High precision validation of micro injection molding process simulations

Abstract

Simulation of the micro injection molding (μIM) process is a powerful tool to perform product, tool and process design in the early stages of the development of polymer micro components. However, the necessary precision needed to exploit the advantages of process simulation is challenging the software simulation technology. High accuracy μIM process control is a key aspect when performing micro molding simulations. Hence, data analysis and simulations of μIM experiments have been conducted. Micro molding simulations have been executed by implementing in the software the actual processing conditions.Various aspects of the simulation set-up have been considered in order to improve the simulation accuracy (i.e. to decrease deviations from experimental values): injection speed profile, pressure at injection location, melt and mold temperatures, three-dimensional mesh parameters, and material rheological characterization. Quality factors investigated for the quantitative comparisons were: short shot length, injection pressure profile, molding mass and flow pattern.Inconsistencies and uncertainties in the experimental data must be minimized to avoid introducing uncertainties in the simulation calculations. In this work, simulations of bulky sub-100 mg micro molded parts have been validated. A methodology for accurate micro molding simulations is proposed and established.