  In this study, we experimentally and numerically investigate the evolution of
the tensile material properties of Discontinuous Fiber Composites (DFCs) with
an increasing average number of platelets through the thickness for two
different platelet widths. The results show that both the number of platelets
and the platelet width have significant effects on the tensile modulus and
strength. We find that not only the average mechanical properties but also
their coefficients of variation change according to the different DFC
mesostructures. To understand the relationship between material morphology at
the mesoscale and corresponding material properties, we developed a random
platelet mesostructure generation algorithm combined with explicit finite
element models. Leveraging the computational tools, we find that moduli and
strength increase with increasing average number of platelets through the
thickness. The increasing trend continues until reaching an asymptotic limit at
about 45 layers through the thickness for the narrow platelets and 27 layers
for the square platelets. In the study, we address the importance of having
accurate simulations of the mesostructure to match not only the average modulus
and strength but also their associated coefficients of variation. We show that
it is possible to accurately predict the tensile material properties of DFCs,
including their B-basis design values. This is a quintessential condition for
the adoption of DFCs in structural applications.
