Optimizing the plastic injection molding process and reducing warpage through response surface methodology

Warpage is a discomfort defect that stays on the plastic product during injection molding process (IMP). This paper demonstrates a method to reduce warpage during IMP by using a response surface methodology (RSM). Five key processing parameters are variables in the fitting function generated from RSM. Moldex3D software is the effective tool for designing IMP and analyzing defects such as warpage and shrinkage. The material is a general purpose polystyrene. The warpage prediction model, significant influencing factors, and optimization have been found. The results show that the prediction warpage is 0.834 mm corresponding to warpage reduction of 3.25% via using RSM method. The optimal value has recorded with 0.846 mm corresponding to warpage decrease of 1.86%. The technique is crucial for designing and setting the press parameters in actual IMP. The paper hopes that the results will encourage application of the method in real production to reduce fails and improve product quality.