Continuous filament reinforced

There is a modified centrifugal casting process that produces continuous filament reinforced TP pipes/tubes with precise fiber placement and smooth internal and external surfaces. TPs such as nylon and polypropylene have been reinforced with fibers such as glass and carbon. Products such as automotive drive shafts and bearings have been fabricated with fiber volumes up to 60wt%. These tubes have very low rotational unbalances and tight tolerance of wall thickness (Chapter 15). 

A third form of both thermoplastics and thermosetting compounds takes the form of a sheet material that is press-moulded or stamped. It comprises a mat of reinforcement (which can include non-woven or woven structures, with chopped or continuous filament reinforcement) impregnated with the thermoplastic or thermosetting resin. 

Filament winding method of producing spherical or cylindrical reinforced plastics mouldings by winding continuous filament reinforcement onto a mandrel previously... 

Pultrusion is a process used for making continuous filament reinforced composite extruded profiles (see Fig. 1.13). 

Fibrous Composites. These composites consist of fibers in a matrix. The fibers may be short or discontinuous and randomly arranged continuous filaments arranged parallel to each other in the form of woven rovings (coUections of bundles of continuous filaments) or braided (8). In the case of chopped strand mat the random arrangement is planar. In whisker (needle-shaped crystals or filaments of carbon and ceramics) reinforced materials the arrangement is usually three-dimensional and the resulting composites are macroscopically homogeneous. 

If the matrix in 3.7 was reinforced with the same volume fraction of glass but in the form of randomly oriented glass fibres rather than continuous filaments, what would be the tensile strength of the composite. The fibres are 15 mm long, have an aspect ratio of 1000 and produce a reinforcement efficiency of 0.25. The fibre strength is 2 GN/m and the shear strength of the interface is 4 MN/m". 

By using special techniques, in which the reinforcing glass fibres are wound on in the form of a continuous filament, high strength can be obtained, and this method is used to produce pressure vessels. 

The properties of polymers reinforced with continuous filaments, rovings, fabrics and so on depend on ... 

Fiber-Matrix Composites. As shown in Figure 1.75, there are two main classifications of FMCs those with continuous fiber reinforcement and those with discontinuous fiber reinforcement. Continuous-flber-reinforced composites are made from fiber rovings (bundles of twisted filaments) that have been woven into two-dimensional sheets resembling a cloth fabric. These sheets can be cut and formed to a desired shape, or preform, that is then incorporated into a composite matrix, typically a thermosetting resin such as epoxy. Metallic, ceramic, and polymeric fibers of specific compositions can all be produced in continuous fashions, and the properties of the... 

The first continuous filaments were rayon, and these, as well as polyacrylonitrile (PAN) fibers, have been pyrolyzed to produce graphite fibers. High-modulus reinforcing filaments have also been produced by the deposition of boron atoms from boron trichloride vapors onto tungsten or graphite filaments. 

For unidirectional reinforced composites (by means of continuous filaments) the following formulae may be used ... 

Continuous-fiber reinforcement gives plastic products which are not simply quantitatively, but often qualitatively, superior to most present commercial practice. Most plastic processing is limited to conventional melt flow of short-fiber reinforcements, which sacrifices much of the potential benefits of reinforcement. There are a few processes for incorporating continuous fiber reinforcement—filament-winding, pultru-sion, swirl conformation of fibers in polymer... 

Star Stran. [Schuller] Continuous filament glass strand reinforcement for pofypn lene, PPS, rcL... 

Manufacturers of composite structures have traditionally used prepreg tape to manufacture structural components. Fibres are initially combined into unidirectional tows (bundles) of fibres combined into fabrics, e.g. by weaving or knitting. The vast majority of the tows employed in woven, braided or knitted reinforcements comprise low twist or untwisted continuous filament yams. Three-dimensional technical textiles can be produced by weaving [5], knitting [6] and braiding [7] or as non-crimp fabrics. 

Fibers are delivered as pulps, which are chopped and refined hhers with a high surface area. The pulps are used as specialty additives that enhance performance hy providing excellent reinforcement. Lightweight strength reinforcement can he achieved with continuous filaments. Honeycomb cores are available for aerospace industries. Spun yarn is used for protective coatings. ... 

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