scholarly journals 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 ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 4233
Author(s):  
Mulat Alubel Abtew ◽  
Francois Boussu ◽  
Pascal Bruniaux ◽  
Han Liu

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.

2020 ◽  
Vol 10 (14) ◽  
pp. 4873 ◽  
Author(s):  
Mulat Alubel Abtew ◽  
Francois Boussu ◽  
Pascal Bruniaux ◽  
Carmen Loghin ◽  
Irina Cristian

This paper investigates the effects of warp yarns ratios on the ballistic performances of three-dimensional (3D) warp interlock p-aramid fabrics. Four 3D warp interlock variants with different binding and stuffer warp yarns ratios were designed and developed. Except for warp yarns ratios, similar fabric parameters and manufacturing conditions were considered. Two-dimensional (2D) woven fabric having similar material characteristics and recommended for female seamless soft body armor are also considered for comparisons. Five ballistic panels, one from 2D plain weave fabric and the rest four from the other 3D warp interlock variants were prepared in a non-angled layer alignment and non-stitched but bust-shaped molded form. The ballistic test is carried out according to NIJ (National Institute of Justice) standard-level IIIA. Back Face Signature (BFS) was then modeled and measured to compute both trauma and panels’ energy-absorbing capability. The result showed significant ballistic improvement in the 3D warp interlock variant with optimum warp yarns ratios over traditional 2D plain weave fabrics. 3D warp interlock fabric panel made with 66.6% binding and 33.3% stuffer warp yarn ratio revealed both lower BFS depth and higher energy absorbing capacity (%) than other panels made of 2D plain weave and 3D warp interlock fabric variants.


2018 ◽  
Vol 85 (4) ◽  
Author(s):  
Dani Liu ◽  
Bahareh Shakibajahromi ◽  
Genevieve Dion ◽  
David Breen ◽  
Antonios Kontsos

The mechanical behavior of knitted textiles is simulated using finite element analysis (FEA). Given the strong coupling between geometrical and physical aspects that affect the behavior of this type of engineering materials, there are several challenges associated with the development of computational tools capable of enabling physics-based predictions, while keeping the associated computational cost appropriate for use within design optimization processes. In this context, this paper investigates the relative contribution of a number of computational factors to both local and global mechanical behavior of knitted textiles. Specifically, different yarn-to-yarn interaction definitions in three-dimensional (3D) finite element models are compared to explore their relative influence on kinematic features of knitted textiles' mechanical behavior. The relative motion between yarns identified by direct numerical simulations (DNS) is then used to construct reduced order models (ROMs), which are shown to be computationally more efficient and providing comparable predictions of the mechanical performance of knitted textiles that include interfacial effects between yarns.


2020 ◽  
pp. 152808372093728 ◽  
Author(s):  
Mulat Alubel Abtew ◽  
François Boussu ◽  
Pascal Bruniaux ◽  
Carmen Loghin ◽  
Irina Cristian ◽  
...  

Three dimensional (3D) warp interlock fabric becomes a promising structure due to its good mechanical performances. However, its complex manufacturing process can cause severe yarn damage and affects its overall final performances. The current study addressed the effects weaving process and warp yarn ratios on the multi-filaments yarn degradations and its mechanical performances while 3D warp interlock fabric manufacturing. Four different 3D warp interlock variants having similar fabric architecture, and yarn densities but different warp yarns interchange ratios were manufactured using 930dTex high-performance multi-filament (Twaron® f1000). The multi-filaments yarns at different weaving processes were tested for their tensile properties. The results show that the average tensile strength of twisted yarns show a decrement of 5.68% as compared to the bobbin yarns. Meanwhile, warping process also showed a 16.11% maximum breaking load reduction as compared to the bobbin yarn. Besides, the tensile strength of binding yarn after weaving process for samples 3D-8/0, 3D-8/4, and 3D-8/8 was reduced by 12.79%, 5.22%, and 14.22% respectively as compared to the yarn after warping process. In conclusion, yarn degradation inside the 3D woven structure was affected not only by the various process parameters but also by the type of fabric architecture made with different warp yarn ratios. These phenomena ultimately bring a great influence both on the yarn and overall mechanical performance of the final products. For this, further studies are planned to investigate the multi-filaments yarn degradation effect on the ballistic performances fibrous material as it is directly linked to the yarn performance.


2020 ◽  
Vol 4 (4) ◽  
pp. 145
Author(s):  
Mulat Alubel Abtew ◽  
Francois Boussu ◽  
Pascal Bruniaux ◽  
Carmen Loghin ◽  
Irina Cristian

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.


Author(s):  
Waleed Ahmed ◽  
Sidra Ahmed ◽  
Fady Alnajjar ◽  
Essam Zaneldin

This paper aims to investigate experimentally and using finite element analysis the performance of using three-dimensional printing technology to produce a composite sandwich panel that is made of the high-flexible core as well as with high stiffness upper and lower surfaces made of a glass fiber reinforced composite filament. There are many advantages of using sandwich structures in many applications, especially the aerospace field, where the high stiffness to strength and the lightweight is the most preferred in such applications. The conventional manufacturing methods that are used to produce sandwich panels are limited to particular core geometry, whereas manufacturing a composite core is not possible by these traditional production methods. So by using additive manufacturing technology, it becomes more applicable to design a combination of different geometries and materials to achieve properties that have never been made before, especially combining flexibility and high energy absorption keeping high strength to failure. A central deflection to a length of 0.26 is observed within the elastic zone, a remarkable ratio in beams that reflects the three-dimensional printed sandwich beams’ capability with a highly flexible core to absorb energy that would open doors for many industrial applications that is attributed to the lowest flexural rigidity (167E-3Pa · m4) of the sandwich by using the TriHex infill pattern. In contrast, the Gyroid infill structure could afford the highest central load (0.264 kN). At the peak load applied on the sandwich beam, a maximum error of 5.4% is estimated by finite element analysis lower than the experimental values.


Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 691
Author(s):  
Francisco-José Gallardo-Basile ◽  
Yannick Naunheim ◽  
Franz Roters ◽  
Martin Diehl

Lath martensite is a complex hierarchical compound structure that forms during rapid cooling of carbon steels from the austenitic phase. At the smallest, i.e., ‘single crystal’ scale, individual, elongated domains, form the elemental microstructural building blocks: the name-giving laths. Several laths of nearly identical crystallographic orientation are grouped together to blocks, in which–depending on the exact material characteristics–clearly distinguishable subblocks might be observed. Several blocks with the same habit plane together form a packet of which typically three to four together finally make up the former parent austenitic grain. Here, a fully parametrized approach is presented which converts an austenitic polycrystal representation into martensitic microstructures incorporating all these details. Two-dimensional (2D) and three-dimensional (3D) Representative Volume Elements (RVEs) are generated based on prior austenite microstructure reconstructed from a 2D experimental martensitic microstructure. The RVEs are used for high-resolution crystal plasticity simulations with a fast spectral method-based solver and a phenomenological constitutive description. The comparison of the results obtained from the 2D experimental microstructure and the 2D RVEs reveals a high quantitative agreement. The stress and strain distributions and their characteristics change significantly if 3D microstructures are used. Further simulations are conducted to systematically investigate the influence of microstructural parameters, such as lath aspect ratio, lath volume, subblock thickness, orientation scatter, and prior austenitic grain shape on the global and local mechanical behavior. These microstructural features happen to change the local mechanical behavior, whereas the average stress–strain response is not significantly altered. Correlations between the microstructure and the plastic behavior are established.


Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1271
Author(s):  
Andreas Koenig ◽  
Leonie Schmohl ◽  
Johannes Scheffler ◽  
Florian Fuchs ◽  
Michaela Schulz-Siegmund ◽  
...  

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.


e-Polymers ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 346-354
Author(s):  
Guoquan Qi ◽  
Hongxia Yan ◽  
Dongtao Qi ◽  
Houbu Li ◽  
Lushi Kong ◽  
...  

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.


2007 ◽  
Vol 345-346 ◽  
pp. 1469-1472
Author(s):  
Gab Chul Jang ◽  
Kyong Ho Chang ◽  
Chin Hyung Lee

During manufacturing the welded joint of steel structures, residual stress is produced and weld metal is used inevitably. And residual stress and weld metal influence on the static and dynamic mechanical behavior of steel structures. Therefore, to predict the mechanical behavior of steel pile with a welded joint during static and dynamic deformation, the research on the influence of the welded joints on the static and dynamic behavior of steel pile is clarified. In this paper, the residual stress distribution in a welded joint of steel piles was investigated by using three-dimensional welding analysis. The static and dynamic mechanical behavior of steel piles with a welded joint is investigated by three-dimensional elastic-plastic finite element analysis using a proposed dynamic hysteresis model. Numerical analyses of the steel pile with a welded joint were compared to that without a welded joint with respect to load carrying capacity and residual stress distribution. The influence of the welded joint on the mechanical behavior of steel piles during static and dynamic deformation was clarified by comparing analytical results


Sign in / Sign up

Export Citation Format

Share Document