In the conventional injection molding process a constant temperature of the mold is required depending on the type of injected polymer. Cooling process usually takes 2/3 of the entire production cycle time, so reduction of cooling time should lead to the decrease of the manufacturing cost. In practice, lower mold temperature can lead to the occurrence of the unwanted defects. The most common defects include short shots, diesel effect, visible weld lines, excessive internal stresses and warp. Those defects are more common and evident when injected parts are fitted with thin elastic hinges, where flow of the molten polymer through the very narrow channels causes the shear of polymer chains. In this work, a concept and simulative studies of selectively heated injection molds are presented. The idea of the novel technology is to heat only certain regions of the cavity where molten polymer cools down rapidly or where cavity cross-section is very narrow. It can be achieved with induction heating technology. The results showed that apart from the hinge geometry, the forming temperatures played an important role in shearing of polymer chains. The changes of analyzed parameters also influenced how material filled the cavity.

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