PSI - Issue 61

Toros Arda Akşen et al. / Procedia Structural Integrity 61 (2024) 268 – 276 Toros Arda Akşen, Bora Şener, Emre Esener, Ümit Kocabıçak, Mehmet Fırat / Structural Integrity Procedia 00 (2019) 000 – 000 7

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Half part of the specimens was created except for the SH specimen. Since the SH specimen is not symmetric, the entire model of the SH specimen was generated in Marc. The element type is the fully integrated hexahedral solid elements for each specimen (Marc (2018)). Four elements were employed through thickness. Analyses of tensile tests were carried out, and Fig. 4 compares the experimental and numerical results.

a

b

c

Fig. 4. Comparative force-displacement responses, (a) STT; (b) NT5; (c) NT10

a

b

c

Fig. 5. Comparative force-displacement responses, (a) NT20; (b) CH; (c) SH.

The analysis results demonstrated successful approximations with the experimental force-displacement responses. The results of the STT were considered only for assessing the performance of the hardening parameters, while the results of the NT5, NT10, NT20, CH, and SH were utilized to produce the fracture loci. Due to the fact that the triaxiality and the Lode angle parameter vary during the deformation, the mean values of these parameters in the entire simulations were regarded to construct the fracture loci. 5. Results and Discussion The fracture loci were produced considering the results of NT5, NT10, NT20, CH, and SH for both VGM and MMC ductile fracture criteria. Subsequently, the FLCs for VGM and MMC criteria were estimated and compared with the experimental findings determined by Banabic (2016). The mean values of stress triaxiality and the Lode angle parameter were attained using Eq. (16) for each specimen's simulation.





1

1

f

f

0 

0 

;

(16)

( ) p    p d



=

( ) p L d

L

=

p  

ave

ave





, p f

, p f