Issue 67

S. Verenkar et alii, Frattura ed Integrità Strutturale, 67 (2024) 163-175; DOI: 10.3221/IGF-ESIS.67.12

Upon stacking the initial four layers of fabric, a deliberate step was taken to introduce delamination. This was achieved by placing a 40 x 40mm Teflon film at the centre of the laminate, as illustrated in Fig. 1. Special care was taken during the casting process to ensure the proper formation of the delamination. Subsequently, additional layers of fabric were added according to the prescribed stacking sequence in order to complete the laminate structure. Post-stacking, the composite laminate underwent a curing process under atmospheric conditions for a duration of 24 hours. Material properties for the composite laminate were evaluated using the rule of mixtures [17] and are summarized in Tab. 1.

Figure 1: Stacking sequence and interface region in Glass-epoxy composite plate.

Material Properties

Values

E 11

39.51 GPa 6.38 Gpa 2.47 GPa 2.73 GPa

E 12= E 13 G 12 =G 13

G 23

ν 12=13

0.28

ρ 1900 kg/m 3 Table 1: Properties of Glass-Epoxy composite plate.

b

Delamination

a

Figure 2: Composite plate of dimensions 250mm x 250 mm x 1.2mm.

165