This paper describes a computational model for the warpage analysis of injection molded short-fiber-reinforced thermoplastics. In the analysis, the molded part's warpage is predicted from the calculated fiber orientation, the volumetric shrinkage, and the thermo-mechanical properties of the fiber and the polymer. Results for a real injection molded part are presented to demonstrate the application of the method. Predicted warpage results are in good agreement with experimental observations. The analysis allows isolation of the cause of warpage, and the fiber orientation effect was found to be dominant.
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