Page 174 - Template Tesis UTM v2.0
P. 174
The ratio of impedance ( ) is given by Equation 4.5;
= x 100 (4.5)
Where;
- mechanical impedance value of tested specimen
- mechanical impedance value of silver steel bar
Table 4.8 shows the summary of wave velocity, impedance and impedance
ratio for hybrid and pure composites. The same method was practiced in determining
the function of filler loading for sawdust/HDPE specimens under various strain rates
[169]. Hybrid composites of E-glass/basalt, E-glass/jute and E-glass/flax exhibit
higher wave velocity and mechanical impedance value in comparison with their pure
laminates of natural fibres. Table 4.9 summarised the maximum stress, strain at
maximum stress and dynamic stiffness for hybrid composites of E-glass/basalt, E-
glass/jute and E-glass/flax obtained from SHPB test. The recorded data was
determined with the assumptions as mention by Cronin et al. [103], where the
deformation of the specimens was uniform during the test, inertial and frictional effects
were neglected, and the bars were overwhelmed the specimen’s size.
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