Minimization of warpage and sink index in injection-molded thermoplastic parts using Taguchi optimization method

The objective of this paper consist of minimization of the warpage and sink index in terms of process parameters of the plastic parts have different rib cross-section types, and rib layout angle using Taguchi optimization method. Considering the process parameters such as mold temperature, melt temperature, packing pressure, in addition to rib cross-section types, and rib layout angle, a series of mold analyses are performed to exploite the warpage and sink index data. The polymeric materials were selected PC/ABS, POM, and PA66. Taguchi optimization method was used by exploiting mold analyses based on three level factorial design. Orthogonal arrays of Taguchi, the signal-to-noise (S/N) ratio, the analysis of variance (ANOVA) are utilized to find the optimal levels and the effect of process parameters on warpage and sink index. Confirmation analysis test with the optimal levels of process parameters are carried out in order to demonstrate the goodness of Taguchi method. From this, it can be concluded that Taguchi method is very suitable to solve the quality problem occurring the injection-molded thermoplastic parts. (C) 2005 Elsevier Ltd. All rights reserved.