ON THE EFFECT OF THE FIBER ORIENTATION ON THE FLEXURAL STIFFNESS OF INJECTION-MOLDED SHORT-FIBER-REINFORCED POLYCARBONATE PLATES

The through-thickness fiber orientation distribution of injection mold ed polycarbonate plates was experimentally determined by light reflect ion microscopy and manual digitization of polished cross sections, Fib er length distribution was determined by pyrolysis tests followed by i mage analysis. A statistical analysis was done to determine the confid ence limits of the fiber orientation results. The fiber orientation di stribution was described by using second-order orientation tensors. Th e through-thickness stiffness variations were determined by the orient ation averaging approach. This layer stiffness distribution was used t o simulate the behavior of beams subjected to three point bending with a FEM Ansys model. The results were compared with experimentally dete rmined flexural stiffness both in the flow direction and in the transv erse flow direction. The effect of flow rate and melt-temperature on s tiffness and fiber orientation is discussed.