As can be seen in the figure, the axial modulus
reduction rate of the material is very sensitive to the load level and number of cycles.
The axial modulus
is not sensitive to the arrangement of the ZnO nanowires, and the predictions from EMT-based approach match the values predicted using the FEM.
The existing research results of GFRP mechanical properties in multi-axial stress state are mainly concerning the axial modulus, the strength, and the failure mode, but there are few research results concerning the other aspects of mechanical properties (such as transverse modulus, Poisson ratio).
The axial modulus [E.sub.1] and the transverse modulus [E.sub.2]:
In addition, the nanoindentation predominantly measures transverse modulus along the radial direction in the fibers while the tensile tests are a measure of the axial modulus
. In studies of indentation modulus of zinc single crystals, Vlassak and Nix (16) show that the indentation modulus does change with orientation but changes less than the true modulus as the orientation goes from the hexagonal axis to the basal plane.
[m.sub.a] is the axial modulus
of the worm gearing;
Typically, as shown in the figure, for uniaxial tension the axial modulus
increases and the transverse modulus decreases with the increase of plastic strain.
the reduced axial modulus
, for the corresponding uniaxially oriented composite, and [E.sub.11]/[E.sub.0] for [alpha] = 150; [alpha] = 150 accounted better for the data for the fibers at low MMT contents, consistent with the significant increase in [alpha] on fiber drawing implied by morphological data, although it should be borne in mind that the MMT particles, and in particular the sheared stacks are not equivalent to monolithic particles with an axial modulus
equal to that of an individual platelet.
Continuous fiber composite micromechanics for axial modulus
is known to follow the rule of mixtures  derived from the assumption of constant strain in the constituents.
With this range of draw ratio for PET, the axial modulus determined by ultrasonics increases almost linearly from 4 to 16 GPa while the transverse modulus is almost constant near 4 GPa.
For the axial modulus, the deviation increases progressively with the draw ratio from 20% to 60% while the transverse modulus remains roughly constant around 15%.