A novel method for determining the pressure dependent characteristics of polymer melt during micro injection molding

Junjie Liu; Baishun Zhao; Dimitrios Kontziampasis; Bingyan Jiang; Wangqing Wu

Polymer Testing (Aug 2024)

A novel method for determining the pressure dependent characteristics of polymer melt during micro injection molding

Junjie Liu,
Baishun Zhao,
Dimitrios Kontziampasis,
Bingyan Jiang,
Wangqing Wu

Affiliations

Junjie Liu: State Key Laboratory of Precision Manufacturing for Extreme Service Performance, School of Mechanical and Electrical Engineering, Central South University, 410083, Changsha, China
Baishun Zhao: State Key Laboratory of Precision Manufacturing for Extreme Service Performance, School of Mechanical and Electrical Engineering, Central South University, 410083, Changsha, China
Dimitrios Kontziampasis: Department of Mechanical and Industrial Engineering, School of Science and Engineering, University of Dundee, DD1 4HN, Dundee, Scotland, UK; Dundee International Institute of Central South University, Central South University, 410083, Changsha, China; School of Mechanical Engineering, Faculty of Science and Engineering, The University of Leeds, Leeds, Yorkshire, LS2 9JT, UK
Bingyan Jiang: State Key Laboratory of Precision Manufacturing for Extreme Service Performance, School of Mechanical and Electrical Engineering, Central South University, 410083, Changsha, China
Wangqing Wu: State Key Laboratory of Precision Manufacturing for Extreme Service Performance, School of Mechanical and Electrical Engineering, Central South University, 410083, Changsha, China; Dundee International Institute of Central South University, Central South University, 410083, Changsha, China; Corresponding author. State Key Laboratory of Precision Manufacturing for Extreme Service Performance, School of Mechanical and Electrical Engineering, Central South University, 410083, Changsha, China.

Journal volume & issue: Vol. 137
p. 108520

Abstract

Read online

Micro injection molding is used to manufacture thin-walled parts with micron-scale structures. wherein high shear rate and high injection pressure process conditions appear. Consequently, the pressure dependence of polymer melt viscosity at the microscale cannot be ignored. However, in the simulation analysis of the microinjection molding process, almost all the Cross-WLF models of polymeric materials are omitting the pressure dependence parameter D3. This has a huge impact on the accuracy of the simulation results. Herein, a method that combines experimental characterization and filling simulation is proposed for the determination of the pressure dependence of polymer melts during micro injection molding. D3 in the Cross-WLF model of Polymethyl methacrylate (PMMA) and Cycloolefin copolymer (COC) is characterized by capillary rheometer and counter pressure chamber. The developed viscosity model including D3 is used for a filling simulation and is compared with the experimental results. The model flow simulation results showcases that the prediction accuracy of the viscosity model is significantly improved after considering D3. These results are of great significance, as they can be used to reduce the development cost and to improve the simulation accuracy of the micro injection molding filling process.

Published in Polymer Testing

ISSN: 0142-9418 (Print); 1873-2348 (Online)
Publisher: Elsevier
Country of publisher: United Kingdom
LCC subjects: Technology: Chemical technology: Polymers and polymer manufacture
Website: https://www.journals.elsevier.com/polymer-testing

About the journal

Abstract

Keywords