Page 174 - Engineered Interfaces in Fiber Reinforced Composites
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156 Engineered interfaces in jiber reinforced composites
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Fig. 4.39. Comparisons of initial debond stress, uo, and maximum debond stress, ai, between fiber pull-
out and fiber push-out as a function of embedded fiber length, L, for (a) release agent coated steel fiber-
epoxy matrix composites and (b) untreated Sic fiber-glass matrix composites. After Kim et al. (1994~).
4.5. Cyclic loading in fiber pull-out and fiber push-out
4.5.1. Introduction
The analytical solutions derived in Sections 4.3 and 4.4 for the stress distributions
in the monotonic fiber pull-out and fiber push-out loadings are further extended to
cyclic loading (Zhou et al., 1993) and the progressive damage processes of the
interface are characterized. It is assumed that the cyclic fatigue of uniform stress
amplitude causes the frictional properties at the debonded interface to degrade
