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Heliyon May 2024Metal Extrusion (MEX) is a leading 3D printing technology for polymers, enabling intricate designs and personalized products in various applications. The current study...
Metal Extrusion (MEX) is a leading 3D printing technology for polymers, enabling intricate designs and personalized products in various applications. The current study evaluate how infill density affects the tensile, flexural, compressive, Izod impact and fracture behaviour of Acrylonitrile Butadiene Styrene (ABS) and Carbon Fiber Reinforced-Acrylonitrile Butadiene Styrene (CF-ABS) specimens manufactured using the MEX method. Different infill densities of 20, 40, 60 and 80 % are used in the production of honeycomb infill pattern samples for investigating the mechanical as well as fracture behaviour of MEX ABS/CF-ABS components. The experimental runs of fabricated composites were tested using a digital Izod impact tester and servo-controlled hydraulic universal testing machine, following ASTM standard procedures. The experimental findings show that CF-ABS specimens with an 80 % infill density and honeycomb fill pattern showed significant improvements in tensile strength, modulus, yield strength and elongation. The flexural strength (64.74 %), flexural modulus (209.15 %), compressive strength (125.21 %), compressive modulus (108.34 %) and impact strength (38.91 %) of these specimens are comparable to those of 3D printed ABS specimens and other infill densities. The research shows that precise management of processing variables can greatly improve the mechanical properties of 3D-printed ABS samples, providing valuable insights for a range of applications.
PubMed: 38707363
DOI: 10.1016/j.heliyon.2024.e29920 -
Photochemical & Photobiological... May 2024Double difunctionalization of a vinyl ether tethered hydroxy or carbamoyl group with electron-deficient alkenes such as acrylonitrile or acrylic esters was achieved by...
Double difunctionalization of a vinyl ether tethered hydroxy or carbamoyl group with electron-deficient alkenes such as acrylonitrile or acrylic esters was achieved by visible-light irradiation in a two-molecule photoredox system. Use of anhydrous acetonitrile solution as a solvent promoted both dimerization of the radical cation of electron-rich alkene with electron-rich alkene and intramolecular nucleophilic addition to generate an electron-rich radical that was added to electron-deficient alkene to furnish the double difunctionalized product. A variety of electronically differentiated rich and deficient alkenes were used in the photoreaction; a simple construction of a complex carbon framework containing acetal from simple alkenes was successful under mild conditions.
PubMed: 38703275
DOI: 10.1007/s43630-024-00588-5 -
Journal of Applied Clinical Medical... May 2024Surface-guided radiotherapy (SGRT) is adopted by several institutions; however, reports on the phantoms used to assess the precision of the SGRT setup are limited.
BACKGROUND
Surface-guided radiotherapy (SGRT) is adopted by several institutions; however, reports on the phantoms used to assess the precision of the SGRT setup are limited.
PURPOSE
The purpose of this study was to develop a phantom to verify the accuracy of the irradiation position during skin mark-less SGRT.
METHODS
An acrylonitrile butadiene styrene (ABS) plastic cube phantom with a diameter of 150 mm on each side containing a dummy target of 15 mm and two types of body surface-shaped phantoms (breast/face shape) that could be attached to the cube phantom were fabricated. Films can be inserted on four sides of the cubic phantom (left, right, anterior and posterior), and the center of radiation can be calculated by irradiating the dummy target with orthogonal MV beams. Three types of SGRT using a VOXELAN-HEV600M (Electronics Research&Development Corporation, Okayama, Japan) were evaluated using this phantom: (i) SGRT-a SGRT set-up based solely on a computed tomography (CT)-reference image. (ii) SGRT + CBCT-a method where cone beam computed tomography (CBCT) matching was performed after SGRT. (iii) SGRT-a resetup technique using a scan reference image obtained after completing the (ii) step.
RESULTS
Both the breast and face phantoms were recognized in the SGRT system without problems. SGRT ensure precision within 1 mm/1° for breast and face verification, respectively. All SGRT methods showed comparable rotational accuracies with no significant disparities.
CONCLUSIONS
The developed phantom was useful for verifying the accuracy of skin mark-less SGRT position matching. The SGRT demonstrated the feasibility of achieving skin-mark less SGRT with high accuracy, with deviations of less than 1 mm. Additional research is necessary to evaluate the suitability of the developed phantoms for use in various facilities and systems. This phantom could be used for postal surveys in the future.
PubMed: 38696715
DOI: 10.1002/acm2.14381 -
3D Printing and Additive Manufacturing Apr 2024Additive manufacturing is becoming a global phenomenon due to its versatile properties and numerous benefits, which is not possible by conventional machining processes....
Additive manufacturing is becoming a global phenomenon due to its versatile properties and numerous benefits, which is not possible by conventional machining processes. Fused deposition modeling (FDM) shows a huge potential of shift from rapid prototyping toward the rapid manufacturing. Nowadays, the strength of the FDM-printed parts is very important to consider along with all the printing parameters, which affect the strength of these parts. This study includes the investigation of printing parameters (infill density, layer thickness, and shell count) on the strength of FDM-printed parts of acrylonitrile butadiene styrene (ABS) and carbon fiber-reinforced ABS (ABS-CF). These printing parameters directly affect the quality as well as the strength of the 3D-printed parts through FDM. Tensile tests were performed on the universal testing machine on both types of printed parts. The optimized parameters for the 3D-printed samples of the pristine ABS are found to be 0.1045 mm of layer thickness, 57.72% of infill density, and 7.63 numbers of shell count, while the optimum parameters obtained for ABS-CF are 0.2780 mm of layer thickness, 28.37% of infill density, and 9.88 numbers of shell count. The results show that the layer thickness and shell count have a significant effect on the ultimate tensile strength of the 3D-printed parts.
PubMed: 38689930
DOI: 10.1089/3dp.2022.0199 -
3D Printing and Additive Manufacturing Apr 2024Additive manufacturing processes have recently been used more frequently since they offer high design freedom and easy individualization of components. The processes...
Additive manufacturing processes have recently been used more frequently since they offer high design freedom and easy individualization of components. The processes have been optimized to improve mechanical performance of the manufactured parts. Nevertheless, properties of components made by means of injection molding could not be reached yet. In the study at hand, ultrasonic phase spectroscopy (UPS) is used to compare the elastic properties of acrylonitrile butadiene styrene specimens manufactured by injection molding, by fused filament fabrication, and the Arburg plastic freeforming process. UPS allows a nondestructive and prompt determination of the elastic modulus and allows evaluation of the mechanical properties in every direction in space. In the end, results of UPS are compared with properties derived by uniaxial tensile tests to validate UPS as a test method for the determination of the mechanical properties of polymers. Regardless of the manufacturing process, an approximately linear dependence of the elastic moduli on the density can be determined. Furthermore, the quasistatic properties of the injection molded samples consistently exhibit the mechanical properties of the other samples by at least 10%.
PubMed: 38689929
DOI: 10.1089/3dp.2022.0148 -
3D Printing and Additive Manufacturing Apr 2024The growing application of additive technologies in various industrial fields determines the undertaking of research in this direction. The need to study mechanical...
The growing application of additive technologies in various industrial fields determines the undertaking of research in this direction. The need to study mechanical properties, including rheological properties, is necessitated by the use of additively manufactured models as utility models. Furthermore, the values of mechanical properties are affected by the technological parameters of 3D printing. One of the popular engineering materials used in 3D printing is acrylonitrile butadiene and styrene, commonly known by the abbreviated name ABS, which is quite hard and resistant to high temperatures. This article presents a study of the rheological properties of ABS material using multiparameter ideal body models. Two rheological phenomena of stress relaxation and creep were evaluated. The effects of two technological parameters, layer height and printing direction, on the resulting values of elastic moduli and dynamic viscosity coefficients were also evaluated. The elastic moduli and dynamic viscosity coefficients were calculated using the Maxwell-Wiechert and Kelvin-Voight models. The study showed the effect of layer height on rheological properties. Moreover, very good fit was obtained between the multiparameter rheological models and the experimental curves, which are shown by the average value of and . The presented research can be used by designers to design machine parts or car or aircraft components. Moreover, research expands knowledge of the mechanical properties of additively manufactured parts.
PubMed: 38689920
DOI: 10.1089/3dp.2022.0298 -
3D Printing and Additive Manufacturing Apr 2024Multimaterial additive manufacturing is expanding the design space realizable with 3D printing, yet is largely constrained to sequential deposition of each individual...
Multimaterial additive manufacturing is expanding the design space realizable with 3D printing, yet is largely constrained to sequential deposition of each individual material. The ability to coextrude two materials and change the ratio of materials while printing would enable custom-tailored polymer composites. Here, the evolution of a dynamic material coextrusion process for additive manufacturing capable of printing any ratio between and including two neat input materials is described across 3 hot-end generations and 14 implemented design iterations. The designs evolved with increased understanding of manufacturing constraints associated with the additive manufacturing of metal components with internal flow bore diameters on the order of 2 mm and typical bore length around 50 mm. The second generation overcame this issue by partitioning the design into two pieces to locate the flow channel geometry at the interface between the components so that the details could be easily printed on the components' external surfaces. The third concept generation then focused on minimizing flow channel volume to reduce the average length when transitioning between materials by 92%. The third-generation design was also used to investigate the improvements in dimensional stability during annealing of acrylonitrile butadiene styrene (ABS) made possible by coextruding ABS with a polycarbonate (PC) core. The standard deviation of part shrinkage after annealing was 7.08% for the neat ABS but reduced to 0.24% for the coextruded ABS/PC components.
PubMed: 38689910
DOI: 10.1089/3dp.2022.0197 -
3D Printing and Additive Manufacturing Apr 2024Fused Granular Fabrication Additive Manufacturing (FGF AM) has the capability to create tooling that is lower cost than conventionally manufactured tooling and still has...
Fused Granular Fabrication Additive Manufacturing (FGF AM) has the capability to create tooling that is lower cost than conventionally manufactured tooling and still has sufficient properties for many applications. A vacuum infusion (VI) mold was printed from fiberglass-acrylonitrile butadiene styrene (ABS) and evaluated for wear and suitability for small VI runs. The mold was designed to accentuate high wear as a "worst case" scenario. The mold was able to produce 10 parts successfully before any noticeable change occurred to the surface finish. By 14 parts, the surface finish had roughened sufficiently that demolding was difficult and resulted in damage to the part. Profilometry measurements showed a 7 × increase in roughness over the run. No significant tool wear or change in geometry was detected. Even longer life would be expected for typical tooling designs since the test mold was deliberately designed to accentuate wear and demolding issues. Based on these results, similar FGF molds are a feasible option for short run VI production for prototyping or low-volume composites manufacturing, possibly at lower cost and quicker turnaround time than machined aluminum molds.
PubMed: 38689908
DOI: 10.1089/3dp.2022.0130 -
3D Printing and Additive Manufacturing Apr 2024Fused deposition modeling (FDM) is widely used in the rapid prototyping of polymers. Polyamide (PA) has excellent mechanical properties, but its application in FDM is...
Fused deposition modeling (FDM) is widely used in the rapid prototyping of polymers. Polyamide (PA) has excellent mechanical properties, but its application in FDM is limited due to its high water absorption, warpage, and forming shrinkage. The material of the filament and the printing parameters of the printer are two critical aspects that affect the performance of a component. The prepared PA6/PA66 (composite polyamide [COPA], PA6:PA66 = 85:15) composite (COPA: acrylonitrile butadiene styrene [ABS]: maleic anhydride grafted acrylonitrile butadiene styrene [ABS-g-MAH]: polyethylene = 800:133:67:100) has low water absorption (0.39%) and high dimensional stability, which has a good application prospect in FDM. The influence of eight FDM parameters, including three rarely reported, on the properties of PA6/PA66 composite specimens was investigated by the Taguchi method. The significance of influencing factors was evaluated by analysis of variance (ANOVA) and the stability by signal-noise ratio. When the layer thickness was 0.15 mm, the infill pattern was zigzags, the build plate adhesion type was brim, and the distance from the nozzle to the printing platform and the layer thickness (ΔL) was 0.05 mm; the specimens' dimensional accuracy, surface quality, and mechanical properties were better than other levels. The layer thickness and infill pattern were the two most important factors. The switch of the cooling fan and the temperature printing platform played a significant role in the specimens' dimensional accuracy and surface quality. ΔL tremendously influenced the thickness and warping degree of the specimens. The preparation of high-performance PA composites and the investigation of multiparameters by the Taguchi method provide a possible solution for applying polyamide in FDM.
PubMed: 38689904
DOI: 10.1089/3dp.2022.0306 -
3D Printing and Additive Manufacturing Apr 2024Advances in multimaterial 3D printing are enabling the construction of advantageous engineering structures that benefit from material synergies. Cellular structures,...
Advances in multimaterial 3D printing are enabling the construction of advantageous engineering structures that benefit from material synergies. Cellular structures, such as honeycombs, provide high-energy absorption to weight ratios that could benefit from multimaterial strategies to improve the safety and performance of engineered systems. In this study, we investigate the energy absorption for honeycombs with square and hexagonal unit cells constructed from acrylonitrile butadiene styrene (ABS) and thermoplastic polyurethane (TPU). Honeycombs were fabricated and tested for out-of-plane and in-plane compression using ABS, TPU, and a combination of ABS with a central TPU band of tunable height. Out-of-plane energy absorption for square honeycombs increased from 2.2 kN·mm for TPU samples to 11.5 kN·mm for ABS samples and energy absorption of hexagonal honeycombs increased from 2.9 to 15.1 kN·mm as proportions of TPU/ABS were altered. In-plane loading demonstrated a sequential collapse of unit cell rows in square honeycombs with energy absorption of 0.1 to 2.6 kN·mm and a gradual failure of hexagonal honeycombs with energy absorption of 0.6 to 2.0 kN·mm. These results demonstrate how multimaterial combinations affect honeycomb compressive response by highlighting their benefits for controlled energy absorption and deformation for tunable performance in diverse engineering applications.
PubMed: 38689900
DOI: 10.1089/3dp.2022.0196