The development of an effective and representative finite element-based simulation of the deep-draw plug-assisted thermoforming process is presented. It has been clearly demonstrated that the frictional and thermal effects of plug contact are of critical importance and appropriate relationships for these have been developed and included in the simulation. A constitutive material model based on the van der Waals strain energy function has been used to represent the deformation response of the high-impact polystyrene polymer sheet and the model parameters have been closely fitted to biaxial test data. The prototype simulation is stable and its output is generally in good agreement with experimental measurements. It is recognized that model accuracy could be improved further through additional experimental investigation of the process. The working simulation provides a powerful platform for in-depth analysis of the thermoforming process.
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