Braid architecture

Fiber braided/directional Weaving fibers into a tubular shape. As an example, A8cP Technology, Cincinnati, OH, specializes in developing braided reinforcements using a variety of material types, braid forms, and braid architectures for applications ranging from prostheses to... 

Figure 10.19 Braid architecture (a) Localization of the braiding yarn, middle-end yarn, and core yarn for one pitch length, (b) The fiber path for one braid plait is represented by a cosine.

Films, knitted, woven, braided or sewn fibres for architectural fabrics. .. 

You look up. The world rising above you is a tangle of strange architectures decorated with braids of 5-D flowers—or so you think. There are a number of tall spirals of stone that measure at least 100 yards in diameter at their bases. There are amber, pagoda-like plants, wonderfully tinted with red about their leaves. The plants seem to be part of the vast ancient architectural structures. 

In this section we select the most important criteria of correspondence of a model to reality. Then, we overview both the peculiarities of textile reinforcement that must be accounted in an ideal damage model and the requirements to the solid models asserted by various FE approaches. Meso-scale 3D FE models available in literature are classified according to the selected geometric features. Models of 2D braided composites are included in the overview to give a wider perspective. In many aspects, challenges for modelling 2D braided and 2D woven yam architectures are exactly the same. 

Birkefeld K, Roder M, Von Reden T, Bulat M, Drechsler K. Characterization of biaxial and triaxial braids fiber architecture and mechanical properties. Appl Compos Mater... 

Milwich et al. (2006) combined ideas of cellulose fiber orientation in wood with the structure of the stem of giant reeds to create a hybrid model realized using advanced braid protrusion machinery at the Institute of Textile Technology and Process Engineering (ITV) Germany. The outcome called Technical Plant Stem is a commercially scalable architectural textile composite that demonstrates excellent strength and impact resistance with the minimal material use (Speck and Speck, 2006). 

SiC/RBSN composites containing monofilaments are limited to simple shapes. However, SiC/RBSN shape capability can be improved by using textile processes (weaving, braiding) to form multi-fiber bundles or tows of ceramic fibers into 2-D and 3-D fiber architectures. 

Fig. 1.3 Predicted and moduli for a range of reinforcement architectures 0 angle ply (for 0=0 to 45 to 90), cross-ply (0/90), eight-harness satin, and plain woven, triaxial woven fabric, braided (0=35° to 15°) and multiaxial warp knit ( - ), for the same fibre volume...

The potential complexity of the braided shucture, particularly the three-dimensional architectures, is such that the characterisation of the structures is often taken to be a major first step in modelling the behaviour of the reinforced material. The desired outcome of this work is to present a three-dimensional visualisation of the structure (e.g. Pandey and Hahtf ) or to develop models to describe the structural geometry (e.g. Du et aV ). Analytical models for predicting properties are frequently developments... 

Naik RA, Ifju PG, Masters JE. Effect of fiber architecture parameters on deformation fields and elastic moduli of 2-D braided composites. J Compos Mater 1994 28 656-81. 

The precursor fiber type for reinforcing the carbon matrix can be an oxidized PAN fiber (opf), or either a PAN or pitch based carbon fiber. In some instances, for special applications, such as the Shuttle, a cellulose based carbon fiber is used. The reinforcements can be unidirectional have a random chopped fiber presentation as in a felt format a woven product from continuous fiber presented in a 2D, 3D, or in a Multi-D format (Section 21.1), or a non-woven carbon fiber. The chosen fiber architecture is most important for a given application and Lei et al [4] describe how, for example, 3-D braiding can be applied to carbon-carbon composites. One of the early forms of near net shape reinforcement used for carbon-carbon aircraft brakes was based on a weft knitted 3-D fabric made by the Pressure Foot process (Figure 14.1). 

Hearle and Du [2] discuss the interaction of textile technology and composite engineering and Brookstein [58] discusses braided and woven interlocked fiber architecture. 

Brookstein DS, Interlocked fibre architecture, braided and woven, 35th Int SAMPE Symp, Apr 1990. 

Multistep braiding is an extension of the four-step braiding process. By allowing for individual control of track-and-column displacement, strong yam architectural versatility may be achieved (Kostar and Chou, 1994). 

Braiding procedures to produce braids with various cross sections have already been developed for the Ist-generation hexagonal braider. It was shown that a wide range of cross-section geometries as well as fibre architectures are feasible (Schreiber et ah, 2009). 

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