Hackle morphology fibers

SE images of a matched pair of tensile failed PET fibers are shown in Fig. 4.30. A classical slow fracture zone, or mirror, is seen adjacent to the locus of failure. A typical ridged or hackle morphology is exhibited as the crack propagates and accelerates away from the failure locus. In this study, an inorganic residue from the polymer process was shown to be the cause of failure [295]. The value of such a fractography is that... 

Fig. 5.59 SEM study of brittle failure in an impact modified nylon molded article reveals classical fracture morphology. The locus of failure (arrow) is seen (A) with surrounding mirror (M), mist and ridged hackle (H) regions propagating out into the bar. A higher magnification view of the flaw and mirror is shown (B). The flaw (C) appears to be a round fiber, likely a contaminant.

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