On the effect of the fiber orientation on the flexural stiffness of injection molded short fiber reinforced polycarbonate plates

摘要

The through-thickness fiber orientation distribution of injection molded polycarbonateplates was experimentally determined by light reflection microscopy andmanual digitization of polished cross sections. Fiber length distribution was determinedby pyrolysis tests followed by image analysis. A statistical analysis was doneto determine the confidence limits of the fiber orientation results. The fiber orientationdistribution was described by using second-order orientation tensors. The throughthicknessstiffness variations were determined by the orientation averaging approach.This layer stiffness distribution was used to simulate the behavior of beams subjectedto three point bending with a FEM Ansys model. The results were comparedwith experimentally determined flexural stiffness both in the flow direction and in thetransverse flow direction. The effect of flow rate and melt-temperature on stiffnessand fiber orientation is discussed.