Skip to content
Licensed Unlicensed Requires Authentication Published by De Gruyter April 6, 2013

Study on Mold Filling Behaviors of Micro Channels in Injection Molding

  • J.-H. Li and W.-B. Young


Computational simulation model has been used extensively in studying the filling flow in injection molding process. Most of the models are based on the assumption of a no-slip boundary condition and are verified by the experiments of filing flow in macro scale. This study is to investigate the flow behaviors during the micro channel filling of an injection molding process. Flow distances were measured on products from series of short shots to understand the relationship between the injection pressure and flow distance. It was found that cavity size variation due to mold deformation is important in the micro injection molding. By adjusting the cavity size due to mold deformation, the C-Mold simulation provides reasonable results compared to the experimental data for cavity thickness in 150 μm or 200 μm. On the other hand, the simulation will not give accurate prediction of filling flow for a micro cavity that has a depth below 100 μm. The wall slip effect is believed to the major reason and must be considered in the analysis for a cavity size below 100 μm.

Mail address: Wen-Bin Young, Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan, Taiwan, R.O.C. E-mail:


Becker, E. C., et al., “Fabrication of Microstructures with High Aspect Ratios and Great Structural Heights by Synchrotron Radiation Lithography, Galvanoforming, and Plastic Moulding (LIGA Process)”, J. Micromech. Microeng., 4, 3556(1986)Search in Google Scholar

Chang, H. C., Young, W.-B., “Experimental Study on the Filling of a Micro Injection Molding with Cylindrical Dot Patterns”, International Polymer Processing, 2005. 20(3): p. 245249(2005)10.3139/217.1884Search in Google Scholar

Cheng, Y., et al., “Ultra-deep LIGA Process”, J. Micromech. Microeng., 9, 5863(1999) DOI: 10.1088/0960-1317/9/1/307Search in Google Scholar

Despa, M. S., et al., “Injection Molding of Polymeric LIGA HARMs”, Microsystem Technologies, 2, 6066(1999)10.1007/s005420050176Search in Google Scholar

Kim, D. S., et al., “Micro-channel Filling Flow Considering Surface Tension Effect”, J. Micromech. Microeng., 3, 236246(2002) DOI: 10.1088/0960-1317/12/3/307Search in Google Scholar

Madou, M. J., et al., “Design and Fabrication of CD-like Microfluidic Platforms for Diagnostics: Microfluidic Functions, Biomedical Microdevices, 3, 245254(2001)10.1023/A:1011419515576Search in Google Scholar

Piotter, V., et al., “Performance and Simulation of Thermoplastic Micro Injection Molding”, Microsyst. Technol., 6, 387390(2002) DOI: 10.1007/s00542-002-0178-6Search in Google Scholar

Yang, S. P., Young, W.-B., “Microinjection Molding with LIGA-Like Process”, Int. Polym. Process., 2, 180185(2004)Search in Google Scholar

Yao, D. G., Kim, B., “Simulation of the Filling Process in Micro Channels for Polymeric Materials”, J. Micromech. Microeng., 5, 604610(2002) DOI: 10.1088/0960-1317/12/5/314Search in Google Scholar

Young, W.-B., “Filling and Postfilling Analysis of Injection/Compression Molding”, Int. Polym. Process., 4, 416422(2000)Search in Google Scholar

Yu, L. Y., et al., “Experimental Investigation and Numerical Simulation of Injection Molding with Micro-features”, Polym. Eng. Sci., 5, 871888(2002) DOI: 10.1002/pen.10998Search in Google Scholar

Received: 2009-04-22
Accepted: 2009-08-19
Published Online: 2013-04-06
Published in Print: 2009-11-01

© 2009, Carl Hanser Verlag, Munich

Downloaded on 20.2.2024 from
Scroll to top button