam-

ple printed from PLA. It has been stated that as the nozzle temperature increases, the structural voids decrease and the tensile strength increases. It was determined that the yield strength and elasticity modulus decreased by decreasing the infill density. They found that the strength of samples with 20% infill density decreased by half compared to samples with 100% density. However, they stated that low infill density may be preferred in cases where the weight is low and production speed is required to be high, and high infill density may be preferred in cases where ductility and impact resistance are important [19]. Kaya et al. [29] produced samples with 25%, 50%, 75% and 100% infill ratios and triangular - hexagonal infill patterns using PLA filament with the FFF technique. Then, the effects of infill ratio and infill pattern on the mechanical properties of the samples were interpreted by tensile, compression and three-point bending tests. At 25% infill rate, samples produced with triangular infill geometry provided higher specific strength under tensile load than other samples. While samples produced with triangular infill geometry at 50% infill rate showed optimum strength under compressive stress, samples produced with hexagonal infill geometry at 75% infill rate showed optimum strength under three-point bending load. They stated that in both infill patterns, samples produced at 75% infill rate showed better performance than 100% filled samples. As seen in the study by Kaya et al. [29], PLA filaments were evaluated on their own, and the data obtained were not compared with various filaments. Yeşiloğlu [10] produced samples with 3 different infill patterns and 3 different densities using PLA filament, and examined the mechanical properties of the samples with impact, tensile and compression tests. As a result of the study, it was revealed that the compressive strength of PLA samples decreased as the infill density decreased, the impact strength of the samples with Octet infill pattern was low, the tensile strength was high, and the yield strength in horizontal compression was low. Taşdelen et al. [30] recycled the residues of PLA and ABS filaments and turned them into filaments again by extrusion method. Thus, their reuse is ensured, contributing to both ecological and economic sustainability. In the study, the products obtained with recycled filament were compared with the products produced with original filament, and the performance of the recycled filament in the 3D printer was evaluated. It has been stated that 3D printed filaments cannot be produced from some thermoplastic materials due to the shrinkage effect that occurs during solidification from the melt, and the strength of products produced from recycled filaments is lower than the products obtained from original filaments. Özsoy and Kayacan [31] carried out prototyping of a lightweight personalized skull implant using PLA filament using the melt deposition method. According to their results; designing it in personalized shapes and sizes increases the usability of the product. The fact that it is lightweight not only saves material but also increases its preferability due to its low weight. It is expected to be high.

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Figure 4. ASTM D638 Type I Tensile Specimen Dimensions [10]. Eryıldız [32] examined the effect of orientation on mechanical strength in products produced using PLA filament with the FFF technique. The effect of orientation was evaluated by printing tensile samples with 5 different placement angles on the table of the 3D printer. According to their results, tensile strength decreased when the printing angle was from 0° to 90°. Samples printed at right angles showed 36% less tensile strength compared to straight ones. He stated that the printing angles of the parts are effective on the tensile strength and printing time. It can be seen from the literature review that many researches have been carried out on additive manufacturing methods in recent years. Considering the literature studies on filament material comparisons, it has been determined that different infill patterns and different infill densities have been studied and most of these studies have been carried out with PLA filaments. The infill pattern and infill density properties of filaments with different contents have not been examined together and no comprehensive comparison has been made between filament materials. This research article was designed to close the gap in the literature in this field and to provide data to the literature. In this study, samples were produced using filaments with 5 different material contents, 2 different infill patterns and 2 different infill densities, and the mechanical properties of the samples were compared with the tensile test results.

Materials And Methods

In this study; the effects of filament properties, infill density and infill patterns on the mechanical properties of the product were observed. In this context, sample design was carried out according to ASTM D638 to determine the tensile behavior of the samples. ASTM-D638 standard; it includes Type I, Type II, Type III, Type IV and Type V samples that can be used for composites, plastics and rigid pipes. In this article, the Type I tensile sample in Figure 4 was used to determine the mechanical properties of the samples. ASTM D638 Type I tensile samples were printed with a Zortrax M200 three-dimensional printer (Fig. 5), which works with the FFF method, has one extruder and has a 0.4 mm diameter nozzle. First, the tensile sample was drawn in the SolidWorks computer-aided design program and saved in .stl format. Then, the .stl file was opened in the Z-Suite interface program and various settings were made such as placement settings on the table of the Zortrax M200 3D printer, assignment of filament material, determination of table temperature and nozzle temperature depending on the material type, selection of infill pattern and infill densi-

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ty, use of raft material on the table. The slicing process of the drawn product was defined in the interface program and a file with the .zcode extension was created. The .zcode file was run on the 3D printer and the product printing was started according to the determined settings. As materials; five types of filaments with a diameter of

Results And Discussion

Within the scope of the study, the effects of infill ratios and infill patterns on the tensile strength of products printed with the FFF technique according to the type of filament material were examined. For this purpose, ASTM D638 Type 1 tensile sample was printed on a 3D printer using the FFF technique, using 5 different filament materials. Figure 7 shows photographs of the printing of samples with 30% and 60% infill densities in honeycomb infill pattern on Zortrax M200 branded FFF type 3D printer. Figure 8 shows photographs of the printing of samples with 30% and 60% infill densities in linear infill pattern. 4 different types of tensile samples were produced from 5 different filament types and a total of 60 samples were produced to perform 3 repeated tensile tests. Figure 9 shows labeled photographs of some of the samples after printing and before the tensile test. Table 1 contains raw data from the Shimadzu Ag-Is tensile device before calculating engineering stresses for each test specimen. The data in question was later processed in the Microsoft Office Excel program. The "engineering tensile stress" was calculated by dividing the maximum force applied during the tensile test by the sample cross-sectional area. The "unit elongation" was calculated by dividing the values obtained from the extensometer by the initial length of the sample. Then, the following curves were drawn in the Microsoft Office Excel program. Then, the tensile curves were drawn in the Microsoft Office Excel program. Samples with linear infill pattern have a closer, more regular internal structure. Honeycomb structure samples have a hollow geometric structure. Sample weights were measured by precision scales. In addition, sample weights are

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Figure 7. Printing of specimens with honeycomb infill pattern with (a) 30 % (b) 60 % infill density.

Figure 8. Printing of specimens with linear infill pattern with (a) 30 % (b) 60 % infill densit. given on the report page obtained when the printing settings are completed in the Z-Suite interface program. In Table 2, as the infill density increases, an increase of 0.085 grams in PETG, 0.1 grams in STH and Semiflex, 0.2 grams in ABS and 0.5 grams in PLA material was detected in the weight of the honeycomb infill pattern samples. Therefore, it was interpreted that there was no significant change in the weight of the samples with honeycomb infill pattern depending on the infill density. However, in samples with linear pattern, when the infill density increased from 30% to 60%, a weight increase of 0.513 grams was recorded in PETG, 0.588 grams in Semiflex, 0.703 grams in ABS, 1.004 grams in PLA and

Conclusion

The production of polymeric materials via additive manufacturing is a rapidly expanding topic that has the potential to impact many industries. Due to its customizable, personalizable, sustainable and flexible design and rapid production of complex designs, additive manufacturing has the potential to revolutionize many industries and be an important driving force for innovative approaches. In numerous manufacturing studies conducted using the FFF method, commonly used materials such as PLA and ABS are typically preferred. However, existing research in the literature has primarily investigated the properties of infill geometry and infill density with a limited variety of filaments. Given the impact of infill density and infill geometry on the mechanical properties of produced products, the necessity for a comparative analysis of various filaments becomes clearly evident. In this study, tensile samples with two different filler densities and two different filler geometries were printed using the FFF technique using PLA, ABS, STH, Semiflex and PETG filaments. By evaluating the data obtained as a result of the tensile test, the following results were reached.

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The change of both infill density and infill pattern caused different behaviors in terms of maximum tensile strength depending on the filament material content. Among ABS and PLA materials, which are the most commonly used filament materials in 3D printers today, the sample with a linear infill pattern and a 60% infill density exhibited the highest tensile strength. Similar to PLA and ABS, the samples with linear infill pattern and 60% infill density exhibited the highest tensile strength in STH and Semiflex materials. The sample with honeycomb infill pattern and 30% infill density exhibited the highest tensile strength in PETG material. Considering the tensile test results given in Table 1, it is possible to determine the linear infill pattern as the optimum pattern because it shows close or higher tensile strength than samples with honeycomb infill pattern. When the samples with linear infill pattern were compared, when the infill density increased from 30% to 60%, the maximum tensile strength increased by 4.6% in Semiflex material, 5.66% in PLA material, 9% in ABS material and 11% in STH material. Material type, infill ratio and infill pattern cause changes in the mechanical properties and lightness of the product. It was observed that there was no significant change in the weight of the samples with honeycomb pattern depending on the infill density. However, in the samples with linear pattern structure, an increase in weight was recorded when the infill density increased from 30% to 60%. Correct selection of materials and printing parameters is important for the designer and manufacturer to print products with optimum properties and for the product to exhibit structural and mechanical properties suitable for its intended use. Optimum selection of materials and printing parameters will provide convenience for both the designer and the manufacturer, eliminate uncertainties and ensure target-oriented results. For this reason, in future studies, parameters such as various infill densities, infill pattern, orientation resulting from the placement angle on the table, printing speed, printing temperature, nozzle diameter on various filament materials should be continued to be studied and continue to provide data to the literature.

Data Availability Statement

The authors confirm that the data that supports the findings of this study are available within the article. Raw data that support the finding of this study are available from the corresponding author, upon reasonable request.

Conflict of Interest

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Use of AI for Writing Assistance Not declared.

Ethics

There are no ethical issues with the publication of this manuscript.

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