PSI - Issue 42

791 7

Md Niamul Islam et al. / Procedia Structural Integrity 42 (2022) 785–792 Md Niamul Islam et al. / Structural Integrity Procedia 00 (2019) 000–000

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Fig. 7. AM nylon CCF solid plates tested in ballistic impact at 100 m s -1 : (a) front side; (b) back side.

The obtained numerical results for the nylon CCF plate after ballistic impact at 100 m s -1 with a spherical projectile are shown in Fig. 8. Complete perforation was achieved, with a circular damaged area at the front (Fig. 8a) and delamination failure at the back (Fig. 8b), similar to the experimental results. In comparison to the model of nylon SCF in Islam et al. (2021), the front damaged area was considerably lower (16%) due to higher structural stiffness, and the back damage area was substantially lower (61%) due to the implementation of the cohesive surface. For nylon CCF, the damaged areas between the experiment and numerical model showed a reasonable agreement (differences of 4% at the front and 11% at the back) for ballistic impact.

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Fig. 8. Numerical results for von Mises stress in ballistic impact at 100 m s -1 : (a) front side; (b) back side; (c) side view.

Table 4. Damaged areas for nylon SCF from Islam et al. (2021) and nylon CCF (Figs. 7 and 8). Parameter Nylon SCF – Experiment Nylon SCF – Model Nylon CCF – Experiment Nylon CCF – Model Front damaged area (cm 2 ) 1.64 1.30 1.05 1.09 Back damaged area (cm 2 ) 7.44 9.75 3.39 3.76