PSI - Issue 37

Md Niamul Islam et al. / Procedia Structural Integrity 37 (2022) 217–224 Md Niamul Islam et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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storage modulus ranged between 4500 MPa and 6000 MPa and the loss modulus varied between 300 MPa and 500 MPa. The average value tan delta of the material in this frequency range was 0.08. The low value indicated that the polymer composite material exhibited a rather high elastic behaviour.

Fig. 6. Failure of specimens in tensile (a) and compression (b) tests.

6200

480

0.11

Storage Modulus (MPa) Loss Modulus (MPa) Tan delta

6000

460

0.10

5800

5600

440

0.09

5400

5200

420

0.08

5000

400

0.07

4800

4600

380

0.06

0

20

40

60

80 100 120 140 160

Frequency (Hz)

Fig. 7. Storage modulus, loss modulus and tan delta of Nylon SCF for frequency sweep at 25 °C.

Fig. 8. AM solid plates of Nylon SCF tested at 100 m s -1 ballistic impact: (a) front side; (b) back side.

Further, the front and back sides of the tested plate under ballistic impact are shown in Fig. 8. All 5 plates tested exhibited similar fracture character with complete penetration. The front side of the plate showed localised fracture, exhibiting a rough circular hole (Fig. 8a, denoted with a white circle). On the other hand, the back side of the plate