3-DIMENSIONAL VISCOPLASTIC FEM SIMULATION OF A STRETCH BLOW MOLDING PROCESS

In this study, a viscoplastic FEM simulation of the stretch blow moldi ng process is presented. The material's behavior at elevated temperatu re is assumed to be sh ain-rate-dependent, and a non-Newtonian creepin g material model is employed to specify the strain-rate-sensitive char acteristic of the material. A degenerated quadrilateral shell element, which enables proper evaluation of the bending effect, is employed. T he mold surface is described by triangular surfaces, and the contact p henomenon is modeled as a node-to-mesh contact. In using the code deve loped, the stretch blow molding process is taken as an example and dis cussed qualitatively. First, the process under three boundary conditio ns is simulated and examined, and then the condition leading to the wr inkle phenomenon, which is encountered in the simulation, is discussed . (C) 1998 John Wiley & Sons, Inc. Adv Polym Sci Techn 17: 189-202, 19 98.