PSI - Issue 47

Sergio Arrieta et al. / Procedia Structural Integrity 47 (2023) 13–21 Author name / Structural Integrity Procedia 00 (2019) 000–000

17

5

By introducing different values of R c in (5) and (6), two W c vs R c curves are generated (see Fig. 3). The crossing point of both curves provides the actual values of W c * and R c *.

8

7

W1 (0.25 mm) W2 (1.00 mm) Cut-off W c * = 4.34 MPa R c * = 0.60 mm

6

5

4

3 W (MPa)

2

1

0

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

R c (mm)

Fig. 3. Calibration of W c and R c parameters with SENB specimens.

* =4.34 MPa and R

From this calibration, the parameters are W c

c *=0.60 mm. These parameters are used to calculate

the critical load predictions.

3. Results and discussion

Fig. 4 shows an example of the experimental setup. Table 3 gathers the experimental critical loads (P exp for individual tests and P exp,avg for mean value of each geometry). As explained above, the calibration performed to obtain the ASED parameters provided values of W c *=4.34 MPa and R c *=0.60 mm. Once W c * and R c * are known, fracture loads are derived from:  = 2 2,  ∗       =  ∗ (7) Considering that F(2 α ) is 0.785 for U-notches, the corresponding σ max is easily derived from:   =  ·  ∗ .·,   ∗  (8)