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Engineering stress (MPa)
Engineering strain
Figure 2.33 Stress–strain curves of S-2 glass/epoxy at various strain rates (through-
thickness direction) [119]
Tsai and Huang [120] investigated the strain rate effect on the mechanical
behaviours of nylon 6-clay nanocomposites at dry and wet conditions using SHPB.
Dry specimens were controlled by putting the specimens in a vacuum oven at 45 °C,
while the wet specimens were immersed in water for 20 days, 45 °C to accelerate the
moisture absorption. Comparison study was also done between nylon 6-clay with
nylon 6 on the effect of various high strain rate conditions. Results showed that the
strain rate highly influenced the yield stress on the dry nylon 6-clay, but the linear
portion or elastic region of the stress-strain curves is not affected as shown in Figure
2.34. For the wet nylon 6-clay nanocomposites, the stress and strain curves are almost
nonlinear demonstrating significant stiffening behaviours as up to strain rate of 500
-1
s as shown in Figure 2.35.
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