Crack Paths 2006
constraint level. With the aim to assess the influence of constraint on fatigue life under
mixed-mode conditions two-parameter constraint based on fracture mechanics was
applied. Two aspects of fatigue crack propagation, namely the fatigue crack propagation
direction and the fatigue crack propagation rate, were analysed. The behaviour of the
201
8
6
]
Pma
P a m
]
4
[ M
[ M
17 18 19
K
K
2
156
0
4
6
8
10
12
a [mm]
Figure 4. K-calibration for a C C Tspecimen with holes. ModeI loading – full line and
modeII loading dash line
-1-4862840
[ M P a ]
[- ]
/K
K0.01234
4
6
8 a [mm]
10
12
T
2 4 6 8 10 12 14
a [mm]
Figure 5. The ratio of the stress intensity factors KII/KI for a C C Tspecime with
Figure 6. The dependence of the T
stress for a C C Tspecimen with holes.
holes. Values correspond to a
numerically calculated crack path.
fatigue crack near a hole in a tensile specimen was experimentally studied and the
results obtained were compared with those of the corresponding numerical simulation.
The fatigue crack path was predicted by using the modified maximumtensile stress
criterion. The following results have been obtained:
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