PSI - Issue 13

P. González et al. / Procedia Structural Integrity 13 (2018) 3–10 P. González/ Structural Integrity Procedia 00 (2018) 000 – 000

9

7

0 100 200 300 400 500 600 700 800

581

549

Test 1

564

Test 2

Stress, MPa

Test 3

0

50000

100000

150000

Time, s

Fig. 7. Incremental Step Loading Technique and stress-time curves obtained.

From the results obtained by the finite elements analysis, the following considerations can be made:  Figure 8 shows that the corresponding stress-distance curves cross each other at a point with coordinates (L/2, 0 )  The value of L calculated from the finite elements analysis (L/2=0.072mm) provides adjusted predictions of K N ISCC . (see Fig 9) following the PM expression (Eq. 5).  The value of 0 obtained (2710 MPa) does not coincide with calculated (549 MPa).

Fig. 8. Stress – distance curves at rupture in X80 CT specimens. Figure 9 shows the experimental results of (pre-cracked specimens), (notched specimens) and predictions provided by the PM (Eq. 5). It can be observed that PM predictions show a high degree of accuracy.

X80 5mA/cm 2 6E-8m/s

0 20 40 60 80 100

0,5 )

X80 5mA/cm2 6E-8m/s PM

K N ISCC (MPa·m

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

ρ 0,5 (mm 0,5 )

Fig. 9. Experimental results on X80 at 5mA/cm 2 and 6E-8m/s test rate and predictions provided by the Point Method.