STRETCH AND INFLATION OF HYPERELASTIC MEMBRANES AS APPLIED TO BLOW MOLDING

The free and confined inflation of isotropic homogeneous membranes of general shape are considered. The material is assumed to obey the Moon ey-Rivlin constitutive model, and the resulting partial differential e quations, governing the deformation field, are solved using a Galerkin based finite-element procedure. The method is illustrated through exa mples of both free and confined inflation, as well as simultaneous str etch and inflation. Measurements were carried out on the final thickne ss distribution of containers blow-molded in our laboratory. These con tainers typically cover a wide range of geometry and size, including b ottles with handles. Comparison between theory and experiment leads ge nerally to good agreement, despite the limitation of the membrane hypo thesis.