Crack Paths 2009

1.8

E L CH D Gk t = 10 %

1.246

IF (TiNb) G Ak t = 10 % NbP)G Ak t = 10 %

S t r e n g t h

a)

IF ( T i N b P ) H DkGt = 10 % B ) G A k t = 1

S t r e s s A m p li t u d e / Y ie ld

1.0

0.8

104

105

106

107

Fatigue Life (Nf)

Figure 4. a) S-N data as a ratio of stress amplitude/yield strength for kt = 1.

E L Ck t = 3 IF(TiNb) U Ck t = 3 I H D Gk t = 3

1.024

ng t h

S t r e

b)

IF(TiNb) G Ak t = 3

S t r e s s A m p li t u d e / Y ie ld

0.8

0.6

104

105

106

Fatigue Life (Nf)

Figure 4. b) S-N data as a ratio of stress amplitude/yield strength for kt = 3.

In the presence of a notch with kt = 3 (Figure 4b) the IF and E L C grades perform

best in terms of fatigue performance as a function of yield strength. It is observed for

the IF (TiNb) alloy that both the H D Gand G A conditions perform better than the

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