FIBER ORIENTATION MECHANISMS FOR INJECTION-MOLDING OF LONG FIBER COMPOSITES

The development of skin/core fibre orientations in injection molded fibre reinforced compounds is considered, and the applicability of the Tadmor fountain-flow mold filling mechanism to long fibre reinforced is investigated. A disc and plaque mold cavity are used to consider the influence of each injection molding cycle parameter upon the skin/core structure. The influence of the flow path length is also considered. The independent orientation controlling mechanisms identified (the injection speed, melt temperature and the holding pressure cycle all of which influence the fibre orientation favourably) can be used in combination to achieve a optimised microstructure for the cavities under study.