scholarly journals Load Distribution on PET-G 3D Prints of Honeycomb Cellular Structures under Compression Load

Polymers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1983
Author(s):  
Olimpia Basurto-Vázquez ◽  
Elvia P. Sánchez-Rodríguez ◽  
Graham J. McShane ◽  
Dora I. Medina
Keyword(s):  
Fused Deposition Modeling ◽  
Structural Characteristics ◽  
Honeycomb Structure ◽  
Cellular Structures ◽  
Displacement Curve ◽  
Compression Tests ◽  
Compression Load ◽  
Fused Deposition ◽  
3D Printed ◽  
Printing Direction

Energy resulting from an impact is manifested through unwanted damage to objects or persons. New materials made of cellular structures have enhanced energy absorption (EA) capabilities. The hexagonal honeycomb is widely known for its space-filling capacity, structural stability, and high EA potential. Additive manufacturing (AM) technologies have been effectively useful in a vast range of applications. The evolution of these technologies has been studied continuously, with a focus on improving the mechanical and structural characteristics of three-dimensional (3D)-printed models to create complex quality parts that satisfy design and mechanical requirements. In this study, 3D honeycomb structures of novel material polyethylene terephthalate glycol (PET-G) were fabricated by the fused deposition modeling (FDM) method with different infill density values (30%, 70%, and 100%) and printing orientations (edge, flat, and upright). The effectiveness for EA of the design and the effect of the process parameters of infill density and layer printing orientation were investigated by performing in-plane compression tests, and the set of parameters that produced superior results for better EA was determined by analyzing the area under the curve and the welding between the filament layers in the printed object via FDM. The results showed that the printing parameters implemented in this study considerably affected the mechanical properties of the 3D-printed PET-G honeycomb structure. The structure with the upright printing direction and 100% infill density exhibited an extension to delamination and fragmentation, thus, a desirable performance with a long plateau region in the load–displacement curve and major absorption of energy.

An experimental investigation on mechanical performances of 3D printed lightweight ABS pipes with different cellular wall thickness

2021 ◽  
Vol 15 (2) ◽  
pp. 8169-8177
Author(s):  
Berkay Ergene ◽  
İsmet ŞEKEROĞLU ◽  
Çağın Bolat ◽  
Bekir Yalçın
Keyword(s):  
Compressive Strength ◽  
Energy Absorption ◽  
Wall Thickness ◽  
Lattice Structure ◽  
Honeycomb Structure ◽  
Cellular Structures ◽  
Compression Tests ◽  
Absorbed Energy ◽  
Great Opportunity ◽  
3D Printed

In recent years, cellular structures have attracted great deal of attention of many researchers due to their unique properties like exhibiting high strength at low density and great energy absorption. Also, the applications of cellular structures (or lattice structures) such as wing airfoil, tire, fiber and implant, are mainly used in aerospace, automotive, textile and biomedical industries respectively. In this investigation, the idea of using cellular structures in pipes made of acrylonitrile butadiene styrene (ABS) material was focused on and four different pipe types were designed as honeycomb structure model, straight rib pattern model, hybrid version of the first two models and fully solid model. Subsequently, these models were 3D printed by using FDM method and these lightweight pipes were subjected to compression tests in order to obtain stress-strain curves of these structures. Mechanical properties of lightweight pipes like elasticity modulus, specific modulus, compressive strength, specific compressive strength, absorbed energy and specific absorbed energy were calculated and compared to each other. Moreover, deformation modes were recorded during all compression tests and reported as well. The results showed that pipe models including lattice wall thickness could be preferred for the applications which don’t require too high compressive strength and their specific energy absorption values were notably capable to compete with fully solid pipe structures. In particular, rib shape lattice structure had the highest elongation while the fully solid one possessed worst ductility. Lastly, it is pointed out that 3D printing method provides a great opportunity to have a foresight about production of uncommon parts by prototyping.

scholarly journals The Impact of Defects on Tensile Strength and Modulus of 3D Printed Parts Manufactured by Fused deposition Modeling

2021 ◽  
Author(s):  
Mobina Movahedi
Keyword(s):  
Tensile Strength ◽  
3D Printing ◽  
Fused Deposition Modeling ◽  
Research Work ◽  
Layer By Layer ◽  
Fused Deposition ◽  
Deposition Modeling ◽  
3D Printed ◽  
The Impact ◽  
Printing Direction

Additive manufacturing (AM), 3D printing, is defined as a process of depositing materials layer by layer to create three-dimensional printed models, as opposed to subtractive manufacturing methodologies. It has the potential of revolutionizing field of manufacturing, which allows us to create more complex geometries with lower cost and faster speed in comparison to injection molding, compression forming, and forging. Therefore, 3D printing can shorten the design manufacturing cycle, reduce the production cost, and increase the competitiveness. Due to the improvements of processes and advancements of modeling and design, Fused Deposition Modeling (FDM) technologies, a common 3D printing technique, have been involved in wide various applications in the past three decades and numerous studies have been gathered. This research work studies directional properties of FDM 3D printed thermoplastic parts per ASTM D638. Tensile strength and modulus of the coupons along and perpendicular to the printing direction are evaluated. It is observed that FDM 3D printing introduces anisotropic behavior to the manufactured part, e.g. tensile strength of 57.7 and 30.8 MPa for loading along and perpendicular to the printing direction, respectively. FDM 3D printers are not ideal and introduce defects into the manufactured parts, e.g. in the form of missing material, gap. This study investigates the impact of gaps on tensile strength and modulus of 3D printed parts. A maximum reduction of 20% in strength is found for a gap (missing bead) along the loading direction.

scholarly journals The Impact of Defects on Tensile Strength and Modulus of 3D Printed Parts Manufactured by Fused deposition Modeling

2021 ◽  
Author(s):  
Mobina Movahedi
Keyword(s):  
Tensile Strength ◽  
3D Printing ◽  
Fused Deposition Modeling ◽  
Research Work ◽  
Layer By Layer ◽  
Fused Deposition ◽  
Deposition Modeling ◽  
3D Printed ◽  
The Impact ◽  
Printing Direction

Additive manufacturing (AM), 3D printing, is defined as a process of depositing materials layer by layer to create three-dimensional printed models, as opposed to subtractive manufacturing methodologies. It has the potential of revolutionizing field of manufacturing, which allows us to create more complex geometries with lower cost and faster speed in comparison to injection molding, compression forming, and forging. Therefore, 3D printing can shorten the design manufacturing cycle, reduce the production cost, and increase the competitiveness. Due to the improvements of processes and advancements of modeling and design, Fused Deposition Modeling (FDM) technologies, a common 3D printing technique, have been involved in wide various applications in the past three decades and numerous studies have been gathered. This research work studies directional properties of FDM 3D printed thermoplastic parts per ASTM D638. Tensile strength and modulus of the coupons along and perpendicular to the printing direction are evaluated. It is observed that FDM 3D printing introduces anisotropic behavior to the manufactured part, e.g. tensile strength of 57.7 and 30.8 MPa for loading along and perpendicular to the printing direction, respectively. FDM 3D printers are not ideal and introduce defects into the manufactured parts, e.g. in the form of missing material, gap. This study investigates the impact of gaps on tensile strength and modulus of 3D printed parts. A maximum reduction of 20% in strength is found for a gap (missing bead) along the loading direction.

scholarly journals Characterization of Electrical Heating Performance of CFDM 3D-Printed Graphene/Polylactic Acid (PLA) Horseshoe Pattern with Different 3D Printing Directions

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2955
Author(s):  
Hyelim Kim ◽  
Sunhee Lee
Keyword(s):  
3D Printing ◽  
Polylactic Acid ◽  
Cotton Fabric ◽  
Fused Deposition Modeling ◽  
Surface Resistivity ◽  
Electrical Heating ◽  
Process Technology ◽  
Fused Deposition ◽  
3D Printed ◽  
Printing Direction

This study manufactured a horseshoe pattern (HP)-type electrical heating element based on a graphene/polylactic acid (GR/PLA) filament using CFDM (conveyor-fused deposition modeling) 3D printing technology, which is a new manufacturing process technology. CFDM 3D printing HP was fabricated in the different printing directions of 0°, 45°, and 90°. To confirm the effects of different 3D printing directions, the morphology, surface resistivity, and electrical heating properties of the different HPs were analyzed. In addition, the CFDM 3D-printed HPs made using different printing directions were printed on cotton fabric to confirm their applicability as fabric heating elements, and their electrical heating properties were measured. Regarding the morphology of the GR/PLA-HP, each sample was stacked according to the printing direction. It was also confirmed through FE-SEM images that the graphene was arranged according to the printing direction in which the nozzle moved. In the XRD pattern analysis, the GR/PLA-HP samples showed two diffraction peaks of PLA and graphene. The sizes of those peaks were increased in the order of 90° < 45° ≤ 0° according to the printing direction, which also affected the electrical and electric heating properties. The surface resistivities of the GR/PLA-HP samples were shown to be increased in the order of 0° < 45° < 90°, indicating that the electrical properties of GR/PLA HP printed at 0° were improved compared to those of the other samples. When 30 V was applied to three GR/PLA-HP samples according to the printing direction, the surface temperatures were decreased in the order of 0° < 45° < 90°, and the samples were indicated as 83.6, 80.6, and 52.5 °C, respectively; the same result was shown when the samples were printed on cotton fabric. Therefore, it was confirmed that the GR/PLA CFDM 3D-printed HP sample printed at 0° direction showed low surface resistivity and high surface temperature, so that improving the electrical heating properties.

scholarly journals 3D Printing On-Water Sports Boards with Bio-Inspired Core Designs

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 250 ◽  
Author(s):  
Aref Soltani ◽  
Reza Noroozi ◽  
Mahdi Bodaghi ◽  
Ali Zolfagharian ◽  
Reza Hedayati
Keyword(s):  
3D Printing ◽  
Fused Deposition Modeling ◽  
Performance Enhancement ◽  
Close Relation ◽  
Honeycomb Structure ◽  
Functionally Graded ◽  
Core Structure ◽  
Fused Deposition ◽  
3D Printed ◽  
Water Sports

Modeling and analyzing the sports equipment for injury prevention, reduction in cost, and performance enhancement have gained considerable attention in the sports engineering community. In this regard, the structure study of on-water sports board (surfboard, kiteboard, and skimboard) is vital due to its close relation with environmental and human health as well as performance and safety of the board. The aim of this paper is to advance the on-water sports board through various bio-inspired core structure designs such as honeycomb, spiderweb, pinecone, and carbon atom configuration fabricated by three-dimensional (3D) printing technology. Fused deposition modeling was employed to fabricate complex structures from polylactic acid (PLA) materials. A 3D-printed sample board with a uniform honeycomb structure was designed, 3D printed, and tested under three-point bending conditions. A geometrically linear analytical method was developed for the honeycomb core structure using the energy method and considering the equivalent section for honeycombs. A geometrically non-linear finite element method based on the ABAQUS software was also employed to simulate the boards with various core designs. Experiments were conducted to verify the analytical and numerical results. After validation, various patterns were simulated, and it was found that bio-inspired functionally graded honeycomb structure had the best bending performance. Due to the absence of similar designs and results in the literature, this paper is expected to advance the state of the art of on-water sports boards and provide designers with structures that could enhance the performance of sports equipment.

Biodegradable 3D Printed Polymer Microneedles for Transdermal Drug Delivery

2018 ◽  
Author(s):  
Michael A. Luzuriaga ◽  
Danielle R. Berry ◽  
John C. Reagan ◽  
Ronald A. Smaldone ◽  
Jeremiah J. Gassensmith
Keyword(s):  
Drug Delivery ◽  
3D Printing ◽  
Transdermal Drug Delivery ◽  
Fused Deposition Modeling ◽  
Fused Deposition ◽  
Modeling Software ◽  
Deposition Modeling ◽  
3D Printed ◽  
Microfabrication Technique ◽  
Mechanical Strengths

Biodegradable polymer microneedle (MN) arrays are an emerging class of transdermal drug delivery devices that promise a painless and sanitary alternative to syringes; however, prototyping bespoke needle architectures is expensive and requires production of new master templates. Here, we present a new microfabrication technique for MNs using fused deposition modeling (FDM) 3D printing using polylactic acid, an FDA approved, renewable, biodegradable, thermoplastic material. We show how this natural degradability can be exploited to overcome a key challenge of FDM 3D printing, in particular the low resolution of these printers. We improved the feature size of the printed parts significantly by developing a post fabrication chemical etching protocol, which allowed us to access tip sizes as small as 1 μm. With 3D modeling software, various MN shapes were designed and printed rapidly with custom needle density, length, and shape. Scanning electron microscopy confirmed that our method resulted in needle tip sizes in the range of 1 – 55 µm, which could successfully penetrate and break off into porcine skin. We have also shown that these MNs have comparable mechanical strengths to currently fabricated MNs and we further demonstrated how the swellability of PLA can be exploited to load small molecule drugs and how its degradability in skin can release those small molecules over time.

scholarly journals Quality Control in 3D Printing: Accuracy Analysis of 3D-Printed Models of Patient-Specific Anatomy

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1021
Author(s):  
Bernhard Dorweiler ◽  
Pia Elisabeth Baqué ◽  
Rayan Chaban ◽  
Ahmed Ghazy ◽  
Oroa Salem
Keyword(s):  
Wall Thickness ◽  
Large Scale ◽  
Fused Deposition Modeling ◽  
Vascular Anatomy ◽  
3D Models ◽  
Patient Specific ◽  
Stl File ◽  
Fused Deposition ◽  
3D Printed ◽  
The Mean

As comparative data on the precision of 3D-printed anatomical models are sparse, the aim of this study was to evaluate the accuracy of 3D-printed models of vascular anatomy generated by two commonly used printing technologies. Thirty-five 3D models of large (aortic, wall thickness of 2 mm, n = 30) and small (coronary, wall thickness of 1.25 mm, n = 5) vessels printed with fused deposition modeling (FDM) (rigid, n = 20) and PolyJet (flexible, n = 15) technology were subjected to high-resolution CT scans. From the resulting DICOM (Digital Imaging and Communications in Medicine) dataset, an STL file was generated and wall thickness as well as surface congruency were compared with the original STL file using dedicated 3D engineering software. The mean wall thickness for the large-scale aortic models was 2.11 µm (+5%), and 1.26 µm (+0.8%) for the coronary models, resulting in an overall mean wall thickness of +5% for all 35 3D models when compared to the original STL file. The mean surface deviation was found to be +120 µm for all models, with +100 µm for the aortic and +180 µm for the coronary 3D models, respectively. Both printing technologies were found to conform with the currently set standards of accuracy (<1 mm), demonstrating that accurate 3D models of large and small vessel anatomy can be generated by both FDM and PolyJet printing technology using rigid and flexible polymers.

scholarly journals Controlling magnetic properties of 3D-printed magnetic elastomer structures via fused deposition modeling

AIP Advances ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 025223
Author(s):  
Thomas M. Calascione ◽  
Nathan A. Fischer ◽  
Thomas J. Lee ◽  
Hannah G. Thatcher ◽  
Brittany B. Nelson-Cheeseman
Keyword(s):  
Magnetic Properties ◽  
Fused Deposition Modeling ◽  
Fused Deposition ◽  
Deposition Modeling ◽  
3D Printed

scholarly journals Pressure Orientation-Dependent Recovery of 3D-Printed PLA Objects with Varying Infill Degree

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1275 ◽  
Author(s):  
Guido Ehrmann ◽  
Andrea Ehrmann
Keyword(s):  
Shape Memory ◽  
Fused Deposition Modeling ◽  
Static Load ◽  
Shape Memory Polymer ◽  
Applied Pressure ◽  
Poly Lactic Acid ◽  
Fused Deposition ◽  
Deposition Modeling ◽  
Load Tests ◽  
3D Printed

Poly(lactic acid) is not only one of the most often used materials for 3D printing via fused deposition modeling (FDM), but also a shape-memory polymer. This means that objects printed from PLA can, to a certain extent, be deformed and regenerate their original shape automatically when they are heated to a moderate temperature of about 60–100 °C. It is important to note that pure PLA cannot restore broken bonds, so that it is necessary to find structures which can take up large forces by deformation without full breaks. Here we report on the continuation of previous tests on 3D-printed cubes with different infill patterns and degrees, now investigating the influence of the orientation of the applied pressure on the recovery properties. We find that for the applied gyroid pattern, indentation on the front parallel to the layers gives the worst recovery due to nearly full layer separation, while indentation on the front perpendicular to the layers or diagonal gives significantly better results. Pressing from the top, either diagonal or parallel to an edge, interestingly leads to a different residual strain than pressing from front, with indentation on top always firstly leading to an expansion towards the indenter after the first few quasi-static load tests. To quantitatively evaluate these results, new measures are suggested which could be adopted by other groups working on shape-memory polymers.

Sign in / Sign up

Export Citation Format

Share Document