Page 77 - Template Tesis UTM v2.0

±45, 0/90, Core, 0/90, 0/90, 0/90, 0/90], respectively. From Figure 2.21, it can be

observed that SC2 exhibited the higher peak load and lower displacement in
comparison with SC1. In addition, it can be concluded that SC1 specimens exhibited

a brittle behaviour due to small energy required to initiate a crack until complete
penetration which opposed SC2 that shows a ductile behaviour as elucidated on the

slope of the load - displacement curve. The important parameters which highly
influenced on the quasi static responses of the tested specimens as discovered in this

study [82] are fibre orientation, reinforcement performance, amount of materials used

and number of plies

Figure 2.21 Load - displacement curves for quasi-static test of carbon sandwich
composites [82]

S2/SC-15 glass/epoxy composite was quasi-statically indented between 1.2 to
50 mm/min to the target displacement of 6.08 mm to find the average of peak energy.

As a result, peak energy of 30.7 J was obtained from the total of 25 tested specimens.

This peak energy will be imposed during subsequent of low velocity impact test on the
identical specimen as used in quasi-static test. It was observed that delamination areas

and permanent dent exhibited by the quasi-static’s specimens were larger than low

velocity impact’s specimens as illustrated in Figure 2.22. Only interlaminar fracture
(horizontal cracks between layers) was significantly observed for the material tested

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