Effect of Structural Parameters on the Deformational Behaviors of Multiply 3D Layer-by-Layer Angle-Interlock Para-Aramid Fabric for Fiber-Reinforcement Composite

Materials used in the technical application including composite reinforcements and ballistic fabrics should show not only good mechanical performance but also better deformational behaviors. Meanwhile, three dimensional (3D) warp interlock fabrics have been widely employed in such applications to substitute the two dimensional (2D) fabrics because of their enhanced through-the-thickness performance and excellent formability. The deformational behaviors of such 3D warp interlock fabrics have been also influenced by various internal and external parameters. To understand and fill this gap, the current paper investigates the effects of the warp yarn interchange ratios inside the fabric structure on the formability behaviors of dry 3D warp interlock p-aramid fabrics. Four 3D warp interlock architecture types made with different binding and stuffer warp yarn interchange ratios were designed and manufactured. An adapted hydraulic-driven stamping bench along with hemispherical punch was utilized for better forming behavior analysis such as in-plane shear angle and its recovery, material drawing-in and its recovery, deformational depth recovery, and required stamping forces. Based on the investigation of various formability behaviors, the formability of (3D) warp interlock fabrics were greatly influenced by the binding and stuffer warp yarns interchange ratio inside the 3D warp interlock structure. For example, preform 3D-8W-0S exhibited a maximum deformational height recovery percentage of 5.1%, whereas 3D-4W-8S recorded only 0.72%. Preform 3D-8W-4S and 3D-8W-8S revealed 1.45% and 4.35% recovery percentages toward the deformational height at maximum position. Besides, sample 3D-4S-8W revealed the maximum drawing-in recovery percentage of 43.13% and 46.98% in the machine and cross direction, respectively, around the preform peripheral edges. On the contrary, samples with higher binding warp yarns as 3D-8W-0S show the maximum drawing-in recovery percentages values of 31.21% and 34.99% in the machine and cross directions respectively.

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Additive manufacturing of polymer-based structures by extrusion technologies

Oxford Open Materials Science ◽

10.1093/oxfmat/itaa004 ◽

2020 ◽

Vol 1 (1) ◽

Author(s):

Alianna Maguire ◽

Neethu Pottackal ◽

M A S R Saadi ◽

Muhammad M Rahman ◽

Pulickel M Ajayan

Keyword(s):

Additive Manufacturing ◽

Composite Materials ◽

High Performance ◽

Mechanical Performance ◽

Three Dimensional ◽

Future Research ◽

Layer By Layer ◽

Structural Applications ◽

Materials Used ◽

Extrusion Printing

Abstract Extrusion-based additive manufacturing (AM) enables the fabrication of three-dimensional structures with intricate cellular architectures where the material is selectively dispensed through a nozzle or orifice in a layer-by-layer fashion at the macro-, meso-, and micro-scale. Polymers and their composites are one of the most widely used materials and are of great interest in the field of AM due to their vast potential for various applications, especially for the medical, military, aerospace, and automotive industries. Because architected polymer-based structures impart remarkably improved material properties such as low density and high mechanical performance compared to their bulk counterparts, this review focuses particularly on the development of such objects by extrusion-based AM intended for structural applications. This review introduces the extrusion-based AM techniques followed by a discussion on the wide variety of materials used for extrusion printing, various architected structures, and their mechanical properties. Notable advances in newly developed polymer and composite materials and their potential applications are summarized. Finally, perspectives and insights into future research of extrusion-based AM on developing high-performance ultra-light materials using polymers and their composite materials are discussed.

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Fabrication and Mechanical Characterization of Dry Three-Dimensional Warp Interlock Para-Aramid Woven Fabrics: Experimental Methods toward Applications in Composite Reinforcement and Soft Body Armor

Materials ◽

10.3390/ma13194233 ◽

2020 ◽

Vol 13 (19) ◽

pp. 4233

Author(s):

Mulat Alubel Abtew ◽

Francois Boussu ◽

Pascal Bruniaux ◽

Han Liu

Keyword(s):

Mechanical Behavior ◽

Mechanical Performance ◽

Flexural Rigidity ◽

Structural Characteristics ◽

Three Dimensional ◽

Woven Fabrics ◽

Body Armor ◽

Warp Yarn ◽

3D Warp Interlock Fabric ◽

Composite Reinforcement

Recently, three-dimensional (3D) warp interlock fabric has been involved in composite reinforcement and soft ballistic material due to its great moldability, improved impact energy-absorbing capacity, and good intra-ply resistance to delamination behaviors. However, understanding the effects of different parameters of the fabric on its mechanical behavior is necessary before the final application. The fabric architecture and its internal yarn composition are among the common influencing parameters. The current research aims to explore the effects of the warp yarn interchange ratio in the 3D warp interlock para-aramid architecture on its mechanical behavior. Thus, four 3D warp interlock variants with different warp (binding and stuffer) yarn ratios but similar architecture and structural characteristics were engineered and manufactured. Tensile and flexural rigidity mechanical tests were carried out at macro- and meso-scale according to standard EN ISO 13 934-1 and nonwoven bending length (WSP 90.5(05)), respectively. Based on the results, the warp yarn interchange ratio in the structure revealed strong influences on the tensile properties of the fabric at both the yarn and final fabric stages. Moreover, the bending stiffness of the different structures showed significant variation in both the warp and weft directions. Thus, the interchange rations of stuffer and binding warp yarn inside the 3D warp interlock fabric were found to be very key in optimizing the mechanical performance of the fabric for final applications.

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Additive manufacturing of hydroxyapatite and its composite materials: A review

Journal of Micromechanics and Molecular Physics ◽

10.1142/s2424913020300029 ◽

2020 ◽

Vol 05 (03) ◽

pp. 2030002

Author(s):

Chunze Yan ◽

Gao Ma ◽

Annan Chen ◽

Ying Chen ◽

Jiamin Wu ◽

...

Keyword(s):

Tissue Engineering ◽

Additive Manufacturing ◽

Composite Materials ◽

Computer Aided Design ◽

Mechanical Performance ◽

Three Dimensional ◽

Research Field ◽

Manufacturing Processes ◽

Layer By Layer ◽

Tissue Engineering Scaffolds

Hydroxyapatite (HA) is a promising biomaterial for tissue engineering scaffolds due to its similar performance and composition to natural bone. However, the brittleness and poor toughness of pure HA limit its clinical application. Therefore, a lot of HA composites have been prepared to improve their mechanical performance. Fabricating complex and customized tissue engineering HA scaffolds have a very high requirement for manufacturing processes. It is difficult to fabricate ideal HA porous structures for artificial bone implants using traditional manufacturing processes, such as plasma spraying–sintering, and injection forming. Additive manufacturing (AM) could make three-dimensional physical parts with complex structures directly from computer-aided-design (CAD) models in a layer-by-layer way, and therefore show unique advantages in fabricating bone tissue engineering scaffolds with complex external shape and internal microporous structures. This paper reviews the state of the art for the preparation and AM process of HA and its composite materials, and raises the prospects for this research field.

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HYDROXYAPATITE, ALGINATE, AND CHITOSAN FOR BONE SCAFFOLDS: SPECTROSCOPY STUDY

Dentika Dental Journal ◽

10.32734/dentika.v19i2.457 ◽

2016 ◽

Vol 19 (2) ◽

pp. 93-100

Author(s):

Lalita El Milla

Keyword(s):

Tissue Engineering ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Functional Groups ◽

Bone Growth ◽

Three Dimensional ◽

Dimensional Structure ◽

Tissue Engineering Scaffolds ◽

Hydroxyapatite Powder ◽

Materials Used

Scaffolds is three dimensional structure that serves as a framework for bone growth. Natural materials are often used in synthesis of bone tissue engineering scaffolds with respect to compliance with the content of the human body. Among the materials used to make scafffold was hydroxyapatite, alginate and chitosan. Hydroxyapatite powder obtained by mixing phosphoric acid and calcium hydroxide, alginate powders extracted from brown algae and chitosan powder acetylated from crab. The purpose of this study was to examine the functional groups of hydroxyapatite, alginate and chitosan. The method used in this study was laboratory experimental using Fourier Transform Infrared (FTIR) spectroscopy for hydroxyapatite, alginate and chitosan powders. The results indicated the presence of functional groups PO43-, O-H and CO32- in hydroxyapatite. In alginate there were O-H, C=O, COOH and C-O-C functional groups, whereas in chitosan there were O-H, N-H, C=O, C-N, and C-O-C. It was concluded that the third material containing functional groups as found in humans that correspond to the scaffolds material in bone tissue engineering.

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Is Micro X-ray Computer Tomography a Suitable Non-Destructive Method for the Characterisation of Dental Materials?

Polymers ◽

10.3390/polym13081271 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1271

Author(s):

Andreas Koenig ◽

Leonie Schmohl ◽

Johannes Scheffler ◽

Florian Fuchs ◽

Michaela Schulz-Siegmund ◽

...

Keyword(s):

Flexural Strength ◽

Computer Tomography ◽

Mechanical Performance ◽

Dental Materials ◽

Three Dimensional ◽

X Rays ◽

Scanning Calorimetry ◽

X Ray ◽

Multiple Measurements ◽

High Doses

The aim of the study was to investigate the effect of X-rays used in micro X-ray computer tomography (µXCT) on the mechanical performance and microstructure of a variety of dental materials. Standardised bending beams (2 × 2 × 25 mm3) were forwarded to irradiation with an industrial tomograph. Using three-dimensional datasets, the porosity of the materials was quantified and flexural strength was investigated prior to and after irradiation. The thermal properties of irradiated and unirradiated materials were analysed and compared by means of differential scanning calorimetry (DSC). Single µXCT measurements led to a significant decrease in flexural strength of polycarbonate with acrylnitril-butadien-styrol (PC-ABS). No significant influence in flexural strength was identified for resin-based composites (RBCs), poly(methyl methacrylate) (PMMA), and zinc phosphate cement (HAR) after a single irradiation by measurement. However, DSC results suggest that changes in the microstructure of PMMA are possible with increasing radiation doses (multiple measurements, longer measurements, higher output power from the X-ray tube). In summary, it must be assumed that X-ray radiation during µXCT measurement at high doses can lead to changes in the structure and properties of certain polymers.

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3D Printing of High Viscosity Reinforced Silicone Elastomers

Polymers ◽

10.3390/polym13142239 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2239

Author(s):

Nicholas Rodriguez ◽

Samantha Ruelas ◽

Jean-Baptiste Forien ◽

Nikola Dudukovic ◽

Josh DeOtte ◽

...

Keyword(s):

Mechanical Properties ◽

High Performance ◽

New Technologies ◽

Three Dimensional ◽

High Viscosity ◽

Layer By Layer ◽

Silicone Elastomers ◽

Uv Curable ◽

Octet Truss ◽

Tunable Mechanical Properties

Recent advances in additive manufacturing, specifically direct ink writing (DIW) and ink-jetting, have enabled the production of elastomeric silicone parts with deterministic control over the structure, shape, and mechanical properties. These new technologies offer rapid prototyping advantages and find applications in various fields, including biomedical devices, prosthetics, metamaterials, and soft robotics. Stereolithography (SLA) is a complementary approach with the ability to print with finer features and potentially higher throughput. However, all high-performance silicone elastomers are composites of polysiloxane networks reinforced with particulate filler, and consequently, silicone resins tend to have high viscosities (gel- or paste-like), which complicates or completely inhibits the layer-by-layer recoating process central to most SLA technologies. Herein, the design and build of a digital light projection SLA printer suitable for handling high-viscosity resins is demonstrated. Further, a series of UV-curable silicone resins with thiol-ene crosslinking and reinforced by a combination of fumed silica and MQ resins are also described. The resulting silicone elastomers are shown to have tunable mechanical properties, with 100–350% elongation and ultimate tensile strength from 1 to 2.5 MPa. Three-dimensional printed features of 0.4 mm were achieved, and complexity is demonstrated by octet-truss lattices that display negative stiffness.

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Investigations of polyethylene of raised temperature resistance service performance using autoclave test under sour medium conditions

e-Polymers ◽

10.1515/epoly-2021-0029 ◽

2021 ◽

Vol 21 (1) ◽

pp. 346-354

Author(s):

Guoquan Qi ◽

Hongxia Yan ◽

Dongtao Qi ◽

Houbu Li ◽

Lushi Kong ◽

...

Keyword(s):

Oil And Gas ◽

Mechanical Performance ◽

Three Dimensional ◽

Service Performance ◽

Degree Of Branching ◽

Temperature Resistance ◽

Temperature Conditions ◽

Dimensional Network ◽

Gas Medium ◽

Better Than

Abstract The chapter deals with the performance evaluation of the polyethylene of raised temperature resistance (PE-RT) and polyethylene (PE) using autoclave test under sour oil and gas medium conditions. The analyses of performance changes showed that PE-RT has good media resistance at 60°C. As the temperature increases, its mechanical properties decrease, accompanied by an increase in weight. Comparative analyses showed that no matter what temperature conditions are, PE-RT media resistance is better than PE80. The better media resistance of PE-RT depends on its higher degree of branching. Short branches are distributed between the crystals to form a connection between the crystals, thereby improving its heat resistance and stress under high-temperature conditions. PE-RT forms an excellent three-dimensional network structure through copolymerization, ensuring that it has better media resistance than PE80. However, the mechanical performance will be attenuated due to the high service temperature.

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Brain capillary structures of schizophrenia cases and controls show a correlation with their neuron structures

Scientific Reports ◽

10.1038/s41598-021-91233-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Rino Saiga ◽

Masayuki Uesugi ◽

Akihisa Takeuchi ◽

Kentaro Uesugi ◽

Yoshio Suzuki ◽

...

Keyword(s):

Blood Vessels ◽

Structural Parameters ◽

Three Dimensional ◽

Superior Temporal Gyrus ◽

Anterior Cingulate ◽

Dimensional Structure ◽

Constant Diameter ◽

The Mean ◽

Cartesian Coordinate ◽

Micrometer Scale

AbstractBrain blood vessels constitute a micrometer-scale vascular network responsible for supply of oxygen and nutrition. In this study, we analyzed cerebral tissues of the anterior cingulate cortex and superior temporal gyrus of schizophrenia cases and age/gender-matched controls by using synchrotron radiation microtomography or micro-CT in order to examine the three-dimensional structure of cerebral vessels. Over 1 m of cerebral blood vessels was traced to build Cartesian-coordinate models, which were then used for calculating structural parameters including the diameter and curvature of the vessels. The distribution of vessel outer diameters showed a peak at 7–9 μm, corresponding to the diameter of the capillaries. Mean curvatures of the capillary vessels showed a significant correlation to the mean curvatures of neurites, while the mean capillary diameter was almost constant, independent of the cases. Our previous studies indicated that the neurites of schizophrenia cases are thin and tortuous compared to controls. The curved capillaries with a constant diameter should occupy a nearly constant volume, while neurons suffering from neurite thinning should have reduced volumes, resulting in a volumetric imbalance between the neurons and the vessels. We suggest that the observed structural correlation between neurons and blood vessels is related to neurovascular abnormalities in schizophrenia.

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Coupled Fluid–Solid Numerical Simulation for Flow Field Characteristics and Supporting Performance of Flexible Support Cylindrical Gas Film Seal

Aerospace ◽

10.3390/aerospace8040097 ◽

2021 ◽

Vol 8 (4) ◽

pp. 97

Author(s):

Junfeng Sun ◽

Meihong Liu ◽

Zhen Xu ◽

Taohong Liao ◽

Xiangping Hu ◽

...

Keyword(s):

Flow Field ◽

Film Thickness ◽

Fluid Dynamic ◽

Structural Characteristics ◽

Structural Parameters ◽

Equivalent Stress ◽

Three Dimensional ◽

High Rotational Speed ◽

Flexible Support ◽

Flow Field Characteristics

A new type of cylindrical gas film seal (CGFS) with a flexible support is proposed according to the working characteristics of the fluid dynamic seal in high-rotational-speed fluid machinery, such as aero-engines and centrifuges. Compared with the CGFS without a flexible support, the CGFS with flexible support presents stronger radial floating characteristics since it absorbs vibration and reduces thermal deformation of the rotor system. Combined with the structural characteristics of a film seal, an analytical model of CGFS with a flexible wave foil is established. Based on the fluid-structure coupling analysis method, the three-dimensional flow field of a straight-groove CGFS model is simulated to study the effects of operating and structural parameters on the steady-state characteristics and the effects of gas film thickness, eccentricity, and the number of wave foils on the equivalent stress of the flexible support. Simulation results show that the film stiffness increases significantly when the depth of groove increases. When the gas film thickness increases, the average equivalent stress of the flexible support first decreases and then stabilizes. Furthermore, the number of wave foils affects the average foils thickness. Therefore, when selecting the number of wave foils, the support stiffness and buffer capacity should be considered simultaneously.

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A guideline for 3D printing terminology in biomedical research utilizing ISO/ASTM standards

3D Printing in Medicine ◽

10.1186/s41205-021-00098-5 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Amy E. Alexander ◽

Nicole Wake ◽

Leonid Chepelev ◽

Philipp Brantner ◽

Justin Ryan ◽

...

Keyword(s):

3D Printing ◽

Medical Literature ◽

Three Dimensional ◽

Physical Object ◽

Medical Community ◽

Layer By Layer ◽

Digital File ◽

Standardized Terminology ◽

Standard Terms ◽

The Impact

AbstractFirst patented in 1986, three-dimensional (3D) printing, also known as additive manufacturing or rapid prototyping, now encompasses a variety of distinct technology types where material is deposited, joined, or solidified layer by layer to create a physical object from a digital file. As 3D printing technologies continue to evolve, and as more manuscripts describing these technologies are published in the medical literature, it is imperative that standardized terminology for 3D printing is utilized. The purpose of this manuscript is to provide recommendations for standardized lexicons for 3D printing technologies described in the medical literature. For all 3D printing methods, standard general ISO/ASTM terms for 3D printing should be utilized. Additional, non-standard terms should be included to facilitate communication and reproducibility when the ISO/ASTM terms are insufficient in describing expository details. By aligning to these guidelines, the use of uniform terms for 3D printing and the associated technologies will lead to improved clarity and reproducibility of published work which will ultimately increase the impact of publications, facilitate quality improvement, and promote the dissemination and adoption of 3D printing in the medical community.

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