3-DIMENSIONAL FINITE-ELEMENT SIMULATION OF THERMOFORMING

The development of a finite element program specifically designed to simulate thermoforming in complex three‐dimensional geometries is described. The large strain finite element model developed for simulating thermoforming processes is based on a total Lagrangian formulation which results in a nonlinear system of equations that must be solved iteratively. The nonlinear material behavior and contact between the polymer and mold surf aces ieads to additional complications in the numerical solution of the thermoforming simulation problem. In an effort to verify the accuracy of the finite element model developed in this study, analyses are compared with measurements obtained from three‐dimensional three‐formed parts. Copyright © 1990 Society of Plastics Engineers