Polycarbonate discs were injection molded with different sets of molding conditions.
The parameters studied were the flow rate, melt- and mold-temperature. The
discs were subjected to three point support flexural tests. Those tests are specially
intended for injection molded discs because of their inherent non-flatness. The
through-thickness molecular orientation was assessed by birefringence measurements
along and across the flow direction using the wedge method. This method is
ideal to measure the birefringence of materials that are difficult to cut with a microtome.
The through-thickness stiffness of the discs was calculated from the measured
birefringence distributions. A composite model of the disc was used in the
Algor finite element method (FEW package to simulate the flexural tests
