Caractérisation viscoélastique du comportement d'une membrane thermoplastique et modélisation numérique de thermoformage |
| |
Authors: | F Erchiqui A Imad A Mouloudi F Slaoui Hsnaoui |
| |
Affiliation: | 1. Université du Québec en Abitibi‐Témiscamingue, 445, boul. de l'Université, Rouyn‐Noranda (Québec), Canada, J9X 5E4;2. Laboratoire de Mécanique de Lille (UMR CNRS 8107), Université de Lille1 Polytech'Lille, Avenue Paul Langevin, 59655 Villeneuve d'Ascq, France |
| |
Abstract: | In this work, we are interested, on the one hand in the characterization of circular polymeric ABS membrane under biaxial deformation using the bubble inflation technique, on the other hand in modelling and numerical simulation of the thermoforming of ABS materials using the dynamic finite element method. The viscoelastic behaviour of the Lodge model is considered. First, the governing equations for the inflation of a flat circular membrane are solved using a variable‐step‐size‐finite difference method and a modified Levenberg‐Marquardt algorithm to minimize the difference between the calculated and measured inflation pressure. This will determine the material constants embedded within the model used. For dynamic finite elements method, we consider a nonlinear load in air flow which obeys the Redlich‐Kwong equation of state of the real gases. For numerical simulation, the lagrangian formulation together with the assumption of the membrane theory is used. Moreover, the influence of the viscoelastic model on the thickness and on the stress distribution in the thermoforming sheet are analysed for ABS material. |
| |
Keywords: | viscoé lastique ABS é lé ments finis caracté risation biaxiale gaz ré el é quation d'é tat de Redlich‐Kwong thermoformage viscoelasticity ABS finite element biaxial characterization real gas Redlich‐Kwong equation of state thermoforming |
|
|