Effect of Fiber Waviness on Processing and Performance of Textile Composites

2022 ◽  
Author(s):  
Ryan S. Enos ◽  
Dianyun Zhang
2011 ◽  
Vol 217-218 ◽  
pp. 1758-1762
Author(s):  
Tao Chang

As the most potential member in the textile composite material, stitched textile composites have already been paid a lot attention. By the simply technology form and relatively low cost, stitched composites had attracted many domestic and foreign researchers, and were gradually used in various engineering practice. This paper using 3D micro-finite element method researches the mechanical behavior and performance of stitched composites, establishing a 3D micro-finite element model for the stitched composites under the improved locking suture way. Through analysis, it shows that each material’s stress distribution characteristics under external loading and finds that the results of this paper’s finite element data results matching well with previous studies’ results, proving the feasibility of this study, so it can be used for forecasting the mechanical properties of a variety of practical stitched composites.


2019 ◽  
Vol 14 ◽  
pp. 155892501988996
Author(s):  
Zhenyu Ma ◽  
Pingze Zhang ◽  
Jianxun Zhu

Three-dimensional textile fabrics are used as the reinforcing phase of the textile structural composites, and their geometry affect the physical and mechanical properties of composites. Based on the curvature and directions of the fiber tows in three-dimensional textile fabrics, four representative geometric units are proposed, namely, the orthogonal geometric unit, the curved geometric unit, the skew geometric unit, and the uniform distribution unit, respectively. Other units are the combinations or derivations of these representative geometric units. The relationship and performance characteristics of these representative geometric units are discussed in section “The relationship of RGUs.” The structural features of three-dimensional textile fabrics are illustrated on the mesoscopic scale, and the models are established to predict the geometric properties. The concepts of fabrics with stable structure, flexible structure, elastoplastic structure, and uniform structure are proposed. The fiber volume fractions and elastic characteristics of different structural fabrics are discussed. The classification of three-dimensional textile fabrics is conducive to investigate the relationship between geometry and property, forming a technical system and providing a theoretical basis for the selection of three-dimensional structural textile composites with different performance.


2015 ◽  
Vol 671 ◽  
pp. 306-314
Author(s):  
Kai Luo ◽  
Shu Jie Zhang ◽  
Rui Wang ◽  
Xiang Ping Si ◽  
Xu Han

Tubular Textile Composites Lines in the Internal of Damaged Pipeline by the Trenchless Pipeline Inversion Lining Rehabilitation Technology,in the Form of “pipe in Pipe”for the Repair of Damaged Pipeline. Meanwhile, this Technology Uses Trench-Less Pipeline Repairing Technology and Process to Instead of Full Excavation for Replacing New Pipe , which is Not only Economic but Also Environmental Protection, Meeting the Demands of Modern Urban Development. in this Paper, it’s Mainly Uses a Variety of Trenchless Pipeline Inversion Lining Rehabilitation Technology to Describe Tubular Textile Composite Raw Materials, and to Compare its Molding Methods and Performance Evaluation. and then Making a few Suggestions for the Research and Development on Trenchless Pipeline Inversion Lining Rehabilitation Technology with Tubing Textile Composites.


2000 ◽  
Vol 36 (4) ◽  
pp. 297-318 ◽  
Author(s):  
S. P. Yushanov ◽  
A. E. Bogdanovich

Author(s):  
H. M. Thieringer

It has repeatedly been show that with conventional electron microscopes very fine electron probes can be produced, therefore allowing various micro-techniques such as micro recording, X-ray microanalysis and convergent beam diffraction. In this paper the function and performance of an SIEMENS ELMISKOP 101 used as a scanning transmission microscope (STEM) is described. This mode of operation has some advantages over the conventional transmission microscopy (CTEM) especially for the observation of thick specimen, in spite of somewhat longer image recording times.Fig.1 shows schematically the ray path and the additional electronics of an ELMISKOP 101 working as a STEM. With a point-cathode, and using condensor I and the objective lens as a demagnifying system, an electron probe with a half-width ob about 25 Å and a typical current of 5.10-11 amp at 100 kV can be obtained in the back focal plane of the objective lens.


Author(s):  
Huang Min ◽  
P.S. Flora ◽  
C.J. Harland ◽  
J.A. Venables

A cylindrical mirror analyser (CMA) has been built with a parallel recording detection system. It is being used for angular resolved electron spectroscopy (ARES) within a SEM. The CMA has been optimised for imaging applications; the inner cylinder contains a magnetically focused and scanned, 30kV, SEM electron-optical column. The CMA has a large inner radius (50.8mm) and a large collection solid angle (Ω > 1sterad). An energy resolution (ΔE/E) of 1-2% has been achieved. The design and performance of the combination SEM/CMA instrument has been described previously and the CMA and detector system has been used for low voltage electron spectroscopy. Here we discuss the use of the CMA for ARES and present some preliminary results.The CMA has been designed for an axis-to-ring focus and uses an annular type detector. This detector consists of a channel-plate/YAG/mirror assembly which is optically coupled to either a photomultiplier for spectroscopy or a TV camera for parallel detection.


Author(s):  
Joe A. Mascorro ◽  
Gerald S. Kirby

Embedding media based upon an epoxy resin of choice and the acid anhydrides dodecenyl succinic anhydride (DDSA), nadic methyl anhydride (NMA), and catalyzed by the tertiary amine 2,4,6-Tri(dimethylaminomethyl) phenol (DMP-30) are widely used in biological electron microscopy. These media possess a viscosity character that can impair tissue infiltration, particularly if original Epon 812 is utilized as the base resin. Other resins that are considerably less viscous than Epon 812 now are available as replacements. Likewise, nonenyl succinic anhydride (NSA) and dimethylaminoethanol (DMAE) are more fluid than their counterparts DDSA and DMP- 30 commonly used in earlier formulations. This work utilizes novel epoxy and anhydride combinations in order to produce embedding media with desirable flow rate and viscosity parameters that, in turn, would allow the medium to optimally infiltrate tissues. Specifically, embeding media based on EmBed 812 or LX 112 with NSA (in place of DDSA) and DMAE (replacing DMP-30), with NMA remaining constant, are formulated and offered as alternatives for routine biological work.Individual epoxy resins (Table I) or complete embedding media (Tables II-III) were tested for flow rate and viscosity. The novel media were further examined for their ability to infilftrate tissues, polymerize, sectioning and staining character, as well as strength and stability to the electron beam and column vacuum. For physical comparisons, a volume (9 ml) of either resin or media was aspirated into a capillary viscocimeter oriented vertically. The material was then allowed to flow out freely under the influence of gravity and the flow time necessary for the volume to exit was recored (Col B,C; Tables). In addition, the volume flow rate (ml flowing/second; Col D, Tables) was measured. Viscosity (n) could then be determined by using the Hagen-Poiseville relation for laminar flow, n = c.p/Q, where c = a geometric constant from an instrument calibration with water, p = mass density, and Q = volume flow rate. Mass weight and density of the materials were determined as well (Col F,G; Tables). Infiltration schedules utilized were short (1/2 hr 1:1, 3 hrs full resin), intermediate (1/2 hr 1:1, 6 hrs full resin) , or long (1/2 hr 1:1, 6 hrs full resin) in total time. Polymerization schedules ranging from 15 hrs (overnight) through 24, 36, or 48 hrs were tested. Sections demonstrating gold interference colors were collected on unsupported 200- 300 mesh grids and stained sequentially with uranyl acetate and lead citrate.


Author(s):  
D. E. Newbury ◽  
R. D. Leapman

Trace constituents, which can be very loosely defined as those present at concentration levels below 1 percent, often exert influence on structure, properties, and performance far greater than what might be estimated from their proportion alone. Defining the role of trace constituents in the microstructure, or indeed even determining their location, makes great demands on the available array of microanalytical tools. These demands become increasingly more challenging as the dimensions of the volume element to be probed become smaller. For example, a cubic volume element of silicon with an edge dimension of 1 micrometer contains approximately 5×1010 atoms. High performance secondary ion mass spectrometry (SIMS) can be used to measure trace constituents to levels of hundreds of parts per billion from such a volume element (e. g., detection of at least 100 atoms to give 10% reproducibility with an overall detection efficiency of 1%, considering ionization, transmission, and counting).


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