Page 79 - Template Tesis UTM v2.0

Indentation test was done on the carbon/epoxy with different thickness and ply

orientation to form the contact law by using the method of least squares. From
experimental test, it can be concluded that laminate thickness significantly influenced

the deflection of the tested specimens. Thicker specimen exhibited less deflection
instead of larger deflection was observed on the thinner specimens [94].

Zhu et al. [95] investigated the quasi-static indentation test of carbon/glass

reinforced epoxy at different loading conditions of 0°, 45° and 90°. Compression
strength and modulus at 0°, 45° and 90° were 301.92, 125.52, 269.46 MPa and 6.67,

2.97, 6.62 GPa, respectively. Tested specimens showed a brittle failure, particularly at
axial directions (0° and 90°). Initial elastic deformation was recorded on the stress-

strain curves followed by nonlinear performance until complete failure.

Hachemane et al. [46] experimentally investiagted the jute/epoxy-cork

sandwich on indentation test to evaluate the influence of cork density on the damage
behaviour of sandwich composite. It was found that the cork density influenced the

damage force, maximum force and damage size. Two corks with different densities

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were used in this study, namely 310 and 160 kg/m . Results indicated that the sandwich
panel with heavy agglomerated of higher cork density exhibited a weaker energy

dissipation capacity which was 3.29 % lower than lighter cork.

2.14 Impact Response of Fibre Reinforced Polymer Composites

Low velocity impact test was conducted on S2/SC-15 glass/epoxy composite

to compare the response of the tested specimen with quasi-static indentation. Peak
energy of 30.7 J which was obtained from quasi-static indentation was applied in the

impact test. Low velocity impact was done at velocity 3.41 m/s. The results showed

that the tested specimen exhibited higher initial stiffness and energy absorption
capacity in comparison with quasi static indentations’ specimens. Contrary, maximum

force and displacement values were exhibited slightly higher in comparison with quasi
static indentation test of identical specimen. Significant intralaminar fracture (vertical

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