We assess the strength of injection-molded parts with respect to filler orientation, weld lines, and voids. We include the viscoelastic behavior of plastics. We verify the mechanical performance of plastic parts and injection molds under load.

The injection molding process and the associated technological design of the part can significantly affect the strength of the plastic part. The presence of weld lines and voids can have a major impact on its mechanical behavior. During the mold cavity filling, orientation of the supramolecular structure and potentially fibrous filler occurs. Throughout the injection process, residual stresses are induced in the plastic part due to internal forces. The strength of the molded plastic part also depends on the value and duration of the packing phase. The mechanical behavior is further influenced by mold temperature and the temperature field during the cycle. These inhomogeneities can be very well predicted using CAE Moldflow analysis.

To make the structural analysis as realistic as possible, we include the inhomogeneities that arise during the injection process in the calculation. That means fiber orientation, weld lines, residual stresses, and to some extent also voids and crystalline structure orientation. The analytical task is then solved as a combination of Moldflow simulation and structural analysis.