PSI - Issue 14

Sanjeev M Kavale et al. / Procedia Structural Integrity 14 (2019) 584–596 Sanjeev M. Kavale, Krishnaraja G Kodancha, Nagaraj Ekbote / Structural Integrity Procedia 00 (2018) 000–000 specimen. From Fig. 9, it can be observed that the Triaxiality Factor is dependent on Poisson’s ratio, and is increasing with increasing Poisson’s ratio. It can also be observed that for = 0, the Triaxiality Factor is constant across the thickness of the specimen, which could be the reason for getting constant K I and T 11 -Stress along the thickness for = 0 shown in the Fig. 5 and Fig. 8. From Fig. 10 and Fig. 11, it is evident that the Triaxiality Factor is dependent on Poisson’s ratio along the ligament and as the Poisson’s ratio increases the Stress Triaxiality Factor increases along the ligament. 591 8

3.00 (B)

1.0 (A)

 = 0  = 0.20  = 0.25  = 0.30  = 0.35  = 0.40  = 0.45

 = 0  = 0.20  = 0.25  = 0.30  = 0.35  = 0.40  = 0.45

2.25

0.5

1.50

0.0

SENB a/W=0.50 B=12.7mm

0.75

SENB a/W=0.50 B=12.7mm

0.00

-0.5

Triaxiality Factor (h)

Triaxiality Factor (h)

Surface of the Specimen

Center of the Specimen

-0.75

-1.0

0

2

4

6

8 10 12 14

0

2

4

6

8 10 12 14

Ligament, mm

Ligament, mm

Fig. 10 Variation of Stress Triaxiality Factor ( h ) along the ligament for various Poisson’s ratio for a/W =0.50 and B/W =0.50 for SENB specimen at (A) the surface of the specimen and (B) the center of the specimen.

2.5 (B)

1.0 (A)

 = 0  = 0.20  = 0.25  = 0.30  = 0.35  = 0.40  = 0.45

 = 0  = 0.20  = 0.25  = 0.30  = 0.35  = 0.40  = 0.45

0.8

2.0

0.6

1.5

0.4

1.0

0.2

CT a/W=0.50 B=12.7mm

0.5

CT a/W=0.50 B=12.7mm

0.0

0.0

Trixiality Factor (h)

-0.2

Triaxiality Factor (h)

-2 0 2 4 6 8 10 12 14 -0.5 Center of the Specimen

Surface of the Specimen

-0.4

-2 0 2 4 6 8 10 12 14

Ligament, mm

Ligament, mm

A typical variation of normalized maximum stress intensity factor, ������ / √ , which is observed at the center and different B/W for various Poisson’s ratio and a/W = 0.50 are shown in the Fig. 12 for SENB and CT specimen. The corresponding variation in normalized T 11 at the center of the specimen, T 11(max) / σ is indicated in Fig. 13. Similarly, the magnitudes of T 33 at the center of the specimen are estimated using Eq. 4. The �� values needed in the Eq. 4 are extracted from all the analyses done from the ABAQUS post processor for varied B and Poisson’s ratio. 11 33 33 T E T     (4) Fig. 11 Variation of Stress Triaxiality Factor ( h ) along the ligament for various Poisson’s ratio for a/W =0.50 and B/W =0.50 for CT specimen at (A) the surface of the specimen and (B) the center of the specimen.