Dynamic mold temperature control enables to mold micro structures and provides major improvements regarding surface quality. Weld line marks can be significantly reduced, gloss and matte finishes appear more intense [1,2]. Fluid-based temperature control is a common technique for dynamic temperature control. Two temperature control units are operated at different temperatures. Prior to injection, the mold is heated above melting or glass transition temperature. After injection and packing, solidification is performed by switching to the cold temperature control unit [1]. As a complete mold or mold inserts are heated and cooled in each cycle, fluid-based dynamic temperature control leads to high cycle times and energy consumption [2]. These are considerable economic barriers, beside investment costs for temperature control systems. Based on an appropriate thermal design of a mold, process economics can be improved by optimized heat transfer within that mold. For optimization, convective heat transfer within tempering channels and thermal conductivity of molds are promising factors. Therefore, injection molding experiments were performed evaluating cycle time, energy consumption and cavity wall temperature. It could be observed that enhanced heat transfer within molds, offers significantly reduced cycle times and energy consumption.

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