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As a typical 3D printing process, fused filament fabrication still has disadvantages when operating on manufacturing lines due to the non-uniform textures of the oriented surfaces of the 3D-printed components. This work investigates the effects of structural parameters, i.e., orientations angle, ABS and PLA materials, three different layer thicknesses, three different perimeters, and three different infill rates utilizing a balanced modified Taguchi experimental design and 63 different parametric combinations to characterize the surface roughness parameters: average Ra, mean roughness depth Rz, root mean square Rq, skewness Rsk, and kurtosis Rku. The analysis of the experimental results, i.e., the levels mean values analysis plots and linear residual analysis of variances, showed that the layer thickness strongly influences all surface parameters and interacts considerably with all orientations. In contrast, material type, number of perimeters, and infill rate had insignificant impacts on surface roughness parameters. Finally, the additive linear modelling approach was utilized and validated for proper predictions, making it helpful for surface engineering applications. [ABSTRACT FROM AUTHOR]

Disposing of non-biodegradable conventional polymers such as polyethylene, polypropylene, polyvinyl chloride, and acrylonitrile-butadiene-styrene (ABS) is a severe environmental problem across the globe. ABS, a non-biodegradable polymer, is widely used for producing auto components, home appliances, electronic goods, etc., but it is not environment friendly. Therefore, there is a pressing need to develop biodegradable polymers as an alternative to non-biodegradable polymer materials. This paper aims to offer blended bio-based polylactic-acid (PLA) polymer with ABS for engineering applications to minimize the consumption of virgin petroleum-based ABS polymer. The effort is to ascertain the best-suited composition of ABS/PLA blended polymer with excellent thermal and mechanical properties. The five specimens of blended ABS/PLA polymers have been prepared using four compositions (80/20, 60/40, 40/60, and 20/80) using the material extrusion (MEX) 3D printing process and assessed for mechanical and thermal properties. The tensile strength and MFR of the ABS/PLA blend increased by 8.75 and 124.35%, respectively, with ABS/PLA polymers having a 20/80 wt.% composition. The thermal analysis of blends with varying blend compositions using DSC and FTIR have shown partial compatibility between ABS and PLA polymers. Furthermore, scanning electron microscopy (SEM) of tensile fractured specimens has been analyzed to support the evidence. [ABSTRACT FROM AUTHOR]

The paper describes the type of changes in the structure and mechanical properties of 3D printed shapes under the influence of mineral oil. The effects of a room (23 °C) and elevated temperature (70 °C) on 3D prints manufactured by the FDM method and stored in oil for 15, 30, and 60 days on the change of properties and structure were investigated. The samples were produced from ABS (poly(acrylonitrile-co-butadiene-co-styrene)), ASA (poly(acrylonitrile-co-styrene-co-acrylate), PLA (poly(lactic acid)), and HIPS (high-impact polystyrene). Tests related to the strength of the materials, such as the static tensile test and Charpy impact test, were carried out. The structure was evaluated using a scanning electron microscope, and changes in chemical structure were determined by conducting FTIR (Fourier transform infrared spectroscopy) and TGA (thermogravimetric analysis) tests. The analysis of the results provided important information about the impact of mineral oil on specific materials. This is critical for designing and manufacturing components that can withstand mineral oil exposure in real-world environments. The materials underwent varying changes. Strength increased for PLA by about 28%, remained unchanged for ABS and HIPS during exposure for 30 days, and decreased for ASA with extended exposure up to 14%. [ABSTRACT FROM AUTHOR]

This study investigated the influence of two key printing parameters--namely, layer thickness and infill percentage and also the annealing effect, on the hardness of PLA and ABS components. Employing the design of experiment (DOE) methodology, the most significant factor influencing the Shore D hardness values for each material was established, in addition to determining the optimal printing parameters that yield maximum hardness in the printed parts. Our findings reveal that layer thickness significantly impacts the hardness of 3D printed PLA and ABS specimens, with printing infill percentage exerting a comparatively smaller influence, while in case of PLA annealed samples, the most significant factor is infill percentage. [ABSTRACT FROM AUTHOR]

Copyright of Investigación e Innovación en Ingenierías is the property of Universidad Simon Bolivar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Three-dimensional (3D) printer usage in household and school settings has raised health concerns regarding chemical and particle emission exposures during operation. Although the composition of 3D printer emissions varies depending on printer settings and materials, little is known about the impact that emissions from different filament types may have on respiratory health and underlying cellular mechanisms. In this study, we used an in vitro exposure chamber system to deliver emissions from two popular 3D-printing filament types, acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA), directly to human small airway epithelial cells (SAEC) cultured in an air–liquid interface during 3D printer operation. Using a scanning mobility particle sizer (SMPS) and an optical particle sizer (OPS), we monitored 3D printer particulate matter (PM) emissions in terms of their particle size distribution, concentrations, and calculated deposited doses. Elemental composition of ABS and PLA emissions was assessed using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX). Finally, we compared the effects of emission exposure on cell viability, inflammation, and metabolism in SAEC. Our results reveal that, although ABS filaments emitted a higher total concentration of particles and PLA filaments emitted a higher concentration of smaller particles, SAEC were exposed to similar deposited doses of particles for each filament type. Conversely, ABS and PLA emissions had distinct elemental compositions, which were likely responsible for differential effects on SAEC viability, oxidative stress, release of inflammatory mediators, and changes in cellular metabolism. Specifically, while ABS- and PLA-emitted particles both reduced cellular viability and total glutathione levels in SAEC, ABS emissions had a significantly greater effect on glutathione relative to PLA emissions. Additionally, pro-inflammatory cytokines including IL-1β, MMP-9, and RANTES were significantly increased due to ABS emissions exposure. While IL-6 and IL-8 were stimulated in both exposure scenarios, VEGF was exclusively increased due to PLA emissions exposures. Notably, ABS emissions induced metabolic perturbation on amino acids and energy metabolism, as well as redox-regulated pathways including arginine, methionine, cysteine, and vitamin B3 metabolism, whereas PLA emissions exposures caused fatty acid and carnitine dysregulation. Taken together, these results advance our mechanistic understanding of 3D-printer-emissions-induced respiratory toxicity and highlight the role that filament emission properties may play in mediating different respiratory outcomes. [ABSTRACT FROM AUTHOR]

Polylactic Acid (PLA) and Acrylonitrile–Butadiene–Styrene (ABS) are commonly used polymers in 3D printing for biomedical applications. Dental Pulp Stem Cells (DPSCs) are an accessible and proliferative source of stem cells with significant differentiation potential. Limited knowledge exists regarding the biocompatibility and genetic safety of ABS and PLA when in contact with DPSCs. This study aimed to investigate the impact of PLA and ABS on the adhesion, proliferation, osteogenic differentiation, genetic stability, proteomics, and immunophenotypic profile of DPSCs. A total of three groups, 1- DPSC-control, 2- DPSC+ABS, and 3- DPSC+PLA, were used in in vitro experiments to evaluate cell morphology, proliferation, differentiation capabilities, genetic stability, proteomics (secretome), and immunophenotypic profiles regarding the interaction between DPSCs and polymers. Both ABS and PLA supported the adhesion and proliferation of DPSCs without exhibiting significant cytotoxic effects and maintaining the capacity for osteogenic differentiation. Genetic stability, proteomics, and immunophenotypic profiles were unaltered in DPSCs post-contact with these polymers, highlighting their biosafety. Our findings suggest that ABS and PLA are biocompatible with DPSCs and demonstrate potential in dental or orthopedic applications; the choice of the polymer will depend on the properties required in treatment. These promising results stimulate further studies to explore the potential therapeutic applications in vivo using prototyped polymers in personalized medicine. [ABSTRACT FROM AUTHOR]

Additive manufacturing is rapidly growing in popularity for manufacturing parts with tunable mechanical properties. Recent studies show that mechanical properties can be achieved by controlling the layer orientation and build structure. In this work the effect of print orientation on tribological properties of 3D printed PLA and ABS are investigated. PLA and ABS samples are printed using fused deposition modeling (FDM) with three different print orientations. Tribological results show that variation in build direction relative to the sliding direction causes anisotropy in wear properties. The best wear properties are achieved with the samples printed where the layers remain orthogonal to the sliding direction. The coefficient of friction remains mostly unaffected by print orientation. PLA samples demonstrate significantly better tribological properties compared to ABS. Varying the sliding speed between the interacting surfaces also affects the wear properties of both PLA and ABS. The results suggest that optimizing the build orientation can improve the wear performance of additively manufactured thermoplastics. This enables an additional paradigm when designing for functionally graded materials.

3D printers have been the focus of many researchers in recent years. Many thin-walled structures can be produced using 3D printers. One of the thin wall structures that can be made with 3D printers is the core of sandwich panels. In this research, cores with rectangular cross section have been made using Acrylonitrile Butadiene Styrene (ABS) and Polylactic Acid (PLA) filaments. These cores were reinforced using aluminum and composite face sheets and subjected to a three-point bending test. Glass fibers with a density of 200 g/m2 were used to make composite shells. The results showed that the addition of aluminum and composite face sheets, although increasing the flexural strength, greatly reduces the flexibility of the core.

Thermoplastic additive manufacturing (AM) is an attractive process for fabricating cryogenic componentry, due to the potential for rapid, on-site parts replacement. However, using a process intended for low-feature prototypes in such a demanding application creates survivability concerns. AM further introduces significant material variability that complicates materials qualification. Herein, a highly-repeatable test procedure is developed to qualify as-manufactured samples. Fused Filament Fabrication (FFF) is used to produce both test samples and custom immersion equipment for cryogenic tensile testing, and data quality is improved by modifying the ASTM Type IV geometry. Tensile strength is measured directly, while elastic modulus is calculated using temperature measurements and thermomechanical model fitting. Via this methodology, cryogenic performance is characterized for Polylactic Acid (PLA), Acrylonitrile Butadiene Styrene (ABS), and Glycol-Modified Polyethylene Terephthalate (PETG). PLA notably demonstrates acceptable strain to failure of 2.6 % and a favorable increase in strength from 47 to 120 MPa when cooled. Testing of carbon fiber filled PLA (CF-PLA) finds a remarkable 250 % increase in strength, from 37 to 130 MPa. Both materials withstand 10 high-stress thermal cycles with mild strength gain, causing a loss of room temperature ductility in neat PLA but not CF-PLA. Dynamic Mechanical Analysis (DMA) indicates a β-transition at −20 to −40 °C, which correlates with the observed changes. These findings show AM thermoplastics are promising for use in cryogenic laboratory environments, and could be modified for use in production applications.

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, additive manufacturing technology, particularly in plastic component fabrication, has gained prominence. However, fundamental modelling of the influence of materials like ABS, PC, and PLA on tribological properties in fused deposition modeling (FDM) remains scarce, particularly in non-lubricated, oil-lubricated, and grease-lubricated modes. This experimental study systematically investigates the effects of material type, lubrication method, layer thickness, and infill density on FDM component tribology. A tribology analysis is conducted using a TRB3 tribometer. The results indicate a coefficient of friction (CoF) range between 0.04 and 0.2, generally increasing and decreasing with layer thickness and filler density. The lubrication impact hinges on the material surface texture. The study models the intricate relationships between these variables via full-factor analysis, showing a strong alignment between the modelled and measured friction coefficients (an average error of 3.83%). Validation tests on different materials affirm the model's reliability and applicability. [ABSTRACT FROM AUTHOR]

Four-dimensional printing is a process in which a 3D-printed object is intentionally transformed in response to an external stimulus such as temperature, which is useful when the final geometry of a 3D-printed part is not easily manufacturable. One method to demonstrate this is to print a part made of thin strips of material on a sheet of paper, heat the part, and allow it to cool. This causes the part to curl due to the difference in the thermal expansion coefficients of the paper and plastic. In an attempt to quantify the effect of different temperatures on various materials, samples of three common 3D printing filaments, acrylonitrile butadiene styrene (ABS), polyethylene terephthalate glycol (PETG), and polylactic acid (PLA), were heated at different temperatures (85 °C, 105 °C, and 125 °C) for intervals of 15 min and then allowed to cool until curling stopped. This heating and cooling cycle was repeated three times for each sample to determine if repeated heating and cooling influenced the curling. Each sample was filmed as it was cooling, which allowed the radius of curvature to be measured by tracking the uppermost point of the part, knowing the arc length, and calibrating the video based on a known linear length. After three cycles, all three materials showed a decrease in the radius of curvature (tighter curl) as heating temperature increased, with PLA showing the trend much more predominantly than ABS and PETG. Furthermore, for PETG and PLA, the radius of curvature decreased with each cycle at all temperatures, with the decrease being more significant from cycle 1 to 2 than cycle 2 to 3. Conversely, ABS only shared this trend at 125 °C. The findings of this work can provide guidelines to users on the temperature dosage for the mass manufacturing of complex geometries such as packaging, self-assembly robots, and drug delivery applications. [ABSTRACT FROM AUTHOR]

This article introduces a multi-objective optimization approach for determining the best 3D printing parameters (layer thickness and infill percentage) to efficiently produce PLA and ABS parts, extensively analyzing mechanical behavior under tests for different traits such as tensile strength, compression, flexural, impact, and hardness. The value analysis method is used to optimize settings that balance use value (Vi- represented by mechanical characteristics) and production cost (Cp). Findings reveal that the infill percentage significantly influences the Vi/Cp ratio for tensile, compression, and hardness tests, while flexural tests are influenced by layer thickness. Impact strength is influenced nearly equally by both factors, with material-specific variations. The desirability function proved useful for optimizing processes with multiple responses, identifying the optimal parameters for the FDM process: a layer thickness of 0.15 mm with 100% infill percentage for PLA, a layer thickness of 0.20 mm with 100% infill percentage for annealed PLA, and a layer thickness of 0.15 mm with 100% infill percentage for ABS. Overall, this study guides efficient 3D printing parameter selection through a technical-economic optimization based on value analysis. [ABSTRACT FROM AUTHOR]

In this research, multicellular structures using two materials acrylonitrile butadiene styrene and Polylactic Acid in various geometries were investigated. At the beginning of this research, samples with a thickness of 1 mm were made using 3D printers. These samples were subjected to quasi-static loading and force-displacement curves were extracted for them. Subsequently, LS-DYNA finite element software was used to simulate the structures under quasi-static loading and the tested samples in the experimental mode were simulated. After comparing the experimental and numerical results and ensuring the correctness of the simulations, different states were simulated and a total of 6 experimental samples and 30 numerical samples were examined. The results obtained in this research showed that with the increase in the number of cells, the amount of specific energy absorption of the samples increased. It was also found that in the samples with square cores, the number of cores in each row and column corresponds to the number of force peaks and the number of peaks increases with the increase of cores. [ABSTRACT FROM AUTHOR]

This study explores the enhancement of mechanical properties in 3D-printed polylactic acid and acrylonitrile-butadiene-styrene parts through ultrasonic treatment. Tensile samples were fabricated using fused filament fabrication with varying infill percentages (60% and 100%) and layer thicknesses (0.15 mm and 0.30 mm). Post-processing involved a high-power ultrasonic treatment for 2 seconds, followed by tensile testing. The results demonstrated an average 10% increase in tensile strength for both acrylonitrile-butadiene-styrene and polylactic acid after ultrasonic treatment, with the highest tensile strengths measured at approximately 41 MPa and 38 MPa, respectively. However, strain at fracture experienced a decline, except in the samples with an infill percentage of 100 and a number of layers of 10. Scanning electron microscopy revealed dimensional changes and raster merging, more pronounced in 60% and 100% infill samples, respectively. The study employed a comprehensive full factorial design of experiments and finite element simulation for ultrasonic treatment setup design. The interaction of 3D printing and ultrasonic treatment parameters was investigated, with the infill percentage exhibiting the most substantial impact on the ultimate tensile strength. The results highlight the potential of ultrasonic treatment to enhance mechanical properties, reduce defects, and improve the structural integrity of 3D-printed components. [ABSTRACT FROM AUTHOR]

3D printing is one of the most portentous technologies for the time being. Recently, 3D printing has progressed remarkably and is expected to proceed in numerous applications, such as automotive, medical, wind turbine, and aerospace applications. 3D printing technology opens the door to enhancing and optimizing several applications. Although of such advancement, there is still a lack of the tribological research investigations in this area. This work is devoted to studying the tribological properties of 3D printed polymers (ABS, PLA, Co-polyester, and PCL) for utilization in a wide range of applications, such as medical, automotive, and various tribological applications. The test specimens were printed using fused deposition modeling (FDM) technology. The tribological characteristics of 3D printed specimens were evaluated using a pin-on-disc tester. Vicker's hardness tester was used to determine the specimens' hardness. Scanning electron microscopy (SEM) with backscattering was used to examine the worn surfaces of samples. Based on the findings of the current investigation, it was discovered that 3D printing technology enhanced the bonding strength and wear resistance of the tested specimens. Furthermore, the 3D-printed polymers (ABS, PLA, Co-polyester, and PCL) produced varying friction coefficient (high and low) values at acceptable wear resistance making them suitable for a wide range of applications. The samples that were printed using PLA and co-polyester had the lowest coefficients of friction (0.3) while the samples that were printed using ABS and PCL had the greatest coefficients of friction (0.4) and (0.39) respectively.

3D printing is widely used method. In the term of developing of components for electronic devices, it is important to provide the good physical properties of the used dielectric. The main parameters are optional and stable value of the relative permittivity and the minimum dielectric losses of the material. The paper is focused on testing of loss factor and relative permittivity of following materials: polylactic acid (PLA, in two dye modifications), polyethylene terephthalateglycol (PET- G) and acrylonitrile butadiene styrene (ABS) in the frequency range of 1-100 MHz. It was proven, that the values of permittivity of the tested materials were 2.9-4.2 and loss factor 0.8-4%. Concerning relative permittivity, the tendency to mild linear drop of relation was observed by increasing frequency, especially expressed in PLA materials. In loss factor, PLA materials displayed increasing values with increasing frequency, whereas the declining curve was observed in PET-G. Absolute value of ABS loss factor varied between 0.9-1.5%. The reasonable influence of added dyes was found out.

In recent years, there has been a growing interest in the field of 3D printing technology. Among the various technologies available, fused deposition modeling (FDM) has emerged as the most popular and widely used method. However, achieving optimal results with FDM presents a significant challenge due to the selection of appropriate process parameters. Therefore, the objective of this research was to investigate the impact of process parameters on the tribological and frictional behavior of acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) 3D-printed parts. The design of experiments (DOE) technique was used considering the input design parameters (infill percentage and layer thickness) as variables. The friction coefficient values and the wear were determined by experimental testing of the polymers on a universal tribometer employing plane friction coupling. Multi-response optimization methodology and analysis of variance (ANOVA) were used to highlight the dependency between the coefficient of friction, surface roughness parameters, and wear on the process parameters. The optimization analysis revealed that the optimal 3D printing input parameters for achieving the minimum coefficient of friction and linear wear were found to be an infill percentage of 50% and layer thickness of 0.1 mm (for ABS material), and an infill percentage of 50%, layer thickness of 0.15 mm (for PLA material). The suggested optimization methodology (which involves minimizing the coefficient of friction and cumulative linear wear) through the optimized parameter obtained provides the opportunity to select the most favorable design conditions contributing to a more sustainable approach to manufacturing by reducing overall material consumption. [ABSTRACT FROM AUTHOR]

Functionally graded materials (FGM) have attracted considerable attention in the field of composite materials and rekindled interest in research on composite materials due to their unique mechanical response achieved through material design and optimization. Compared to conventional composites, FGMs offer several advantages and exceptional properties, including improved deformation resistance, improved toughness, lightness properties, and excellent recoverability. This study focused on the production of functionally graded (FG) polymer materials by the additive manufacturing (AM) method. FG structures were produced by the fused deposition modeling (FDM) method using acrylonitrile benzidine styrene (ABS) and polylactic acid (PLA) materials, and tensile tests were performed according to ASTM D638. The effects of different layer thicknesses, volume ratios, and total thicknesses on mechanical behavior were investigated. The tensile standard of materials produced by additive manufacturing introduces geometric differences. Another motivation in this study is to reveal the differences between the results according to the ASTM standard. In addition, tensile tests were carried out by producing single-layer samples at certain volume ratios to create a numerical model with the finite element method to verify the experimental data. As a result of this study, it is presented that the FG structure produced with FDM improves mechanical behavior. [ABSTRACT FROM AUTHOR]

Material extrusion (ME) is an additive manufacturing technique capable of producing functional parts, and its use in multi-material fabrication requires further exploration and expansion. The effectiveness of material bonding is one of the main challenges in multi-material fabrication using ME due to its processing capabilities. Various procedures for improving the adherence of multi-material ME parts have been explored, such as the use of adhesives or the post-processing of parts. In this study, different processing conditions and designs were investigated with the aim of optimizing polylactic acid (PLA) and acrylonitrile–butadiene–styrene (ABS) composite parts without the need for pre- or post-processing procedures. The PLA-ABS composite parts were characterized based on their mechanical properties (bonding modulus, compression modulus, and strength), surface roughness (Ra, Rku, Rsk, and Rz), and normalized shrinkage. All process parameters were statistically significant except for the layer composition parameter in terms of Rsk. The results show that it is possible to create a composite structure with good mechanical properties and acceptable surface roughness values without the need for costly post-processing procedures. Furthermore, the normalized shrinkage and the bonding modulus were correlated, indicating the ability to utilize shrinkage in 3D printing to improve material bonding. [ABSTRACT FROM AUTHOR]

The purpose of this study is determine the mechanical properties of PLA-Hap-Chitosan and ABS-HAp-Chitosan composites. Poly lactic acid (PLA) and acrylonitrile butdie styrene (ABS) are polymers that can be applied in the biomedical field because they the to decompose naturally in the human body. To streng and not make the body wear out, a ceramic element that has bioactive, biodegradable and biocompatible properties is added, namely hydrochiapatite (HAp). In addition to hydroxyapatite, chitosan is also added as a natural element that has as an anti-bacterial. The materials used are PLA and ABS with variations using HAp powder and chitosan. The process of making this composite uses an injection molding process with a temperature of 190oC on PLA and 250oC on ABS. The results showed that the addition of HAp and chitosan powder to PLA and ABS caused a decrease in the mechanical properties of the composite, this was due to the difference in polarity which led to the formation of agglomeration in the composite and resulted in poor interactions, causing the mechanical properties of the composite to decrease. The maximum mechanical properties are aimed at the composition of PLA-Hap-Chitosan 90-0-10 and the minimum is PLA-Hap-Chitosan 90-2-8. Meanwhile, for the ABS-HAp-Chitosan composite, the maximum mechanical properties were aimed at the ABS-HAp-Chitosan 90-8-2 composition and the minimum for the ABS-Hap-Chitosan 90-0-10 composition.

The manufacturing of machine parts with additive methods (AM) is of significant importance in modern industry. The development of 3D printers and all 3D printing technology is impressive. The ability to make parts quickly and relatively cheaply with AM gives excellent opportunities in terms of e.g., shortening the production preparation time. Proper selection of printing parameters allows for a significant reduction of printing time and production costs. Unfortunately, this has different consequences. Due to the course of the printing process and the parameters that can be set, the same product produced with different parameters has different mechanical properties - mainly different strength. This paper presents the impact of 3D printing parameters on the strength of manufactured parts. Strength tests were carried out on samples made in accordance with DIN EN ISO 527-1:2019. The samples were printed in technology FDM from three different materials, i.e. PLA (completely biodegradable), PETG (recycled material), and Smart ABS (material with minimal shrinkage). The tested samples were made in three levels of print filling - 10%, 30%, and 60% and with different types of filling - line, mesh, and honeycomb. A series of static tensile tests were carried out to determine the strength of the samples produced with different printing parameters. Thanks to the obtained test results, it is possible to select the optimal printing parameters depending on the forecast load of the manufactured parts

The use of components obtained through the additive manufacturing (AM) technique has become increasingly widespread in recent years, playing a central role in industrial production, and in particular in some fields such as automotive, biomedical, aerospace and electronics. Among all AM techniques, FDM (Fused Deposition Modelling) represents the most used printing technique to produce polymeric and composite components, thanks to the flexible printing process, the low cost and the diversity of the materials adopted. The aim of the present work concerns the comparison between the mechanical properties of three plastic materials printed with the FDM technique (polylactic acid PLA, polyethylene terephthalate glycol-modified PETG and Acrylonitrile-butadiene-styrene ABS) using an Original Prusa i3 MK3S, by varying the raster angle between 0�, 45� and 90� degrees. Infrared Thermography has been adopted to monitor the temperature evolution during static tensile tests and to assess stress level that can initiate damage within the material. Failure analysis was performed to correlate the mechanical behaviour with the microstructural characteristics of the materials

Additive manufacturing or 3D printing technologies might advance the fabrication sector of personalised biomaterials with high-tech precision. The selection of optimal precursor materials is considered the first key-step for the development of new printable filaments destined for the fabrication of products with diverse orthopaedic/dental applications. The selection route of precursor materials proposed in this study targeted two categories of materials: prime materials, for the polymeric matrix (acrylonitrile butadiene styrene (ABS), polylactic acid (PLA)); and reinforcement materials (natural hydroxyapatite (HA) and graphene nanoplatelets (GNP) of different dimensions). HA was isolated from bovine bones (HA particles size < 40 μm, <100 μm, and >125 μm) through a reproducible synthesis technology. The structural (FTIR-ATR, Raman spectroscopy), morphological (SEM), and, most importantly, in vitro (indirect and direct contact studies) features of all precursor materials were comparatively evaluated. The polymeric materials were also prepared in the form of thin plates, for an advanced cell viability assessment (direct contact studies). The overall results confirmed once again the reproducibility of the HA synthesis method. Moreover, the biological cytotoxicity assays established the safe selection of PLA as a future polymeric matrix, with GNP of grade M as a reinforcement and HA as a bioceramic. Therefore, the obtained results pinpointed these materials as optimal for future composite filament synthesis and the 3D printing of implantable structures. [ABSTRACT FROM AUTHOR]

Since the advent of polymeric materials, many structures have always been built for engineering purposes. On the one hand, the emergence of composites containing glass fibers has had a significant impact on reducing the weight of structures in various industries. On the other hand, with the advent of 3D printers, many limitations for the geometry of engineering structures were removed. In this research, due to the wide application of these two sciences, a new type of composite absorbers has been introduced. The presented absorbers have glass fiber-reinforced polymer cores (GFRP) or low-density polyethylene cores (LDPE), the shells of each sample are made of PLA or ABS. In this study, 24 different samples were tested under quasi-static loading. The samples were examined in three different groups. In the first group, no cores were used, but in the second group, GFRP cores were used, and in the third group, LDPE cores were used. Triangular, trapezoidal, semielliptical, and square sections were studied, and the results showed that the lowest maximum force was related to samples with semielliptical cross section, then the maximum force increased by changing the cross section from triangular to trapezoidal and then to a square. In addition, the maximum force was higher in the GFRP core than in the LPDE core. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) printer usage in household and school settings has raised health concerns regarding chemical and particle emission exposures during operation. Although the composition of 3D printer emissions varies depending on printer settings and materials, little is known about the impact that emissions from different filament types may have on respiratory health and underlying cellular mechanisms. In this study, we used an in vitro exposure chamber system to deliver emissions from two popular 3D-printing filament types, acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA), directly to human small airway epithelial cells (SAEC) cultured in an air–liquid interface during 3D printer operation. Using a scanning mobility particle sizer (SMPS) and an optical particle sizer (OPS), we monitored 3D printer particulate matter (PM) emissions in terms of their particle size distribution, concentrations, and calculated deposited doses. Elemental composition of ABS and PLA emissions was assessed using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX). Finally, we compared the effects of emission exposure on cell viability, inflammation, and metabolism in SAEC. Our results reveal that, although ABS filaments emitted a higher total concentration of particles and PLA filaments emitted a higher concentration of smaller particles, SAEC were exposed to similar deposited doses of particles for each filament type. Conversely, ABS and PLA emissions had distinct elemental compositions, which were likely responsible for differential effects on SAEC viability, oxidative stress, release of inflammatory mediators, and changes in cellular metabolism. Specifically, while ABS- and PLA-emitted particles both reduced cellular viability and total glutathione levels in SAEC, ABS emissions had a significantly greater effect on glutathione relative to PLA emissions. Additionally, pro-inflammatory cytokines including IL-1β, MMP-9, and RANTES were significantly increased due to ABS emissions exposure. While IL-6 and IL-8 were stimulated in both exposure scenarios, VEGF was exclusively increased due to PLA emissions exposures. Notably, ABS emissions induced metabolic perturbation on amino acids and energy metabolism, as well as redox-regulated pathways including arginine, methionine, cysteine, and vitamin B3 metabolism, whereas PLA emissions exposures caused fatty acid and carnitine dysregulation. Taken together, these results advance our mechanistic understanding of 3D-printer-emissions-induced respiratory toxicity and highlight the role that filament emission properties may play in mediating different respiratory outcomes.

Polylactic Acid (PLA) and Acrylonitrile–Butadiene–Styrene (ABS) are commonly used polymers in 3D printing for biomedical applications. Dental Pulp Stem Cells (DPSCs) are an accessible and proliferative source of stem cells with significant differentiation potential. Limited knowledge exists regarding the biocompatibility and genetic safety of ABS and PLA when in contact with DPSCs. This study aimed to investigate the impact of PLA and ABS on the adhesion, proliferation, osteogenic differentiation, genetic stability, proteomics, and immunophenotypic profile of DPSCs. A total of three groups, 1- DPSC-control, 2- DPSC+ABS, and 3- DPSC+PLA, were used in in vitro experiments to evaluate cell morphology, proliferation, differentiation capabilities, genetic stability, proteomics (secretome), and immunophenotypic profiles regarding the interaction between DPSCs and polymers. Both ABS and PLA supported the adhesion and proliferation of DPSCs without exhibiting significant cytotoxic effects and maintaining the capacity for osteogenic differentiation. Genetic stability, proteomics, and immunophenotypic profiles were unaltered in DPSCs post-contact with these polymers, highlighting their biosafety. Our findings suggest that ABS and PLA are biocompatible with DPSCs and demonstrate potential in dental or orthopedic applications; the choice of the polymer will depend on the properties required in treatment. These promising results stimulate further studies to explore the potential therapeutic applications in vivo using prototyped polymers in personalized medicine.

3D printing is a widely used method. In terms of developing components for electronic devices, it is important to provide good physical properties of the used dielectric. The main parameters are the optional and stable value of the relative permittivity and the minimum dielectric losses of the material. The paper focuses on testing the loss factor and relative permittivity of the following materials: polylactic acid (PLA, in two dye modifications), polyethylene terephthalate glycol (PET-G) and acrylonitrile butadiene styrene (ABS) in the frequency range of 1–100 MHz. It was proven that the values of permittivity of the tested materials were 2.9–4.2 and the loss factor was 0.8–4%. Concerning the relative permittivity, the tendency to show a mild linear drop was observed by increasing the frequency, especially expressed in the PLA materials. With the loss factor, the PLA materials displayed increasing values with an increasing frequency, whereas a declining curve was observed in the PET-G materials. The absolute value of the ABS loss factor varied between 0.9–1.5%. The reasonable influence of added dyes was elucidated upon. [ABSTRACT FROM AUTHOR]

3D printing is one of the most portentous technologies for the time being. Recently, 3D printing has progressed remarkably and is expected to proceed in numerous applications, such as automotive, medical, wind turbine, and aerospace applications. 3D printing technology opens the door to enhancing and optimizing several applications. Although of such advancement, there is still a lack of the tribological research investigations in this area. This work is devoted to studying the tribological properties of 3D printed polymers (ABS, PLA, Co-polyester, and PCL) for utilization in a wide range of applications, such as medical, automotive, and various tribological applications. The test specimens were printed using fused deposition modeling (FDM) technology. The tribological characteristics of 3D printed specimens were evaluated using a pin-on-disc tester. Vicker's hardness tester was used to determine the specimens' hardness. Scanning electron microscopy (SEM) with backscattering was used to examine the worn surfaces of samples. Based on the findings of the current investigation, it was discovered that 3D printing technology enhanced the bonding strength and wear resistance of the tested specimens. Furthermore, the 3D-printed polymers (ABS, PLA, Co-polyester, and PCL) produced varying friction coefficient (high and low) values at acceptable wear resistance making them suitable for a wide range of applications. The samples that were printed using PLA and co-polyester had the lowest coefficients of friction (0.3) while the samples that were printed using ABS and PCL had the greatest coefficients of friction (0.4) and (0.39) respectively. [ABSTRACT FROM AUTHOR]

The main objective of this work was to investigate the mechanical properties of additive manufactured (AM) polymeric parts (polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS)) reinforced by different types of fibres. Natural (jute and curauá) and synthetic (glass) fibre fabrics were laminated on the outer sides of the AM parts by using an epoxy resin. The reinforcement was applied to the AM parts as 1 and 2 layers for each fibre type. The mechanical characterization of the AM-reinforced composites was performed through tensile and flexural tests. It was found that the addition of the reinforcement fibres improved the mechanical properties of the AM parts for both materials tested. In general, the glass fibre–reinforced specimens presented better mechanical properties when compared to the natural fibre–reinforced AM parts. The curauá fibre–reinforced specimens presented improved performance when compared to the jute composites and matched the mechanical properties of the 1-layer glass fibre–reinforced AM specimens. The failure modes significantly varied as a function of the material. The PLA specimens showed a brittle failure, while the ABS specimens presented delamination in the resin/printed part interface. Adding different fibre fabrics to 3D-printed materials may be a promising innovation in order to improve their mechanical properties and these improvements might enable these materials to serve for high load bearing purposes. [ABSTRACT FROM AUTHOR]

The impact of radiation on polymer materials, and consequently on their mechanical and physical properties, is a burgeoning field of research. This research assesses the dosimetric, mechanical, and thermal characteristics of Acrylonitrile Butadiene Styrene (ABS) and Polylactic Acid (PLA) materials developed through plastic injection molding as possible alternatives to commercial bolus used in radiotherapy. The materials were thoroughly compared with the commercial bolus material, EXAFLEX, by various tests such as Hounsfield Unit (HU) Analysis, Radiation Transmittance, Thermogravimetric Analysis (TGA), Thermomechanical Analysis (TMA), and Fourier Transform Infrared Spectroscopy (FTIR). The research indicates that ABS and PLA materials have similar radiological qualities to EXAFLEX, showing constant surface and accumulation area doses. Minor differences are seen deeper inside the phantom, indicating a stable tissue equivalency. ABS demonstrated strong resistance to radiation-induced chemical modifications, but PLA exhibited susceptibility to molecular changes. The TMA findings showed that radiation caused a decrease in softening temperatures and an increase in the coefficient of thermal expansion for both ABS and PLA, indicating changes in their thermal stability and mechanical characteristics after irradiation. The study highlights the potential of ABS and PLA materials made through plastic injection molding as efficient and safety substitutes for commercial bolus materials, particularly for large area irradiation. This requires more research into their clinical uses and consequences. • Assessed ABS and PLA as radiotherapy bolus alternatives, comparing to commercial EXAFLEX. • Employed tests including HU Analysis, Radiation Transmittance, and TGA to compare materials. • Found ABS and PLA show similar radiological qualities to EXAFLEX with stable doses. • ABS resists radiation-induced changes; PLA shows susceptibility to molecular alterations. • Radiation affects thermal stability and mechanical properties of ABS and PLA. [ABSTRACT FROM AUTHOR]

In recent years, additive manufacturing technology, particularly in plastic component fabrication, has gained prominence. However, fundamental modelling of the influence of materials like ABS, PC, and PLA on tribological properties in fused deposition modeling (FDM) remains scarce, particularly in non-lubricated, oil-lubricated, and grease-lubricated modes. This experimental study systematically investigates the effects of material type, lubrication method, layer thickness, and infill density on FDM component tribology. A tribology analysis is conducted using a TRB3 tribometer. The results indicate a coefficient of friction (CoF) range between 0.04 and 0.2, generally increasing and decreasing with layer thickness and filler density. The lubrication impact hinges on the material surface texture. The study models the intricate relationships between these variables via full-factor analysis, showing a strong alignment between the modelled and measured friction coefficients (an average error of 3.83%). Validation tests on different materials affirm the model’s reliability and applicability.

Four-dimensional printing is a process in which a 3D-printed object is intentionally transformed in response to an external stimulus such as temperature, which is useful when the final geometry of a 3D-printed part is not easily manufacturable. One method to demonstrate this is to print a part made of thin strips of material on a sheet of paper, heat the part, and allow it to cool. This causes the part to curl due to the difference in the thermal expansion coefficients of the paper and plastic. In an attempt to quantify the effect of different temperatures on various materials, samples of three common 3D printing filaments, acrylonitrile butadiene styrene (ABS), polyethylene terephthalate glycol (PETG), and polylactic acid (PLA), were heated at different temperatures (85 °C, 105 °C, and 125 °C) for intervals of 15 min and then allowed to cool until curling stopped. This heating and cooling cycle was repeated three times for each sample to determine if repeated heating and cooling influenced the curling. Each sample was filmed as it was cooling, which allowed the radius of curvature to be measured by tracking the uppermost point of the part, knowing the arc length, and calibrating the video based on a known linear length. After three cycles, all three materials showed a decrease in the radius of curvature (tighter curl) as heating temperature increased, with PLA showing the trend much more predominantly than ABS and PETG. Furthermore, for PETG and PLA, the radius of curvature decreased with each cycle at all temperatures, with the decrease being more significant from cycle 1 to 2 than cycle 2 to 3. Conversely, ABS only shared this trend at 125 °C. The findings of this work can provide guidelines to users on the temperature dosage for the mass manufacturing of complex geometries such as packaging, self-assembly robots, and drug delivery applications.

This article introduces a multi-objective optimization approach for determining the best 3D printing parameters (layer thickness and infill percentage) to efficiently produce PLA and ABS parts, extensively analyzing mechanical behavior under tests for different traits such as tensile strength, compression, flexural, impact, and hardness. The value analysis method is used to optimize settings that balance use value (Vi- represented by mechanical characteristics) and production cost (Cp). Findings reveal that the infill percentage significantly influences the Vi/Cp ratio for tensile, compression, and hardness tests, while flexural tests are influenced by layer thickness. Impact strength is influenced nearly equally by both factors, with material-specific variations. The desirability function proved useful for optimizing processes with multiple responses, identifying the optimal parameters for the FDM process: a layer thickness of 0.15 mm with 100% infill percentage for PLA, a layer thickness of 0.20 mm with 100% infill percentage for annealed PLA, and a layer thickness of 0.15 mm with 100% infill percentage for ABS. Overall, this study guides efficient 3D printing parameter selection through a technical-economic optimization based on value analysis.

The manufacturing of machine parts with additive methods (AM) is of significant importance in modern industry. The development of 3D printers and all 3D printing technology is impressive. The ability to make parts quickly and relatively cheaply with AM gives excellent opportunities in terms of e.g., shortening the production preparation time. Proper selection of printing parameters allows for a significant reduction of printing time and production costs. Unfortunately, this has different consequences. Due to the course of the printing process and the parameters that can be set, the same product produced with different parameters has different mechanical properties – mainly different strength. This paper presents the impact of 3D printing parameters on the strength of manufactured parts. Strength tests were carried out on samples made in accordance with DIN EN ISO 527-1:2019. The samples were printed in technology FDM from three different materials, i.e. PLA (completely biodegradable), PETG (recycled material) and Smart ABS (material with minimal shrinkage). The tested samples were made in three levels of print filling – 10, 30 and 60% and with different types of filling – line, mesh and honeycomb. A series of static tensile tests were carried out to determine the strength of the samples produced with different printing parameters. Thanks to the obtained test results, it is possible to select the optimal printing parameters depending on the forecast load of the manufactured parts. The manufacturing of machine parts with additive methods (AM) is of significant importance in modern industry. The development of 3D printers and all 3D printing technology is impressive. The ability to make parts quickly and relatively cheaply with AM gives excellent opportunities in terms of e.g., shortening the production preparation time. Proper selection of printing parameters allows for a significant reduction of printing time and production costs. Unfortunately, this has different consequences. Due to the course of the printing process and the parameters that can be set, the same product produced with different parameters has different mechanical properties – mainly different strength. This paper presents the impact of 3D printing parameters on the strength of manufactured parts. Strength tests were carried out on samples made in accordance with DIN EN ISO 527-1:2019. The samples were printed in technology FDM from three different materials, i.e. PLA (completely biodegradable), PETG (recycled material) and Smart ABS (material with minimal shrinkage). The tested samples were made in three levels of print filling – 10, 30 and 60% and with different types of filling – line, mesh and honeycomb. A series of static tensile tests were carried out to determine the strength of the samples produced with different printing parameters. Thanks to the obtained test results, it is possible to select the optimal printing parameters depending on the forecast load of the manufactured parts. [ABSTRACT FROM AUTHOR]

The objective of the present work is to evaluate the influence of material color on mechanical properties of fused deposition modeling (FDM) parts. The performance of the products is evaluated by testing eight different colors of acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) material in terms of tensile strength, compressive strength, and flexural strength. The analysis of data shows a significant difference in mechanical characteristics of prints depending on filament color. For different colors, these three strengths almost follow the same rising and falling tendency. In order to explore the relationship between mechanical strengths and filament colors, the color-mixing theory and the least-squares method are adopted to fit the best ratio coefficients of different color combinations. Results are presented showing that the strength value (e.g., tensile) of the mixed color can be evaluated through that of primary colors by fitting the other strength (e.g., compressive or flexural). It is shown that the predicted value is always no more than 7% error compared with the actual strength, in spite of two-color or three-color mixtures. An additional confirmation test with seven colored PLA filaments from different suppliers was conducted to focus on the extensibility. The outcomes show the maximum fitting errors of strengths for mixed colors in all cases are within 5%, proving the effectiveness and applicability of this predicted approach. This study can bring a detailed analysis that enables better estimation of the function of material color and contributes to improving the property of FDM printed products for consumers by choosing the suitable filament color. [ABSTRACT FROM AUTHOR]

The use of components obtained through the additive manufacturing (AM) technique has become increasingly widespread in recent years, playing a central role in industrial production, and in particular in some fields such as automotive, biomedical, aerospace and electronics. Among all AM techniques, FDM (Fused Deposition Modelling) represents the most used printing technique to produce polymeric and composite components, thanks to the flexible printing process, the low cost and the diversity of the materials adopted. The aim of the present work concerns the comparison between the mechanical properties of three plastic materials printed with the FDM technique (polylactic acid PLA, polyethylene terephthalate glycol-modified PETG and Acrylonitrile-butadiene-styrene ABS) using an Original Prusa i3 MK3S, by varying the raster angle between 0°, 45° and 90° degrees. Infrared Thermography has been adopted to monitor the temperature evolution during static tensile tests and to assess stress level that can initiate damage within the material. Failure analysis was performed to correlate the mechanical behaviour with the microstructural characteristics of the materials. [ABSTRACT FROM AUTHOR]

Plastic gear applications are rapidly increasing in transmission systems in automotive, domestic and kitchen machineries. Biopolymer gears are now being preferred over polymer gears due to its biodegradable properties. Hence, a comparative investigation of wear characteristics between polymer and biopolymer gears is studied. Injection molded biopolymer, PLA (polylactic acid) gear and polymer, ABS (acrylonitrile butadiene styrene) gear have been fabricated with appropriate properties. Gears are experimentally tested for the period of 3 h at three different rotational speeds (500, 1000 & 1500 rpm) with and without load (1 kg). Wear debris, material loss, thermal damage and microstructure surface condition monitoring have been investigated. PLA presents better adhesive wear resistance and shows thermal deformation and tooth breakage. Biopolymer gives better thermal and wear resistance than polymer gear. At low rotational speed of 500 rpm under no-loading condition, both PLA and ABS show higher weight loss and wear rate due to thermal damage occurred due to gear pump effect. Whereas when load is applied, PLA shows wear loss at all rotational speeds due to inferior thermal conductivity and ABS shows wear loss at high rotational speeds of 1000 rpm or 1500 rpm due to loading effect. [ABSTRACT FROM AUTHOR]