Woven Angle Research Articles

Novel sulfonated calixarenes derived crosslinker for reinforcing and toughening collagen: Relevance between structure and properties

AbstractCollagen is widely used in the development of new functional materials due to its high structural stability, good biocompatibility, and excellent hydrophilicity, but the collagen protein denatures easily, which makes its thermal stability and mechanical strength difficult to reach some of the parameters required in the application. To solve this, protein crosslinking is an effective way to better use collagen. In this paper, we compared the thermal stability and morphological stability of three kinds of sulfonated calixarenes crosslinked collagen before and after the treatment. The results showed that sulfonated calixarenes could significantly improve the thermal stability and morphological stability of dermal collagen. The reinforcing and toughening mechanism of the sulfonated calixarenes was revealed by scanning electron microscopy (SEM), infrared spectroscopy (FT‐IR), attenuated total reflection‐Fourier transform infrared spectroscopy (ATR‐FTIR), ultraviolet–visible–near‐infrared (UV–vis–NIR) spectrometer, X‐ray diffraction detection (XRD), atomic force microscopy (AFM), and circular dichroism (CD) detection. The results showed that sulfonated calixarenes were evenly distributed in collagen fibers and formed hydrogen bonds or electrovalent bonds with amino groups, peptide groups, or amide groups in collagen to improve the thermal stability of the collagen. Three kinds of sulfonated calixarenes enter collagen fiber to support the collagen, increase the three‐dimensional weave angle of collagen, and improve the physical and mechanical properties of collagen, thereby toughening and enhancing the collagen. Based on the above studies, the reinforcing and toughening mechanism of the sulfonated calixarenes crosslinked collagen was established. Confirmed the existence of hydrogen bonds between the three sulfonated calixarenes and collagen, and the nonchemical bond energy of the system was proportional to the molecular size of sulfonated calixarenes.

Effect of Process Parameters on Arc Behavior and Weld Formation in Weaving Gas Tungsten Arc Welding

The arc welding with weaving has been used widely to obtain better weld quality by avoiding lack of side wall fusion and improve the weld efficiency by obtaining the wide weld. But the effect of weaving process parameter on the weld is not clear. The aim of this work is to study the effect of process parameters on arc behavior and weld formation in Weaving-Gas Tungsten Arc Welding (W-GTAW), those parameters include welding current, tungsten electrode height from the electrode tip to upper surface of workpiece, weave angle, weave speed, and weave stop time on the left and right sides. The instantaneous arc shape and electrical signal data were collected by high-speed camera and electrical signal acquisition system, respectively. Furthermore, the weld morphology was also systematically analyzed. This result shows that the bottom surface radius of the arc changed with weaving in the W-GTAW. When the weave speed increased to 0.40 × 10−1 rad/s, the change of the radius was the least, with only 0.10 mm drift, and the difference between the arc forces in the middle and the two sides of the molten pool was smallest in all experiments. Compared with the welding stability of each process, decreasing the tungsten electrode height, weave angle and speed could significantly enhance the welding stability. The forming coefficient of weld with a weave angle of 1.9° was 3.11. It shows that increasing reasonably the weave angle and speed can increase the weld penetration and might help reduce stress concentration and hot crack tendency of the weld. When the welding current is reduced to 130 A for W-GTAW welding, the hardness transition from base metal (BM) zone to weld zone (WZ) is more gentle. Furthermore, the W-GTAW technology shows great application potential in weld forming control by adjusting process parameters.

Influence of weave architecture on mechanical response of SiCf-SiCm tubular composites

Due to their high resistance to radiation damage and elevated temperature, silicon carbide fiber-reinforced, silicon carbide matrix composites (SiCf-SiCm) are identified as potential cladding structures for use in nuclear reactors. In this study, four composite architectures with varying ply numbers along the thickness direction and different biaxial or triaxial plain weave orientations at either 45° or 60°, were systematically evaluated under various stress states to assess the influence of weave architecture on mechanical performance. Experiments were conducted on SiCf-SiCm composite tubes under tensile hoop, axial compression, and rotating flexural loading to evaluate the mechanical response and investigate the failure modes using high-speed imaging and digital image correlation (DIC) techniques. It was found that for tensile hoop burst and flexural loading, the braiding angle had the most significant influence on the strength of the composite, whereas the effect of fiber angle was more limited for compression testing. Under axial compression a unique failure mode where a microcrack nucleates and grows only to a length equal to the thickness of a single yarn was identified. This crack growth behavior is reflected as periodic oscillations in the load-displacement response. For both axial and hoop loading, regardless of weave angle and number of plies, failure always initiated parallel to the tube axis in a single yarn and the cumulative interaction of these microcracks lead to either axial burst or fracture at an angle to the tube axis along a yarn. These results point to the importance of customizing the design of tube architecture for enhanced performance in specified nuclear applications.

Effect of Weave Angle on The Geometrical Properties of Square Plain Fabrics of Circular and Elliptical Thread Cross Sections.(Dept.T)

Effect of Weave Angle on The Geometrical Properties of Square Plain Fabrics of Circular and Elliptical Thread Cross Sections.(Dept.T)

Influence of Tensile Stress on Woven Compression Bandage Structure and Porosity

Abstract Woven compression bandage (CB) is one of the elastic textiles that exert pressure on muscles. With a defined tensile strength, it is possible to create the required compression on the given body parts. This work aims to investigate the relationship between woven fabric deformation, porosity, and tensile stress properties of three main types of woven CBs. All bandage samples are applied on human leg using two- and three-layer bandaging techniques. Bandage porosity is calculated for all frames at different weave angles using NIS software. Woven bandage construction parameters which are given by the preparation of warp and weft yarns, twist, count, and density along with woven fabric weave, type of weaving, and finishing process are the main factors that influence the bandage properties. Several methods considering thread distributions have been developed to determine the woven fabric's porosity during the tensile stress. Experimental results confirm that bandage porosity is directly proportional to the bandage extension and weave angle that ranges from 44° to 90°. The novelty of candidate study is to introduce practical remarks to the patient for optimizing the required bandage pressure by suitable extension or applied tension or weave angle for two- and three-layer bandaging systems.

Pengaruh Woven Angle dan Proses Penekanan terhadap Tegangan Tarik pada Natural Fiber Laminate Composite

The aim of this study is to investigate the effects of pressure and woven angle on the tensile strength of natural fiber laminate composite. Pandanus tectorius and polymethyl methacrylate (PMMA) was used as natural fiber and matrix, respectively. The epoxy adhesive joint is used to connect between natural fiber and matrix. The pressure time of 10 s,15 s, 30 s and the pressure of 20 N/mm 2 , 40 N/mm 2 , 60 N/mm 2 were used in this study. In addition, the angle of the 0 o / 90 o and 45 o / 45 o woven angle is used as the initial reference for fiber orientation before pressure is applied. From the results of the study, it can be concluded that the addition of a pressure of 60 N / mm 2 and pressure time of 30 s has the highest tensile strength both at the angle of 0 o / 90 o and 45 o / 45 o . However, the tensile strength at the angle of 0 o / 90 o is higher that 45 o / 45 o . In addition, the number of adhesives decreased with increasing the pressure which will lead to delaminating.

Prediction of delamination onset and growth for AP-PLY composite laminates using the finite element method

A recently developed fibre placement architecture, Advanced Placed Ply (AP-PLY), has been shown to have promising damage tolerance characteristics for composite structures. Understanding delamination creation and growth in such architecture is of particular concern. Approaches to predict delamination onset in AP-PLY architectures and to analyse delamination growth are presented. The recovered interlaminar stresses between layers combined with a maximum stress criterion were used to determine delamination onset of simple AP-PLY composite laminates under out-of-plane loads. 2D finite element models with cohesive elements inserted at the interfaces of woven layers were used to evaluate the delamination initiation and propagation in different woven patterns of simple AP-PLY composite beams. The predictions were compared to results from the stress recovery method and to test results. The parameters of the woven pattern, such as woven angle, number of woven plies, number of straight filling plies, and the location of the woven patterns through the thickness direction, were investigated and shown to have a significant effect on delamination creation and growth.

Modeling of heterogeneous heat transfer in fabrics

Thermal comfort, an important factor when designing fabric, is strongly related to heat transfer in the fabric. Fabric is not homogeneous because the constituent yarns are interlaced at a certain weave angle, and the contact area between yarns varies. Therefore, heat transfer along the yarn in the fabric is not yet well understood. In this study, we developed a heterogeneous fabric model in which heat transfer along the longitudinal and transverse directions of the yarn is treated independently, and proposed a method for estimating the contact heat transfer coefficients for yarns. The geometrical fabric structure was constructed based on the cross section of three fabrics observed with a three-dimensional microscope. The parameters used were the mass density, specific heat, and thermal conductivity of the fibers and air. The heat flow calculated using the model was compared with that measured experimentally. Fairly good agreement was observed, verifying the validity of this heterogeneous model. The simulation results indicated that when the anisotropy of the fiber thermal conductivity is high, heat is transferred significantly faster along the longitudinal direction than along the transverse direction of the yarn, and the equilibrium temperature distribution is strongly influenced by heat transfer in the longitudinal direction.

Selection of helical braided flow diverter stents based on hemodynamic performance and mechanical properties

BackgroundAlthough flow diversion is a promising procedure for the treatment of aneurysms, complications have been reported and it remains poorly understood. The occurrence of adverse outcomes is known to depend...

Theoretical estimation of structural parameters in 2/2 twill woven structures

It has been shown through various experimental works that the geometry of woven fabrics will change after it is released from looms due to the contraction forces resulting in changed structural geometry in their fully relaxed state. In this work, an appropriate three dimensional unit cell is proposed for 2/2 twill woven structure. The proposed model covers all angles and lengths between warp and weft yarns in the three dimensional unit cell of the structure in its fully relaxed state assuming straight line path and circular cross-section of yarns. At first, a theoretical solution for estimation of skewness angle in float region of 2/2 twill fabrics is proposed by defining the JJ ratio index to consider different amount of contraction in float and crimp region of unit cell. Then the proposed theory is extended to include the weave and skewness angle of yarns in crimp region of woven structures. By applying this theory, the skewness angle of 2/2 twill weaves will be incorporated in structural modelling of woven fabrics which can be used in predicting the thickness and areal mass of the 2/2 twill woven structures. Besides the confirmed validation of model in predicting the areal mass, the results for estimating the thickness of fabrics are in close agreement with the measured ones in the fabrics with worsted and coarse cotton yarns.

Modeling of crack density in ceramic matrix composites

The feasibility of utilizing the shear lag theory to estimate crack density in fabric reinforced composites was investigated. A geometric model was constructed for the fabric and meshed using a hybrid finite element approach. The small segment of the yarn and the surrounding matrix enclosed within each element were treated as a unidirectional composite and the shear lag theory was used to estimate the crack density. Model results were compared to experimental data for a 5-harness satin melt-infiltrated SiC/SiC composite under tension and showed a pattern similar to experimental data with the model starting to accumulate cracks at a stress corresponding to the point of departure from linearity in the stress–strain curve while cracks were experimentally observed around 60 MPa higher. The model and experimental data had a similar value for the crack density at the saturation level. Sensitivity analysis showed that the crack density was highly sensitive to the fiber volume fraction in the load direction followed by the weave angle of the crimped segments of the yarns and the interfacial shear strength between the fibers and the matrix.

An investigation into thermoplastic matrix 3D woven carbon fibre composites

Three-dimensional woven textile reinforced composites allow the optimisation and tailoring of specific material properties into the final component. The objective of this work is to investigate the processing characteristics of Cyclic Butylene Terephthalate (supplied by Cyclics Corporation) that polymerises to form a thermoplastic, Polybutylene terephthalate, and to impregnate a multi-layer carbon fibre three-dimensional woven angle interlock fabric to produce a three-dimensional woven thermoplastic composite. Through adjustments in process cycle, the significant processing parameters have been identified, which optimise the production of thermoplastic Polybutylene terephthalate composite parts. Three-dimensional multi-layer reinforcements were manufactured on a modified textile loom to produce fabrics with fibres orientated in the warp, weft and through-the-thickness directions. Thermal and mechanical tests were conducted on the thermoplastic composite and comparisons were made to an epoxy composite with the same weave architecture. It was discovered from thermal analysis and optical microscopy that a highly crystalline matrix was developed as a result of the standard fabrication process with microcracks formed throughout the matrix. Reprocessing and annealing of the 3DCFCBT laminate reduced the crystallinity of the polymer structure.

Determination of in-plane shear modulus of 3D woven compositeswith large repeat unit cells

This paper presents the in-plane shear moduli of three-dimensionally (3D)woven angle interlock composites with different proportions of through thethickness binder content. The in-plane shear modulus Gxywas determined via three techniques: the plate twist test, the V notched beamIosipescu (ASTM D 5379) and the V notched rail shear (ASTMD 7078) test. The results indicate that the plate twist method is suitablefor the measurement of in-plane shear modulus for different 3D weave architectureswith large repeat unit cells, and that the measurement is more representativeof the global material response.

Elastic analysis of 3D woven orthogonal composites

PurposeThe purpose of this paper is to present an analytical modelling approach to predict engineering elastic constants of 3D woven orthogonal composites (3DWOCs) at representative volume element (RVE) level using a volume averaging method.Design/methodology/approachThe present analytical modeling approach uses a more realistic internal geometry representation of the 3DWOC. A RVE which is a repeating element at macroscopic level is first identified and volume proportions and engineering elastic constants of various constituents (matrix and family of constituent tows; warp, weft and z‐fibers) which contribute to the global stiffness of RVE/composite are next determined. For accurate predictions, emphasis is given to accurate measurements of micro‐structural data such as fiber volume fraction and fiber volume proportion of constituent tows and internal geometry of the 3DWOC structure‐in particular, undulation of z‐fibers. Microscopic study has been conducted in this regard.FindingsThe predicted engineering elastic constants are compared against experimental data, showing a strong correlation between predicted and experimental values.Practical implicationsThe methodology presented in the paper can be used for accurate computation of the engineering elastic constants of 3DWOCs. The method can also be used for other types of 2D or 3D textile composites such as 2D woven composites, 2D braided composites, 3D woven angle interlock composites and 3D braided composites.Originality/valueThe paper succeeds in relating the micro‐structural properties and analytical model for the accurate prediction of engineering elastic constants.

Determination of internal mechanical characteristics of woven fabrics using the force-balance analysis of yarn pullout test

Pullout test is a conventional and suitable method to investigate the effects of yarn properties and the structural characteristics of weave on fabric mechanical behaviour. Frictional specifications of the fabric yarns influence the fabric strength and efficiency and its ability to absorb energy. This paper is concerned with formulating an analytical model on yarn pullout force in plain-woven fabrics. The model can predict variations in the internal mechanical parameters of woven fabrics based on a force-balance analysis. These parameters are yarn-to-yarn friction coefficient, normal load at crossovers, lateral forces, lateral strain, weave angle variations, and pullout force. These parameters were predicted using fabric deformation data, which were measured by image processing method during a yarn pullout test and the information of weave angle of fabric, its modulus and density, which were obtained experimentally. Yarn pullout force was calculated through Amonton's friction law to evaluate the efficiency of the presented model. This study demonstrates that the force-balance model is correlated quantitatively with the experimental yarn pullout results.

In-Plane Effective Thermal Conductivity of Symmetric, Diamond-Weave Screen Laminates

Algebraic models of porosity, specific surface area, and in-plane effective thermal conductivity for stacked, two-dimensional symmetric diamond-weave screen laminations are developed and benchmarked with laboratory experiments. Diamond-weave laminations are found to have greater metal fractions and specific surface area than equivalent orthogonal-weaves. With the weave angle smaller than 90°, the structure also has a much higher effective thermal conductivity.

A Generalized Model of Plain Woven Fabric

A generalized model of plain woven fabric is proposed, based on a more realistic approximation of yarn bending behavior than that previously used. Peirce's rigid thread model is a special case. Approximate formulae for calculating the ratio of crimp height to thread spacing and weave angle are developed.

Pulsating Fatigue Strength of Low Carbon Steel Wires with Weave Angle

A composite material, ferrocement, is a thin cement mortar with multiple layers of reinforcing mesh. The strength of composite materials is dependent upon the strength of reinforcing materials. The purpose of this paper is to investigate the fatigue strength of reinforcing meshes used for ferrocement. Specimens with weave angle are extracted from square woven wire cloths, and tested under pulsating load. The woven wires used for these specimens are about 1 mm diameter-cold drawn and galvanized low carbon steel wires. The sizes of mesh openings. are 6, 8 and 10 mm. For the comparison, 2%- and 5%- prestrained woven wires and a straight wire are also tested. The summary of concluding remarks is as follows.The knuckle points of the specimens are subjected to bending moment as well as axial load. Therefore the S-N curve between the nominal stress S and the number of cycles to failure N does not have linearity. On the high stress level close to the yield point where the weave angle is diminished, the fatigue strength is improved by work hardening, though the shortest fatigue life appears on the middle stress level. Therefore this S-N curve may be difficult to be applied to design purposes.On the middle stress level of S-N curves, the fatigue life shows minimum cycles when the extreme fiber stress of a knuckle point calculated by elastic analysis has maximum value. The maximum strains, or peak strains, calculated by elastic stress analysis at a knuckle point are used to convert a S-N curve into a e-N curve. The obtained e-N curve is given by e·N0.148=0. 0206. The equation provides a significant coverage for all the experimental data of the specimens with different weave angles. The fatigue strength at N=2 × 106 cycles becomes e=0. 0024. This value is close to the proof stress (2% strain), the fatigue strength (2 ×106 cycles) of the straight wire and the 5%-prestrained woven wire. This e-N curve can be applied easily to design.

Shielding Effectiveness of Braided-Wire Shields

An analysis of the shielding effectiveness of braidedwire shields is made using the parameters of the woven wire and the theory of electromagnetic coupling through small irises. The coupling through the rhombic-shaped holes in the braid is approximated by using the electric and magnetic polarizabilities of elliptical holes of the same width and length as the rhombus. The analysis develops the transfer impedance and the mutual capacitance of the shield. The transfer impedance is calculated and plotted for shields of different optical coverages. The variation of mutual capacitance and mutual inductance with the weave angle of the braid are examined.