Effect of rapid temperature variations on the resulting orientation and morphology of micro molded parts

The micro-injection molding is a promising technology for the production of micro-components. The potentiality of the process can enhance by adopting an efficient temperature control of the cavity surface. The advantages of this system are linked to the increase of the polymer flowability and thus the complete filling of thin cavity. In this work, a rapid surface heating/cooling was adopted in a cavity for the micro-injection molding. Electrical resistive thin components were used for the heating by the Joule effect. The system is able to increase the mold surface temperature of one hundred of°C degrees in a few seconds and to control the temperature during the injection. Experiments were carried out by using a biodegradable polymer, the PLA, in order to check the effect of rapid temperature variations of the cavity surfaces on the final flow length and the morphology of the micro-parts.