Dynamic Mold Surface Temperature Control Using Induction and Heater Heating Combined with Coolant Cooling

Abstract In this study, both electrical heater heating and electromagnetic induction heating combined with coolant cooling are developed to achieve a dynamic mold surface temperature control. Simulation tool was also developed by integration of both thermal and electromagnetic analysis modules of ANSYS. The capability and accuracy of simulations on the heater heating and induction heating were verified with experiments. To evaluate the feasibility and efficiency of heater heating and induction heating on the mold surface temperature control, a mold plate, roughly about an inset size of cellular phone housing, installed with five heaters and designed with four cooling channel with coolant running through, was utilized for the demo experiments varying mold surface temperature between 110 °C and 200 °C. During induction heating/cooling case, it takes 4 s to increase mold surface temperature from 110 to 200 °C and it takes another 21 s for mold surface to cool down to 110 °C. The mold plate surface temperature can be raised at about 22.5 °C/s and cooled down at 4.3 °C/s within the mentioned temperature range. Mold plate temperature distribution exhibits good uniformity as well in all stage of heating/cooling process. For heaters heating, it takes 37 s to increase mold surface temperature from 110 to 200 °C and it takes another 30 s for mold surface to cool down to 110 °C. The temperature rising rate is only about 2.4 ° C/s. Induction heating is more efficient in mold surface temperatures control than electrical heating and it does eliminate the weld line mark when applied to a tensile test mold with double gate design prior to melt injection.