A METHOD FOR CONTROLLING THE MOLD FILLING VOLUME FOR BMC INJECTION MOLDING

摘要

Bulk molding compound (BMC) compositions are characterized by a comprehensive property profile, which makes this thermoset material attractive for a wide range of high-performance applications. BMC processing by injection molding allows high production rates and the fabrication of parts with a considerable shape complexity [1]. Although the injection molding machine offers a high reproducibility and process reliability [2], several effects such as material induced disturbances or changing ambient conditions may cause fluctuations in BMC injection molding. The result is a varying part quality for example in the form of volumetric filling differences which causes rejects. The manual adaption of certain process setting parameters presents a possibility to react on disturbances in order to achieve constant part properties. However, the outcome of these adjustments is dependent on the experience of the operator, since an accurate knowledge of the influence of certain setting parameters on individual part quality features is required [3]. In this paper a correlation between process setting parameters and the part filling volume for BMC injection molding is introduced and discussed. The main aim is the development of an adaptive machine function which autonomously compensates occurring disturbances and ensures a constant part filling in BMC injection molding.