Numerical Simulation of the Thermoforming of an Automotive Dashboard Skin

摘要

The thermoforming process is widely used to create large flat parts such as inner door panels, truck wind deflectors and dashboards. This technique does not require large processing pressure like injection molding; however, the adjustment of local thickness is more difficult as it needs a fine adjustment of the initial temperature of the sheet. For the last decade, numerical simulation involving complex physics such as deforming free surface, contact detection and complex Theological behavior, has been developed to accurately model complex forming processes such as thermofbrming., This paper describes the use of POLYFLOW for computer based modeling to predict the thickness of the thermoformed product. Next, the initial temperature of the sheet is modified; the uneven temperature field leads to different viscosities in each section of the initial sheet, hence a non-uniform resistance to further deformations. This mechanism is used to adjust the final thickness of the product.