SPECIAL PRIZE WINNER
Project Name: Why Viscoelasticity Matters: Warpage Prediction of Homopolymers and Short Fiber Reinforced Polymers
School: JKU/Institut für Polymer Product Engineering
By Philipp Stelzer
Warpage prediction is essential to ensuring product quality and complying with specifications of unfilled and short fiber reinforced injection molded polymer components. Therefore, it is necessary to consider the viscoelastic behavior of thermoplastic polymers in order to get accurate simulation results. In this project, Moldex3D was used to investigate the effect of viscoelasticity on the warpage analysis. A methodology for the modeling and simulation of the warpage behavior plus its validation were developed. The validation was performed in a test component and experimental 3D scans. The result showed that having correct characterization and description of the viscoelastic behavior is vital to achieving accurate warpage behavior.
- To develop a methodology for simulating and validating part warpage
- To understand the importance of viscoelasticity in warpage analysis
- To reduce warpage and maintain dimension stability in actual production
Moldex3D was used to carry out the full transient analyses (Ct-F-P-Ct-W) employing the Standard warpage as well as the Enhanced Warpage Solver to predict the warpage behavior. Finally, 3D-Scans utilizing an ATOS Triple Scan III device from GOM GmbH was used to validate the simulation results.
- The warpage results of the point with maximum absolute displacement could be improved by about 520 % for the homopolymer and by about 78 % for the short fiber reinforced polymer employing viscoelastic behavior compared to using the standard warpage solver with elastic models
- Identified the key factors affecting warpage
- Avoided the costly trial-and-error process in mold design via virtual prototyping