PSI - Issue 52

Satrio Wicaksono et al. / Procedia Structural Integrity 52 (2024) 438–454 Satrio Wicaksono et al./ Structural Integrity Procedia 00 (2023) 000 – 000

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Table 9 Effect of plastic area parameter to the failure visualization of T-joint structure.

Crippling

Buckling

Strain hardening slope

Failure visualization

The red dot in Figure 12 is the point where the vertical sandwich begins to experience crippling. Based on Figure 12, it can also be concluded that the material with crippling failure (black line) has a lower gradient after passing through the red point. This means that to make the impactor detach from the joint, that is, when the kinetic energy reaches 0 J, model with crippling failure mode takes longer time than model with buckling failure mode. In the buckling failure mode the model is more difficult to deform so that it can withstand the impactor up to 0 J more quickly. Strain hardening slope is a very critical material properties, as it directly affect the failure mode of the T joint.

Kinetic Energy [J]

Time [ms]

Figure 12 Effect of plastic area parameter to the kinetic energy history plot of AL1050-H14.

4. Conclusions The finite element modelling of the failure of T-joint foam-core sandwich composite structures was carried out. The foam was modeled using crushable foam model combined with ductile damage model while the delamination between the skin and the foam was modeled using bilinear cohesive elements. The prediction from the numerical simulation has been validated against experimental results from the literature, which shows that the constructed numerical model has been able to capture the failure morphology such as delamination, core shearing, and core crushing damages similar to the experimental result. Additionally, the numerical results capable to predict the