Fiber bundle strength

It is of interest to compare this result to that found for a dry bundle. Then, the fiber bundle strength Sb, depends on the gauge length in accordance with,72... 

Following Daniels (1945) we use a normal distribution for the fiber bundle strength, o-g. This is reasonable when the number of fibers, N, in a bundle is large. The mean value for a normal distribution is... 

Therefore, from Eqs. (10.22) and (10.28), we obtain the mean fiber bundle strength as... 

Figure 10.6 Fiber bundle strength/fiber strength as a function of coefficient of variation of fiber strength. The fiber bundle strength falls as the coefficient of variation of fiber strength increases.

Taking the ratio of the mean fiber bundle strength (Eq. (10.30)) and mean individual fiber strength (Eq. (10.9)), we can write... 

Prospective flax fiber tests include a standard test method for flax fiber bundle strength and elongation similar to the Stelometer, fiber length and distribution, fineness distribution via image analysis, wax content via NIR, density measurement, and numerous flax mat characterization tests. Prior work has indicated that NIR spectroscopy has potential for determining wax content in flax fibers (Sohn et al. 2006). Potential standards could exist for farmers to predict fiber content in stems in the field by near-infrared spectroscopy (Barton et al. 2002). The Composites Innovation Center (QC) in Winnipeg is working on a system to characterize flax fiber mats and subsequent composites. 

Aramid Yarn—Strength elements that provide tensile strength and provide support and additional protection of the fiber bundles. Kevlar is a particular brand of aramid yam. 

In general, composite consolidation degrades fiber properties and it becomes necessary to devise procedures that allow determination of Sc and m to be evaluated relevant to the fibers within the composite. This is a challenging problem. In some cases, it is possible to dissolve the matrix without further degrading the fibers and then measure the bundle strength.77 This is not feasible with most CMCs of interest. The following two alternatives exist. 

The specimen is composed of a mixture of matrix, unbroken fibers, and broken fibers. The volume fraction of intact fibers is given by Eqn. (57) with L = Ls, the specimen length. To the neglect of transients, the macroscopic stress supported by these intact fibers is given by Eqn. (60). The strain will now exceed the level of Eqn. (61) associated with the ultimate strength of the fiber bundle. Therefore, the stress supported by the intact fibers will be less than ac, which is the ultimate strength of the fiber bundle without matrix. The applied stress exceeds composite material to creep. 

SiC fibers are continuous fibers bundled in groups of500 filaments, with each filament having a diameter of 15 (xm. The fibers have high strength. 

The last step in stone groundwood production is a screening of the fiber suspension in water to remove shives (fiber bundles or small splinters) from the stock. If paper is made from stock containing shives it will have low-strength properties in the area around each shive because of poor interfiber... 

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