0

Full Content is available to subscribers

Subscribe/Learn More  >

Determination of Pressure in the Mold Cavity of Injected Semi-Crystalline Thermoplastics

[+] Author Affiliations
Xavier Tardif, Vincent Sobotka, Nicolas Boyard, Didier Delaunay

Nantes University, Nantes, France

Philippe Le Bot

Plastic Omnium Auto Exterior - SIGMATECH, Sainte Julie, France

Paper No. ESDA2012-82134, pp. 611-618; 8 pages
doi:10.1115/ESDA2012-82134
From:
  • ASME 2012 11th Biennial Conference on Engineering Systems Design and Analysis
  • Volume 2: Applied Fluid Mechanics; Electromechanical Systems and Mechatronics; Advanced Energy Systems; Thermal Engineering; Human Factors and Cognitive Engineering
  • Nantes, France, July 2–4, 2012
  • Conference Sponsors: International
  • ISBN: 978-0-7918-4485-4
  • Copyright © 2012 by ASME

abstract

Injection molding is the most used process for thermoplastic part manufacturing. This process is commonly divided into four steps: injection, packing, cooling and ejection. During the packing step, an amount of material gets into the mold cavity to compensate for shrinkage of the polymer mainly due to the crystallization. Once the gate is frozen, polymer is subjected to isochoric cooling while the pressure of the polymer is higher than atmospheric pressure. Improving the quality of the injected part requires prediction of the shrinkage, warpage and residual stress and pressure impacts deeply on the morphology and consequently on the shape of the final part. The pressure decrease during the isochoric phase also determines the ejection time. However, description of the behavior of the polymer during packing and isochoric steps needs an accurate model that considers coupling between heat transfer and crystallization and also a good knowledge of the behavior (specific volume and crystallization kinetics) of the polymer under high pressure. Some studies have already underlined the influence of shear rate on the kinetics of crystallization. Here, based on a pressure analysis and an experimental-numerical comparison, we confirm crystallization is strongly coupled to flow history.

Copyright © 2012 by ASME
Topics: Pressure , Cavities

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In