Page 83 - Template Tesis UTM v2.0

studied. It was observed that the capability of energy absorption decreased with

increasing impact load. Moreover, the higher the impact loading imposed on the tested
specimens, the higher the damage area severity recorded as inspected visually. When

tested specimens were imparted with 64 J energy, perforation as a dominant damage
was occurred in addition to fibre breakage, matrix cracking and delamination [97].

Hemp/glass fibre hybrid bio-composites was impacted with 4 J impact energy

and the study revealed that the hybrid composites lost only about 30% of their intrinsic
strength and stiffness, compared to 70% loss for hemp fibre composites at same impact

energy [20].

Hosur et al. [98] experimentally investigated the low velocity impact response

of woven hybrid composites at four different combinations between twill weave
carbon fabric and plain weave S2-glass toughened epoxy. Tested specimens were

imparted at four different energy levels of 10, 20, 30 and 40 J. Results showed that the
hybrid specimens recorded an improvement in the load carrying capability in

comparison with carbon/epoxy. It was observed that carbon/epoxy was failed through

partial penetration and back face splitting. Hybrid composite of carbon/glass with S2-
glass layer at the back surface was able to enhance the impact strength due to higher

strain to failure of glass fibre. Maximum load, maximum energy, maximum absorbed

energy and maximum deflection increase with increasing impact energy for all the
laminates, except carbon/epoxy.

Impact properties and life cycle assessment were investigated between woven
jute and glass fabrics toughened epoxy composite. It was found that the glass woven

composites at the outer surface of the sandwich can act as strong skins. The bending
and impact (drop weight) properties of jute–glass woven composites are higher than

those of jute woven composites. Jute/epoxy exhibited a complete penetration of impact

failure with the impactor stuck in the laminate. Fibre failure and matrix cracks were
clearly observed at the back surface with circular hole impact damage that indicated

the nearly quasi-isotropic properties of the laminate (such as tensile strength is
dominant at main direction of 0 and 90°) as illustrated in Figure 2.26. However,

jute/glass exhibited non-perforated impact damage with impactor bounce back. The

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