Mechanism Cook-Gordon

Fig. 6.13. The Cook-Gordon (1964) mechanisms tensile debonding occurs at the weak interface ahead of crack tip as a result of lateral stress concentration and crack tip is effectively blunted.

Figure 7.13 The Cook-Gordon arrest mechanisms of a crack, after Bentur (1988).

These observations can be explained on the basis of the weak interface in the transition zone (porous layer in Figure 2.5) and the Cook-Gordon crack arrest mechanism [82] shown in Figure 3.40. The stress field ahead of the elliptical crack tip consists ofthe familiar stress concentration profile in the direction of the external tensile stress (/direction), and a tensile stress field in the... 

Figure 3.40 The Cook-Gordon crack arrest mechanism in a composite with a weak interface [82]. (a) Stress field in front of the crack tip (b) schematic description of the crack arrest (I) crack approaches a weak interface (2) interface fails ahead of the main crack (3) T-shape crack stopper. In practice the crack is usually diverted.

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