Fatigue Crack Paths 2003

It is seen that there is a scatter of parameter values, typical for fatigue tests for P M M A .

The present model predicts much better fatigue crack growth, especially for high values

of KImax close to

*IcK. W enote that the value of parameter p equals one, and the follow

ing relations are valid:

( ) ( ) n ω τ τ ω σ ω−σσ τ= τ − = , 1 , 1 * c c * o o o o n

(58)

( ) ( ) n = 1 , 1

− =

* c c

The specification of damage zone growth is then essentially simplified, cf. Eq. (57). It is

also interesting to note that the maximumsize of damage zone d0 = 0.16 m mwas con

firmed from both static and cyclic loading tests, providing good correlation with ex

perimental data.

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