Optimization of material and process parameters in the injection molding of piezoresistive card-type pressure sensors using the finite element method

The purpose of this study is to determine the most suitable material and process parameters for piezoresistive card-type pressure sensors during the injection molding process. Simulation analyzes done with different engineering plastics Polyamide (PA), Polybutylene Terephthalate (PBT) and Polycarbonate (PC) focus on the optimization of critical parameters such as fill time, injection pressure, volumetric shrinkage and cooling efficiency during the production process. Cooling channel diameter was 10 mm, cooling water temperature was 25°C and Reynolds number was 10,000 designed to provide the minimum time of delivery from the mold by using idle times. Results indicate that PA has the shortest filling time of 0.0548 sec, PC has a volume shrinkage of 6.63%, among the lowest ones and PBT shows the best thermal stability of 252.8°C PA, which operates at lower injection pressure (132.3 MPa), increases throughput, while PBT has exhibited a proper balance between mechanical and thermal performance and PC is the most suitable material for high-dimensional accuracy applications. This study serves as a guide for optimizing the material selection and molding parameters in the production of plastic-based pressure sensors.