Integration optimization of molding and service for injection-molded product

Different settings of process parameters in injection molding can directly influence the internal residual stress of injection parts, while to a certain degree, the internal residual stress field will, in turn, affect the performance of parts during assembly and service process. Therefore, for most parts which will be subjected to external loads as part of a system, it has practical significance to improve their performance through integration optimization of molding and service. In this paper, the service of a molded part is divided into three stages: molding, assembly, and service, and an integration model is built for optimizing its service performance, considering all these three stages. A sequential optimization algorithm based on kriging surrogate model and expected improvement sampling criteria is used to perform the optimization analysis on polycarbonate material parts. Results show that the integration optimization strategy proposed in this paper can decrease the maximum service stress effectively. Furthermore, the non-assembly and non-load carrying parts are also considered and the stresses are optimized. Comparison among these three situations shows that integration optimization is essential when service performance is considered for the molded parts.