PSI - Issue 75

Aijia Li et al. / Procedia Structural Integrity 75 (2025) 318–333

325

8

Aijia Li, Christian Garnier,, Marie-Laetitia Pastor, Xiaojing Gong, Clément Keller/ Structural Integrity Procedia (2025)

Elastic modulus in the normal direction Shear modulus in the first direction Shear modulus in the second direction

9500

MPa MPa MPa MPa MPa MPa -

E

15000 15000

G 1 G 2

Damage type

Quads Damage

- - - - - -

Damage nominal stress in the normal-only mode Damage nominal stress in the first direction Damage nominal stress in the second direction

75 50 50

Damage evolution type Mixed mode behavior

Energy

- -

BK model

Fig. 5. specific feature of the gauge region in the final simulation

4. Result and validation 4.1. Result of the initial simulation procedure

The results of the initial simulation procedure are summarized in Table 3. For the first criterion linked to failure localization in the gauge region, it is clear that only a reduced area with a single circular transition can lead to an expected failure location, as shown in Fig. 6. The dimension of the reduced area and transition is also determined to a range for the final simulation procedure. As can be seen in Fig. 7, the stress distribution and location of the maximum Von-Mises stress (see the white dart) reveal that a hole in the gauge region induces a discontinuity, so the “circular hole” and “protrusion” are not good choices when considering the second design criterion. With respect to the third design criterion, the “reduced area” option is more suitable than the other two options, as it ensures a complete and planar area for recording the temperature. The last criterion focuses on the manufacturing feasibility, and all configurations can be fabricated using the manufacturing method mentioned in the last chapter. As a result, the selected shape with a “reduced area” and “single circular transition” in Fig. 6 is going to be further optimized and discussed to ascertain the dimension.

Table 1. result of the initial simulation procedure

Criterion 1 : Failure in the gauge region

Criterion 2 : Uniform stress field

Criterion 3 : Manufacturing difficulty

Criterion 4 : Thermography observation

No

Gauge region

Transition region

Reduced area (6 mm < d < 20 mm)

Single circular (10 mm < R < 20 mm)

1

Yes

Yes

Normal

Good