Influence of Grain Boundary on the Fatigue Crack Growth of 7050-T7451 Aluminum Alloy Based on Small Time Scale Method

Figure 8

In the loading stage of 112 cycles, micromorphology of fatigue crack at different loading level: (a) at 175 N, (b) at 525 N, (c) at 700 N, (d) at 875 N, (e) at 1050 N, (f) at 1225 N, (g) at 1400 N, and (h) at 1750 N.

(a)

(b)

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(e)

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(h)