PSI - Issue 61

Toros Arda Akşen et al. / Procedia Structural Integrity 61 (2024) 260 – 267 Toros Arda Akşen, Bora Şener, Emre Esener, Mehmet Firat / Structural Integrity Procedia 00 (2019) 000 – 000

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fracture model with uniaxial tension test, bulge test was considered. Material’s e xperimental biaxial flow curve was extracted from the study of Yadav (2008).

1000 1200

0 200 400 600 800

Uniaxial Tensile Test Bulge Test

True Stress (MPa)

0 0.1 0.2 0.3 0.4 0.5 0.6

True Strain (-)

Fig. 4. Comparison of true stress-strain curves predicted by uniaxial tension and bulge tests. The computed uniaxial stress-strain curve from model 2 and biaxial flow curve were shown in Fig. 4. The area under the curves were calculated with trapezoidal rule and the value of the critical damage indicator (CDI) was calculated for both tests. The determined values for the CDI were shown in Table 4. The yield function and fracture model were implemented into the Marc through Hypela subroutine.

Table 4. The critical damage indicator values calculated from the different tests. Test ”‹–‹ ƒŽ ሺ ƒሻ Uniaxial tension 182.417 Biaxial bulge 444.416

3. Application The developed numerical model was applied to the fracture prediction of the rectangular cup deep drawing process. The information about the experimental set-up is given in the study (Sener and Kurtaran (2016)). Unlike the study Sener and Kurtaran (2016), the process continued until the fracture occurred. The FE model of the rectangular cup drawing was created in Marc solver. The blank ’s region interacting with the punch radius zone was modeled with the same mesh size as model 2 which is described in Section 2.2; because the critical damage indicator is specified according to the Model 2 and the tearing is expected to occur at the punch radius region of the blank. Fully integrated solid hexahedral elements (Hex7 in Marc) were employed on the mesh layout and four elements through thickness were generated. The FE model of the process is shown in Fig. 5.

Rolling Direction

Fig. 5. Finite element model of rectangular cup deep drawing process