Study on the Heat Transfer Behavior and Warpage Result in Small Quantity of Diverse Molded Part Designs with Varying Thermal Property Mold Insert Control

摘要

The cooling designs always play the most important role in the injection molding process; it is a major part of the total time during injection molding cycle. Therefore, the cooling system will directly affect the molding qualities, but different products shape, ejector pins and other complex mechanism usually restricted the effect of cooling efficiency, which may cause the uneven temperature distribution between core and cavity and leading the warpage issues. In this study, a flash-drive cover mold which has an asymmetric cooling design between cavity and core was used to investigate the wapage under different mold temperature, melt temperature; packing pressure; cooling time and different mold insert material. The two kinds of mold-insert which has different thermal conductivity are implemented for evaluating cooling performance in experiment and numerical approach. The method in profile history variation of mold temperature and maximum temperature differential are established for predicting deflection level. The both experimental and simulated results show that using the high conductivity mold insert (QC-10) can effectively achieve the better uniform temperature between core and cavity that reduce the deformation of 56%. The increasing of mold temperature, packing pressure and cooling time, and the decreasing of the melt temperature can reduce the warpage.