Crack Paths 2006

1 0 - 5 :

l l l l l l l l l Il l l l l l 1l0 - 5::

l l l l l l l l l l l l l l :

:

3355'.

AlCuMg1

:

:

:

i I‘

ALUMINIUAML L O Y :

i

i

A

3 - R = 0

A

A

A

106i %

I

10'6I,

AI

12‘

:

:

T2‘

:

:

5 f E A

f A A

5 f e A

f A A

e

A

e

A

g 107i

1

j g 107i

1

AI

’ i

’ ’

:

AlCuMg1

:

ALUMINIUAML L O Y

10-8

l

I 1 1 1 ‘

1 1 1 ] ]

10-8

l

l l l l l ]

l

l l l l l

10’3

10'2

10'1

10,3

"1'2

104

A J (MPa-m)

A J (MPa-m)

Figure 7. Comparisonof experimental results for different stress ratios and 0t I 450 a)

modeI, b) mode111

a)

b)

1 o - 5 :

l l l l l l l l l Il l l l l l l1 0 - 5::

l l l l l l l

l l l l l l l :

:F ggdgo'.

AlCuMg1

:

:

AlCuMg1

f

i A

ALUMINIUAML L O Y :

A ALUMINIUAML L O Y

-

A

A

A

2

A

166i

5

106i

5

E i

i

E i

:

S i

f

5 f

f

E i

- ,

e A

- A

z

,

A1

g

,

g

\

% 1 0 7 i

5 g 1 0 7 i

i

j

g

j

i

j

10’8

l

l

l

l

l

l

‘

l

l

l

l

l

l

108

10'3

10'2

10‘1

10,3

104

A J (MPa-m)

Figure 8. Comparisonof experimental results for different stress ratios and 0t I 60° a)

modeI, b) mode111

Moreover, we can state that for the stress ratio R I -1 and angle a I 30° the crack

growth rate is higher for mode111 than for modeI under the same value A]; for angle or

I 60° a higher rate is observed for mode I. For or I 45°, we observe a higher crack

growth rate for mode I to da/dN I 810'8 m/cycle (Fig. 7), above which mode 111 is

dominating together with increase of the material plasticity. For R I - 0.5 and 0, for all