Fatigue Crack Paths 2003

Figure 7. Matching surfaces – micromorphology of ductile fatigue striations

(arrows indicate local direction of fatigue crack growth).

Figure 8. Matching surfaces – micromorphology of ductile fatigue striations

(detail from Fig. 7).

S U M M A R Y

The results suggest that the resistance against fatigue failure of studied material depends

on the last step of mechanical forming or on the cooling rate after this operation - the

plate (oil quenched - recovered elongated grains) is more resistant against fatigue failure

than an alloy of a similar chemical composition in the form of tube (air cooled -