Experimental and Simulation Study on the Warpage of Polyamide 6 Based on Thermo Mechanical Behavior of Material Using Uniaxial Tensile Test

Document Type : Research Article

Authors

Department of Mechanical Engineering, Isfahan University of Technology

Abstract

This research focuses on investigating the time-dependent behavior of polyamide 6 and using the generalized Maxwell model for prediction of this behavior. To achieve this goal, tensile specimens are manufactured via injection molding process and then are tested based on stress relaxation trials. Moreover, two specimens manufactured with different mold temperatures are tested to investigate the effect of the mold temperature on the time-dependent behavior of this kind of polymer. Finally, to evaluate the ability of the generalized Maxwell model to predict the time-dependent behavior of polyamide 6 correctly, a finite element simulation is carried out via a link between the Moldflow and ABAQUS software. In these simulations, the amount of warpage occurring in the specimen obtained from this model is compared with experimental finding. The results show that the mold temperature has a negligible effect on the time-dependent behavior of this polymer and also, there is a good agreement between simulation and experimental results of warpage with a mean error of 13%. Therefore, the generalized Maxwell model is good enough to predict the time-dependent behavior of polyamide 6. On the other hand, this methodology can be used prior to making real parts to prevent the high cost of manufacturing.

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