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This study aims to discuss the effect of carbon nanotubes (CNTs) on the mechanical properties of acrylonitrile–butadiene–styrene (ABS) composites fabricated by additive manufacturing (AM). Insight into the energy-dissipation mechanisms introduced and/or enhanced by the addition of CNTs is presented in this study.

ABS/CNT filaments were fabricated with different concentrations of CNTs. Using a fused deposition modeling approach, unidirectional specimens were printed using a MakerBot Replicator 2X (MakerBot Industries, Brooklyn, NY, USA). Specimens were tested under static and dynamic conditions, with the loading coinciding with the printing direction, to determine elastic modulus, strength and viscoelastic properties.

A CNT reinforcing effect is evident in a 37 per cent increase in elastic modulus. Likewise, the strength of the composite increases by up to 30 per cent with an increase in weight fraction of CNTs. At low dynamic strain amplitudes (0.05 per cent), a correlation between dissipated strain energy of the butadiene phase and strength of the composite is found such that less dissipation, from constraint of the butadiene particles by the CNTs, leads to higher strength of the composite. At higher dynamic strains, the presence of a high concentration of CNT leads to increased energy dissipation, with a maximum measured value of 24 per cent higher loss factor compared to baseline specimens. Because the trend of the composite behavior is similar (with a higher absolute value) to that of neat ABS, this study’s results indicate that well-established polymer/CNT dissipation mechanisms (such as stick-slip) are not significant, but that the CNTs amplify the dissipation of the ABS matrix by formation of crazes through stress concentrations.

This study provides knowledge of the dissipation behavior in additively manufactured ABS/CNT composites and provides insight into the expansion to new printable materials for dynamics applications.

This study aims to comprehensively investigate the process-structure-property correlation of acrylonitrile butadiene styrene (ABS) parts manufactured by the overheat material extrusion (Mex) method. This study considers the relationships between the tensile and impact strength with temperature profiles, mesostructures and fracture behaviors of the ABS-printed parts.

The overheat printing condition was generated by using the highest possible printing temperature of the Mex printer used in this study together with cooling fan turned off. Temperature profiles of the polymer rasters were measured to characterize the diffusion time of the deposited rasters. Thermogravimetric analysis, differential scanning calorimetry and melt flow index were performed to study the thermal properties of the ABS feedstock. The mesostructures of the printed ABS samples were characterized by using an optical microscope, while their fracture surface was investigated using a field emission scanning electron microscope. The authors performed the tensile and impact tests following ASTM D3039 and D256-10A, respectively.

The use of the overheat Mex printing could offer better raster diffusion with reduced cooling rate and prolonged diffusion time. Consequently, the overheat printed ABS parts possessed a porosity as low as 1.35% with an increase in the weld length formed between the adjacent rasters of up to 62.5%. More importantly, the overheat printed ABS parts exhibited an increase of up to 70%, 84% and 30% in tensile strain at break, tensile toughness and impact strength, respectively, compared to their normal printed counterparts.

This study provides a facile but effective approach to fabricate highly dense and strong polymeric parts printed by Mex method for end-use applications.

This study aims to evaluate and compare the macroscopic properties of commercial acrylonitrile-butadiene-styrene (ABS) processed by two different types of additive manufacturing (AM) machines. The focus is also on the effect of multiple closed-loop recycling of ABS.

A conventional direct-drive, Cartesian-type machine and a Bowden, Delta-type machine with an infrared radiant heating system are used to manufacture test specimens molded in ABS. Afterward, multiple closed-loop recycling cycles are conducted, involving consecutive AM (four times) and recycling (three times). The rheological, mechanical, morphological and physicochemical properties are investigated.

The type of machine affects the quality of the produced parts. The machine containing an infrared radiant system in a temperature-controlled chamber produces parts showing higher mechanical properties and filling fraction, although it increases the yellowing. Closed-loop recycling of ABS for AM is applicable for at least two cycles, inducing a slight increase in tensile modulus (ca. 5%) and in tensile strength (ca. 13%) and a decrease in the impact strength (ca. 14%) and melt viscosity. An increase in the filling fraction of the AM parts promotes an increase in tensile strength and tensile modulus, although it does not influence the impact strength. Furthermore, multiple closed-loop recycling does not affect the overall chemical structure of ABS.

Controlling the environmental temperature and using infrared radiant heating during AM of ABS improves the quality of the produced parts. Closed-loop recycling of ABS used in AM is feasible up to at least two recycling steps, supporting the implementation of a circular economy for polymer-based AM.

This study shows original results regarding the assessment of the effect of different types of AM machines on the main end-use properties of ABS parts and the influence of multiple closed-loop recycling on the characteristics of ABS fabricated by the most suited AM machine with an infrared radiant heating system and a temperature-controlled environment.

The purpose of the present paper is to quantify and analyze the strain-rate dependence of the yield stress for both unfilled acrylonitrile-butadiene-styrene (ABS) and short carbon fiber-reinforced ABS (CF-ABS) materials, fabricated via material extrusion additive manufacturing (ME-AM). Two distinct and opposite infill orientation angles were used to attain anisotropy effects.

Tensile test samples were printed with two different infill orientation angles. Uniaxial tensile tests were performed at five different constant linear strain rates. Apparent densities were measured to compensate for the voided structure. Scanning electron microscope fractography images were analyzed. An Eyring-type flow rule was evaluated for predicting the strain-rate-dependent yield stress.

Anisotropy was detected not only for the yield stresses but also for its strain-rate dependence. The short carbon fiber-filled material exhibited higher anisotropy than neat ABS material using the same ME-AM processing parameters. It seems that fiber and molecular orientation influence the strain-rate dependence. The Eyring-type flow rule can adequately describe the yield kinetics of ME-AM components, showing thermorheologically simple behavior.

A polymer’s viscoelastic behavior is paramount to be able to predict a component’s ultimate failure behavior. The results in this manuscript are important initial findings that can help to further develop predictive numerical tools for ME-AM technology. This is especially relevant because of the inherent anisotropy that ME-AM polymer components show. Furthermore, short carbon fiber-filled ABS enhanced anisotropy effects during ME-AM, which have not been measured previously.

The purpose of the experimental investigation was to optimize the process parameters of the fused deposition modeling (FDM) technique. The optimization of the process was performed to identify the relationship between the chosen factors and the tensile strength of acrylonitrile butadiene styrene (ABS) and carbon fiber polylactic acid (PLA) thermoplastic material, FDM printed specimens. The relationship was demonstrated by using the linear experimental model analysis, and a prediction expression was established. The developed prediction expression can be used for the prediction of tensile strength of selected thermoplastic materials at a 95% confidence level.

The Taguchi L9 experimental methodology was used to plan the total number of experiments to be performed. The process parameters were chosen as three at three working levels. The working range of chosen factors was the printing speed (60, 80 and 100mm/min), 40%, 60% and 80% as the infill density and 0.1mm, 0.2mm and 0.3mm as the layer thickness. The fused deposition modeling process parameters were optimized to get the maximum tensile strength in FDM printed ABS and carbon fiber PLA thermoplastic material specimens.

The optimum condition was achieved by the process optimization, and the desired results were obtained. The maximum desirability was achieved as 0.98 (98%) for the factors, printing speed 100mm/min, infill density 60mm and layer thickness 0.3mm. The strength of the ABS specimen was predicted to be 23.83MPa. The observed strength value was 23.66MPa. The maximum desirability was obtained as 1 (100%) for the factors, printing speed 100mm/min, infill density 60mm and layer thickness 0.2mm. The strength of the carbon fiber PLA specimen was predicted to be 26.23MPa, and the obtained value was 26.49MPa.

The research shows the useful process parameters and their suitable working conditions to print the tensile specimens of the ABS and carbon fiber PLA thermoplastics by using the fused deposition modeling technique. The process was optimized to identify the most influential factor, and the desired optimum condition was achieved at which the maximum tensile strength was reported. The produced prediction expression can be used to predict the tensile strength of ABS and carbon fiber PLA filaments.

The results obtained from the experimental investigation are useful to get an insight into the FDM process and working limits to print the parts by using the ABS and carbon fiber PLA material for various industrial and structural applications.

The results will be useful in choosing the suitable thermoplastic filament for the various prototyping and structural applications. The products that require freedom in design and are difficult to produce by most of the conventional techniques can be produced at low cost and in less time by the fused deposition modeling technique.

The process optimization shows the practical exposures to state an optimum working condition to print the ABS and carbon fiber PLA tensile specimens by using the FDM technique. The carbon fiber PLA shows better strength than ABS thermoplastic material.

This study aims to investigate the mechanical, thermal, melt-flow and morphological behavior of acrylonitrile-butadiene-styrene (ABS)-based composites after bentonite inclusions. Melt mixing is the most preferred production method in industrial scale and basically it has very near processing parameters compared to 3D printing applications. Rheological parameters of ABS and its composites are important for 3D applications. Melt flow behavior of ABS effects the fabrication of 3D printed product at desired levels. Shear thinning and non-Newtonian viscosity characteristics of ABS make viscosity control easier and more flexible for several processing techniques including injection molding, compression molding and 3D printing.

ABS copolymer was reinforced with bentonite mineral (BNT) at four different loading ratios of 5%, 10%, 15% and 20%. ABS/BNT composites were fabricated by lab-scale micro-compounder followed by injection molding process. Mechanical, thermo-mechanical, thermal, melt-flow and morphological properties of composites were investigated by tensile, hardness and impact tests, dynamic mechanical analysis (DMA), thermo-gravimetric analysis (TGA), melt flow index (MFI) test and scanning electron microscopy (SEM), respectively.

Mechanical tests revealed that tensile strength, elongation and hardness of ABS were enhanced as BNT content increased. Glass transition temperature and storage modulus of ABS exhibited increasing trend with the additions of BNT. However, impact strength values dropped down with BNT inclusion. According to MFI test measurements, BNT incorporation displayed no significant change for MFI value of ABS. Homogeneous dispersion of BNT particles into ABS phase was deduced from SEM micrographs of composites. Loading ratio of 15% BNT was remarked as the most suitable candidate among fabricated ABS-based composites according to findings.

The advanced mechanical properties and easy processing characteristics are the reasons for usage of ABS as an engineering plastic. Owing to the increase in its usage for 3D printing technology, the ABS became popular in recent years. The utilization of ABS in this technology is in filament form with various colors and dimensions. This is because of its proper rheological features.

Melt-mixing technique was used as preparation of composites, as this processing method is widely applied in industry. This method is also providing similar processing methodology with 3D printing technology.

According to the literature survey, to the best of the authors’ knowledge, this study is the first research work regarding the melt-flow performance of ABS-based composites to evaluate their 3D printing applications and processability. ABS and BNT containing composites were characterized by tensile, impact and shore hardness tests, DMA, TGA), MFI test and SEM techniques.

This paper aims to define the effect of specimen mesostructure on the monotonic tensile behavior and tensile-fatigue life of layered acrylonitrile butadiene styrene (ABS) components fabricated by fused deposition modeling (FDM).

Tensile tests were performed on FDM dogbone specimens with four different raster orientations according to ASTM standard D638-03. Resulting ultimate tensile stresses (UTS) for each raster orientation were used to compute the maximum stress for fatigue testing, i.e. 90, 75, 60 and 50 or 45 per cent nominal values of the UTS. Multiple specimens were subjected to tension – tension fatigue cycling with stress ratio of R = 0.10 in accordance with ASTM standard D7791-12.

Both tensile strength and fatigue performance exhibited anisotropic behavior. The longitudinal (0°) and default (+45/−45°) raster orientations performed significantly better than the diagonal (45°) or transverse (90°) orientations in regards to fatigue life, as displayed in the resulting Wohler curves.

Raster orientation has a significant effect on the fatigue performance of FDM ABS components. Aligning FDM fibers along the axis of the applied stress provides improved fatigue life. If the direction of applied stresses is not expected to be constant in given application, the default raster orientation is recommended.

This project provides knowledge to the limited work published on the fatigue performance of FDM ABS components. It provides S-N fatigue life results that can serve as a foundation for future work, combining experimental investigations with theoretical principles and the statistical analysis of data.

This paper aims to focus on the development of the three-dimensional (3D) printing filaments based on acrylonitrile butadiene styrene (ABS) copolymer and styrene-ethylene/butylene-styrene (SEBS) block copolymer, with tailored viscoelastic properties and controlled flow during the 3D printing process.

In this investigation, ABS was blended with various amounts of SEBS via a melt mixing process. Then the ABS/SEBS filaments were prepared by a single-screw extruder and printed by the FDM method. The rheological properties were determined using an MCR 501 from Anton-Paar. The melt flow behavior of ABS/SEBS filaments was determined. The morphology of the filaments was studied by scanning electron microscope and the mechanical (tensile and impact) properties, surface roughness and void content of printed samples were investigated.

The rheological results can accurately interpret what drives the morphology and mechanical properties’ changes in the blends. The impact strength, toughness, elongation-at-break and anisotropy in mechanical properties of ABS samples were improved concurrently by adding 40 Wt.% of SEBS. The optimal tensile properties of blend containing 40 Wt.% SEBS samples were obtained at −45°/+45° raster angle, 0.05 mm layer thickness and XYZ build orientation. Optimized samples showed an 890% increase in elongation compared to neat ABS. Also, the impact strength of ABS samples showed a 60% improvement by adding 40 Wt.% SEBS.

The paper simultaneously evaluates the effects of material composition and 3D printing parameters (layer thickness, raster angle and build orientation) on the rheology, morphology, mechanical properties and surface roughness. Also, a mechanical properties comparison between printed samples and their compression-molded counterpart was conducted.

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

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

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

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

This study aims is to investigate the correlation between tribological and mechanical properties of the fused filament fabrication 3D-printed acrylonitrile butadiene styrene (ABS) pin with different internal geometries.

The tribological properties were determined by a dry sliding test with constant test parameters, while the hardness and modulus of elasticity were determined by microhardness and compression tests.

Although the internal geometry of the pin sample slightly affects the coefficient of friction (COF) and the wear rate of the 3D-printed ABS, it was important to design a lightweight tribo-component by reducing the material used to save energy without compromising the strength of the component. The COF and wear rate values are relatively dependent on the elastic modulus. A 3D-printed ABS pin with an internal triangular flip structure was found to have the shortest run-in period and the lowest COF with high wear resistance. Abrasive wear and delamination are the predominant wear mechanisms involved.

The findings are the subject of future research under various sliding conditions by investigating the synergistic effect of sliding speeds and applied loads to validate the results of this study.

The internal structure affects the mechanical properties and release stress concentration at the contact point, resulting in hypothetically low friction and wear. This approach may also reduce the weight of the parts without scarifying or at least preserving their preceding tribological performance. Therefore, based on our knowledge, limited studies have been conducted for the application of 3D printing in tribology, and most studies focused on improving their mechanical properties rather than correlating them with tribological properties that would benefit longer product lifespans.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0143/