Crack Paths 2012

SIF is changed, i.e., the maximumSIF is observed around at the degree of zero (θ= 0)

and the minimumSIF is observed around at the degree π (θ= π). As a result, it can be

thought that the lifetime to failure rather increases as angular misalignment increases.

The distribution of SIFs and the lifetime to failure are affected by the contribution of

two misalignments. In other words, the direction of misalignments can be critical to the

reliability of test results using C N Bspecimens.

1.8

1.8

C0.020_A( )0.1

C0.020_A(0)0.4

N/Nf0=0

N/Nf0=0.163

N/Nf0=0.651

1.6

1.6

N/Nf0=0.163

N/Nf0=0.326

N/Nf0=0.326

1.4

1.4

N/Nf0=0.489

N/Nf0=0.355

1.2

1.2

1.0

1.0

0.8

0.8

0.6

0.6

0.4

0.4

0.2

0.2

0.0

0.0

0 S/4 S/2

3S/4 S

5S/4 3S/2 7S/4 2S

0 S/4 S/2 3S/4 S 5S/4 3S/2 7S/4 2S

Degree(T)

Degree(T)

(a) C0.020_A(0)0.1

(b) C0.020_A(0)0.4

1.8

1.8

C0.020_A(S/2)0.1

C0.020_A(S/2)0.4

N/Nf0=0

N/Nf0=0.651

N/Nf0=0.163

N/Nf0=0.568

1.6

1.6

N/Nf0=0.163

N/Nf0=0.765

N/Nf0=0.326

N/Nf0=0.326

1.4

1.4

N/Nf0=0.489

N/Nf0=0.489

1.2

1.2

1.0

1.0

0.8

0.8

0.6

0.6

0.24

0.4

0.2

0.0

0.0

0 S/4 S/2

3S/4 S

5S/4 3S/2 7S/4 2S

0 S/4 S/2 3S/4 S 5S/4 3S/2 7S/4 2S

Degree(T)

Degree(T)

(d) ) C0. 020_ A(π/2)0.4

(c) ) C0.020_A(π/2)0.1

1.8

1.8

C0.020_A(S)0.1

C0.020_A(S)0.4

N/Nf0=0

N/Nf0=0

N/Nf0=0.651

N/Nf0=0.651

1.6

1.6

N/Nf0=0.163

N/Nf0=0.163

N/Nf0=0.814

N/Nf0=0.814

N/Nf0=0.326

N/Nf0=0.326

N/Nf0=0.896

N/Nf0=0.977

1.4

1.4

N/Nf0=0.489

N/Nf0=0.489

1.2

1.2

1.0

1.0

0.8

0.8

0.6

0.6

0.4

0.4

0.2

0.2

0.0

0.0

0 S/4 S/2

3S/4 S

5S/4 3S/2 7S/4 2S

0 S/4 S/2

3S/4 S

5S/4 3S/2 7S/4 2S

Degree(T)

Degree(T)

(e) C0. 020_A(π)0.1

(f) C0. 020_A(π)0.4

C : normalized concentric misalignment / A : angular misalignment

Figure 8. The variation of normalized SIFs at the crack contour for combined

misalignments

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