Crack defected by fiber

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FIGURE 3.2 This video frame shows fiber stopping a crack. This consumes energy and maintains CFCC integrity.

or metal-like behavior results. Therefore, the shape of the CFCC stress-strain curve beyond the elastic limit is determined by the ability of the ceramic fiber to "slip" through the matrix. This slip is facilitated by appropriate fiber coatings (see Figs. 3.2 and 3.3).

Typical properties of CFCCs are shown in Table 3.2. They are presented as a range since CFCCs are a family of products composed of various ceramic fibers, coatings, ceramic matrices, and made by various processes by several manufacturers. This offers the advantage of selecting from a range of CFCC materials or customizing a formula to meet your specific requirements. Future compositions may have properties outside this range.

FIGURE 3.3 When overstressed, fibers pull away from matrix. Fiber-matrix interface coating allows fiber to slip within matrix, taking any load onto fiber, lending strength to composite.
TABLE 3.2 CFCC Properties at Room Temperature


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